what is nuclear energy essay

Nuclear Energy

Nuclear energy is the energy in the nucleus, or core, of an atom. Nuclear energy can be used to create electricity, but it must first be released from the atom.

Engineering, Physics

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Nuclear energy is the energy in the nucleus , or core, of an atom . Atoms are tiny units that make up all matter in the universe , and energy is what holds the nucleus together. There is a huge amount of energy in an atom 's dense nucleus . In fact, the power that holds the nucleus together is officially called the " strong force ." Nuclear energy can be used to create electricity , but it must first be released from the atom . In the process of  nuclear fission , atoms are split to release that energy. A nuclear reactor , or power plant , is a series of machines that can control nuclear fission to produce electricity . The fuel that nuclear reactors use to produce nuclear fission is pellets of the element uranium . In a nuclear reactor , atoms of uranium are forced to break apart. As they split, the atoms release tiny particles called fission products. Fission products cause other uranium atoms to split, starting a chain reaction . The energy released from this chain reaction creates heat. The heat created by nuclear fission warms the reactor's cooling agent . A cooling agent is usually water, but some nuclear reactors use liquid metal or molten salt . The cooling agent , heated by nuclear fission , produces steam . The steam turns turbines , or wheels turned by a flowing current . The turbines drive generators , or engines that create electricity . Rods of material called nuclear poison can adjust how much electricity is produced. Nuclear poisons are materials, such as a type of the element xenon , that absorb some of the fission products created by nuclear fission . The more rods of nuclear poison that are present during the chain reaction , the slower and more controlled the reaction will be. Removing the rods will allow a stronger chain reaction and create more electricity . As of 2011, about 15 percent of the world's electricity is generated by nuclear power plants . The United States has more than 100 reactors, although it creates most of its electricity from fossil fuels and hydroelectric energy . Nations such as Lithuania, France, and Slovakia create almost all of their electricity from nuclear power plants . Nuclear Food: Uranium Uranium is the fuel most widely used to produce nuclear energy . That's because uranium atoms split apart relatively easily. Uranium is also a very common element, found in rocks all over the world. However, the specific type of uranium used to produce nuclear energy , called U-235 , is rare. U-235 makes up less than one percent of the uranium in the world.

Although some of the uranium the United States uses is mined in this country, most is imported . The U.S. gets uranium from Australia, Canada, Kazakhstan, Russia, and Uzbekistan. Once uranium is mined, it must be extracted from other minerals . It must also be processed before it can be used. Because nuclear fuel can be used to create nuclear weapons as well as nuclear reactors , only nations that are part of the Nuclear Non-Proliferation Treaty (NPT) are allowed to import uranium or plutonium , another nuclear fuel . The treaty promotes the peaceful use of nuclear fuel , as well as limiting the spread of nuclear weapons . A typical nuclear reactor uses about 200 tons of uranium every year. Complex processes allow some uranium and plutonium to be re-enriched or recycled . This reduces the amount of mining , extracting , and processing that needs to be done. Nuclear Energy and People Nuclear energy produces electricity that can be used to power homes, schools, businesses, and hospitals. The first nuclear reactor to produce electricity was located near Arco, Idaho. The Experimental Breeder Reactor began powering itself in 1951. The first nuclear power plant designed to provide energy to a community was established in Obninsk, Russia, in 1954. Building nuclear reactors requires a high level of technology , and only the countries that have signed the Nuclear Non-Proliferation Treaty can get the uranium or plutonium that is required. For these reasons, most nuclear power plants are located in the developed world. Nuclear power plants produce renewable, clean energy . They do not pollute the air or release  greenhouse gases . They can be built in urban or rural areas , and do not radically alter the environment around them. The steam powering the turbines and generators is ultimately recycled . It is cooled down in a separate structure called a cooling tower . The steam turns back into water and can be used again to produce more electricity . Excess steam is simply recycled into the atmosphere , where it does little harm as clean water vapor . However, the byproduct of nuclear energy is radioactive material. Radioactive material is a collection of unstable atomic nuclei . These nuclei lose their energy and can affect many materials around them, including organisms and the environment. Radioactive material can be extremely toxic , causing burns and increasing the risk for cancers , blood diseases, and bone decay .

Radioactive waste is what is left over from the operation of a nuclear reactor . Radioactive waste is mostly protective clothing worn by workers, tools, and any other material that have been in contact with radioactive dust. Radioactive waste is long-lasting. Materials like clothes and tools can stay radioactive for thousands of years. The government regulates how these materials are disposed of so they don't contaminate anything else. Used fuel and rods of nuclear poison are extremely radioactive . The used uranium pellets must be stored in special containers that look like large swimming pools. Water cools the fuel and insulates the outside from contact with the radioactivity. Some nuclear plants store their used fuel in dry storage tanks above ground. The storage sites for radioactive waste have become very controversial in the United States. For years, the government planned to construct an enormous nuclear waste facility near Yucca Mountain, Nevada, for instance. Environmental groups and local citizens protested the plan. They worried about radioactive waste leaking into the water supply and the Yucca Mountain environment, about 130 kilometers (80 miles) from the large urban area of Las Vegas, Nevada. Although the government began investigating the site in 1978, it stopped planning for a nuclear waste facility in Yucca Mountain in 2009. Chernobyl Critics of nuclear energy worry that the storage facilities for radioactive waste will leak, crack, or erode . Radioactive material could then contaminate the soil and groundwater near the facility . This could lead to serious health problems for the people and organisms in the area. All communities would have to be evacuated . This is what happened in Chernobyl, Ukraine, in 1986. A steam explosion at one of the power plants four nuclear reactors caused a fire, called a plume . This plume was highly radioactive , creating a cloud of radioactive particles that fell to the ground, called fallout . The fallout spread over the Chernobyl facility , as well as the surrounding area. The fallout drifted with the wind, and the particles entered the water cycle as rain. Radioactivity traced to Chernobyl fell as rain over Scotland and Ireland. Most of the radioactive fallout fell in Belarus.

The environmental impact of the Chernobyl disaster was immediate . For kilometers around the facility , the pine forest dried up and died. The red color of the dead pines earned this area the nickname the Red Forest . Fish from the nearby Pripyat River had so much radioactivity that people could no longer eat them. Cattle and horses in the area died. More than 100,000 people were relocated after the disaster , but the number of human victims of Chernobyl is difficult to determine . The effects of radiation poisoning only appear after many years. Cancers and other diseases can be very difficult to trace to a single source. Future of Nuclear Energy Nuclear reactors use fission, or the splitting of atoms , to produce energy. Nuclear energy can also be produced through fusion, or joining (fusing) atoms together. The sun, for instance, is constantly undergoing nuclear fusion as hydrogen atoms fuse to form helium . Because all life on our planet depends on the sun, you could say that nuclear fusion makes life on Earth possible. Nuclear power plants do not have the capability to safely and reliably produce energy from nuclear fusion . It's not clear whether the process will ever be an option for producing electricity . Nuclear engineers are researching nuclear fusion , however, because the process will likely be safe and cost-effective.

Nuclear Tectonics The decay of uranium deep inside the Earth is responsible for most of the planet's geothermal energy, causing plate tectonics and continental drift.

Three Mile Island The worst nuclear accident in the United States happened at the Three Mile Island facility near Harrisburg, Pennsylvania, in 1979. The cooling system in one of the two reactors malfunctioned, leading to an emission of radioactive fallout. No deaths or injuries were directly linked to the accident.

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• ENVIRONMENT

What is nuclear energy and is it a viable resource?

Nuclear energy's future as an electricity source may depend on scientists' ability to make it cheaper and safer.

Nuclear power is generated by splitting atoms to release the energy held at the core, or nucleus, of those atoms. This process, nuclear fission, generates heat that is directed to a cooling agent—usually water. The resulting steam spins a turbine connected to a generator, producing electricity.

About 450 nuclear reactors provide about 11 percent of the world's electricity. The countries generating the most nuclear power are, in order, the United States, France, China, Russia, and South Korea.

The most common fuel for nuclear power is uranium, an abundant metal found throughout the world. Mined uranium is processed into U-235, an enriched version used as fuel in nuclear reactors because its atoms can be split apart easily.

In a nuclear reactor, neutrons—subatomic particles that have no electric charge—collide with atoms, causing them to split. That collision—called nuclear fission—releases more neutrons that react with more atoms, creating a chain reaction. A byproduct of nuclear reactions, plutonium , can also be used as nuclear fuel.

Types of nuclear reactors

In the U.S. most nuclear reactors are either boiling water reactors , in which the water is heated to the boiling point to release steam, or pressurized water reactors , in which the pressurized water does not boil but funnels heat to a secondary water supply for steam generation. Other types of nuclear power reactors include gas-cooled reactors, which use carbon dioxide as the cooling agent and are used in the U.K., and fast neutron reactors, which are cooled by liquid sodium.

Nuclear energy history

The idea of nuclear power began in the 1930s , when physicist Enrico Fermi first showed that neutrons could split atoms. Fermi led a team that in 1942 achieved the first nuclear chain reaction, under a stadium at the University of Chicago. This was followed by a series of milestones in the 1950s: the first electricity produced from atomic energy at Idaho's Experimental Breeder Reactor I in 1951; the first nuclear power plant in the city of Obninsk in the former Soviet Union in 1954; and the first commercial nuclear power plant in Shippingport, Pennsylvania, in 1957. ( Take our quizzes about nuclear power and see how much you've learned: for Part I, go here ; for Part II, go here .)

Nuclear power, climate change, and future designs

Nuclear power isn't considered renewable energy , given its dependence on a mined, finite resource, but because operating reactors do not emit any of the greenhouse gases that contribute to global warming , proponents say it should be considered a climate change solution . National Geographic emerging explorer Leslie Dewan, for example, wants to resurrect the molten salt reactor , which uses liquid uranium dissolved in molten salt as fuel, arguing it could be safer and less costly than reactors in use today.

Others are working on small modular reactors that could be portable and easier to build. Innovations like those are aimed at saving an industry in crisis as current nuclear plants continue to age and new ones fail to compete on price with natural gas and renewable sources such as wind and solar.

The holy grail for the future of nuclear power involves nuclear fusion, which generates energy when two light nuclei smash together to form a single, heavier nucleus. Fusion could deliver more energy more safely and with far less harmful radioactive waste than fission, but just a small number of people— including a 14-year-old from Arkansas —have managed to build working nuclear fusion reactors. Organizations such as ITER in France and Max Planck Institute of Plasma Physics are working on commercially viable versions, which so far remain elusive.

Nuclear power risks

When arguing against nuclear power, opponents point to the problems of long-lived nuclear waste and the specter of rare but devastating nuclear accidents such as those at Chernobyl in 1986 and Fukushima Daiichi in 2011 . The deadly Chernobyl disaster in Ukraine happened when flawed reactor design and human error caused a power surge and explosion at one of the reactors. Large amounts of radioactivity were released into the air, and hundreds of thousands of people were forced from their homes . Today, the area surrounding the plant—known as the Exclusion Zone—is open to tourists but inhabited only by the various wildlife species, such as gray wolves , that have since taken over .

In the case of Japan's Fukushima Daiichi, the aftermath of the Tohoku earthquake and tsunami caused the plant's catastrophic failures. Several years on, the surrounding towns struggle to recover, evacuees remain afraid to return , and public mistrust has dogged the recovery effort, despite government assurances that most areas are safe.

Other accidents, such as the partial meltdown at Pennsylvania's Three Mile Island in 1979, linger as terrifying examples of nuclear power's radioactive risks. The Fukushima disaster in particular raised questions about safety of power plants in seismic zones, such as Armenia's Metsamor power station.

Other issues related to nuclear power include where and how to store the spent fuel, or nuclear waste, which remains dangerously radioactive for thousands of years. Nuclear power plants, many of which are located on or near coasts because of the proximity to water for cooling, also face rising sea levels and the risk of more extreme storms due to climate change.

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• School Education /

Essay on Nuclear Energy in 500+ words for School Students 

• Updated on  
• Dec 30, 2023

Essay on Nuclear Energy: Nuclear energy has been fascinating and controversial since the beginning. Using atomic power to generate electricity holds the promise of huge energy supplies but we cannot overlook the concerns about safety, environmental impact, and the increase in potential weapon increase. 

The blog will help you to explore various aspects of energy seeking its history, advantages, disadvantages, and role in addressing the global energy challenge. 

Table of Contents

• 1 History Overview
• 2 Nuclear Technology 
• 3 Advantages of Nuclear Energy
• 4 Disadvantages of Nuclear Energy
• 5 Safety Measures and Regulations of Nuclear Energy
• 6 Concerns of Nuclear Proliferation
• 7 Future Prospects and Innovations of Nuclear Energy
• 8 FAQs 

Also Read: Find List of Nuclear Power Plants In India

History Overview

The roots of nuclear energy have their roots back to the early 20th century when innovative discoveries in physics laid the foundation for understanding atomic structure. In the year 1938, Otto Hahn, a German chemist and Fritz Stassman, a German physical chemist discovered nuclear fission, the splitting of atomic nuclei. This discovery opened the way for utilising the immense energy released during the process of fission. 

Also Read: What are the Different Types of Energy?

Nuclear Technology 

Nuclear power plants use controlled fission to produce heat. The heat generated is further used to produce steam, by turning the turbines connected to generators that produce electricity. This process takes place in two types of reactors: Pressurized Water Reactors (PWR) and Boiling Water Reactors (BWR). PWRs use pressurised water to transfer heat. Whereas, BWRs allow water to boil, which produces steam directly. 

Also Read: Nuclear Engineering Course: Universities and Careers

Advantages of Nuclear Energy

Let us learn about the positive aspects of nuclear energy in the following:

1. High Energy Density

Nuclear energy possesses an unparalleled energy density which means that a small amount of nuclear fuel can produce a substantial amount of electricity. This high energy density efficiency makes nuclear power reliable and powerful.

2. Low Greenhouse Gas Emissions

Unlike other traditional fossil fuels, nuclear power generation produces minimum greenhouse gas emissions during electricity generation. The low greenhouse gas emissions feature positions nuclear energy as a potential solution to weakening climate change.

3. Base Load Power

Nuclear power plants provide consistent, baseload power, continuously operating at a stable output level. This makes nuclear energy reliable for meeting the constant demand for electricity, complementing intermittent renewable sources of energy like wind and solar. 

Also Read: How to Become a Nuclear Engineer in India?

Disadvantages of Nuclear Energy

After learning the pros of nuclear energy, now let’s switch to the cons of nuclear energy.

1. Radioactive Waste

One of the most important challenges that is associated with nuclear energy is the management and disposal of radioactive waste. Nuclear power gives rise to spent fuel and other radioactive byproducts that require secure, long-term storage solutions.

2. Nuclear Accidents

The two catastrophic accidents at Chornobyl in 1986 and Fukushima in 2011 underlined the potential risks of nuclear power. These nuclear accidents can lead to severe environmental contamination, human casualties, and long-lasting negative perceptions of the technology. 

3. High Initial Costs

The construction of nuclear power plants includes substantial upfront costs. Moreover, stringent safety measures contribute to the overall expenses, which makes nuclear energy economically challenging compared to some renewable alternatives. 

Also Read: What is the IAEA Full Form?

Safety Measures and Regulations of Nuclear Energy

After recognizing the potential risks associated with nuclear energy, strict safety measures and regulations have been implemented worldwide. These safety measures include reactor design improvements, emergency preparedness, and ongoing monitoring of the plant operations. Regulatory bodies, such as the Nuclear Regulatory Commission (NRC) in the United States, play an important role in overseeing and enforcing safety standards. 

Also Read: What is the Full Form of AEC?

Concerns of Nuclear Proliferation

The dual-use nature of nuclear technology raises concerns about the spread of nuclear weapons. The same nuclear technology used for the peaceful generation of electricity can be diverted for military purposes. International efforts, including the Treaty on the Non-Proliferation of Nuclear Weapons (NPT), aim to help the proliferation of nuclear weapons and promote the peaceful use of nuclear energy. 

Also Read: Dr. Homi J. Bhabha’s Education, Inventions & Discoveries

Future Prospects and Innovations of Nuclear Energy

The ongoing research and development into advanced reactor technologies are part of nuclear energy. Concepts like small modular reactors (SMRs) and Generation IV reactors aim to address safety, efficiency, and waste management concerns. Moreover, the exploration of nuclear fusion as a clean and virtually limitless energy source represents an innovation for future energy solutions. 

Nuclear energy stands at the crossroads of possibility and peril, offering the possibility of addressing the world´s growing energy needs while posing important challenges. Striking a balance between utilising the benefits of nuclear power and alleviating its risks requires ongoing technological innovation, powerful safety measures, and international cooperation. 

As we drive the complexities of perspective challenges of nuclear energy, the role of nuclear energy in the global energy mix remains a subject of ongoing debate and exploration. 

Also Read: Essay on Science and Technology for Students: 100, 200, 350 Words

Ans. Nuclear energy is the energy released during nuclear reactions. Its importance lies in generating electricity, medical applications, and powering spacecraft.

Ans. Nuclear energy is exploited from the nucleus of atoms through processes like fission or fusion. It is a powerful and controversial energy source with applications in power generation and various technologies. 

Ans. The five benefits of nuclear energy include: 1. Less greenhouse gas emissions 2. High energy density 3. Continuos power generation  4. Relatively low fuel consumption 5. Potential for reducing dependence on fossil fuels

Ans. Three important facts about nuclear energy: a. Nuclear fission releases a significant amount of energy. b. Nuclear power plants use controlled fission reactions to generate electricity. c. Nuclear fusion, combining atomic nuclei, is a potential future energy source.

Ans. Nuclear energy is considered best due to its low carbon footprint, high energy output, and potential to address energy needs. However, concerns about safety, radioactive waste, and proliferation risk are challenges that need careful consideration.

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Deepika Joshi

Deepika Joshi is an experienced content writer with expertise in creating educational and informative content. She has a year of experience writing content for speeches, essays, NCERT, study abroad and EdTech SaaS. Her strengths lie in conducting thorough research and ananlysis to provide accurate and up-to-date information to readers. She enjoys staying updated on new skills and knowledge, particulary in education domain. In her free time, she loves to read articles, and blogs with related to her field to further expand her expertise. In personal life, she loves creative writing and aspire to connect with innovative people who have fresh ideas to offer.

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The Advantages and Disadvantages of Nuclear Energy

Since the first nuclear plant started operations in the 1950s, the world has been highly divided on nuclear as a source of energy. While it is a cleaner alternative to fossil fuels, this type of power is also associated with some of the world’s most dangerous and deadliest weapons, not to mention nuclear disasters . The extremely high cost and lengthy process to build nuclear plants are compensated by the fact that producing nuclear energy is not nearly as polluting as oil and coal. In the race to net-zero carbon emissions, should countries still rely on nuclear energy or should they make space for more fossil fuels and renewable energy sources? We take a look at the advantages and disadvantages of nuclear energy. 

What Is Nuclear Energy?

Nuclear energy is the energy source found in an atom’s nucleus, or core. Once extracted, this energy can be used to produce electricity by creating nuclear fission in a reactor through two kinds of atomic reaction: nuclear fusion and nuclear fission. During the latter, uranium used as fuel causes atoms to split into two or more nuclei. The energy released from fission generates heat that brings a cooling agent, usually water, to boil. The steam deriving from boiling or pressurised water is then channelled to spin turbines to generate electricity. To produce nuclear fission, reactors make use of uranium as fuel.

For centuries, the industrialisation of economies around the world was made possible by fossil fuels like coal, natural gas, and petroleum and only in recent years countries opened up to alternative, renewable sources like solar and wind energy. In the 1950s, early commercial nuclear power stations started operations, offering to many countries around the world an alternative to oil and gas import dependency and a far less polluting energy source than fossil fuels. Following the 1970s energy crisis and the dramatic increase of oil prices that resulted from it, more and more countries decided to embark on nuclear power programmes. Indeed, most reactors have been built  between 1970 and 1985 worldwide. Today, nuclear energy meets around 10% of global energy demand , with 439 currently operational nuclear plants in 32 countries and about 55 new reactors under construction. In 2020, 13 countries produced at least one-quarter of their total electricity from nuclear, with the US, China, and France dominating the market by far. 

Fossil fuels make up 60% of the United States’ electricity while the remaining 40% is equally split between renewables and nuclear power. France embarked on a sweeping expansion of its nuclear power industry in the 1970s with the ultimate goal of breaking its dependence on foreign oil. In doing this, the country was able to build up its economy by simultaneously cutting its emissions at a rate never seen before. Today, France is home to 56 operating reactors and it relies on nuclear power for 70% of its electricity . 

You might also like: A ‘Breakthrough’ In Nuclear Fusion: What Does It Mean for the Future of Energy Generation?

Advantages of Nuclear Energy

France’s success in cutting down emissions is a clear example of some of the main advantages of nuclear energy over fossil fuels. First and foremost, nuclear energy is clean and it provides pollution-free power with no greenhouse gas emissions. Contrary to what many believe, cooling towers in nuclear plants only emit water vapour and are thus, not releasing any pollutant or radioactive substance into the atmosphere. Compared to all the energy alternatives we currently have on hand, many experts believe that nuclear energy is indeed one of the cleanest sources. Many nuclear energy supporters also argue that nuclear power is responsible for the fastest decarbonisation effort in history , with big nuclear players like France, Saudi Arabia, Canada, and South Korea being among the countries that recorded the fastest decline in carbon intensity and experienced a clean energy transition by building nuclear reactors and hydroelectric dams.

Earlier this year, the European Commission took a clear stance on nuclear power by labelling it a green source of energy in its classification system establishing a list of environmentally sustainable economic activities. While nuclear energy may be clean and its production emission-free, experts highlight a hidden danger of this power: nuclear waste. The highly radioactive and toxic byproduct from nuclear reactors can remain radioactive for tens of thousands of years. However, this is still considered a much easier environmental problem to solve than climate change. The main reason for this is that as much as 90% of the nuclear waste generated by the production of nuclear energy can be recycled. Indeed, the fuel used in a reactor, typically uranium, can be treated and put into another reactor as only a small amount of energy in their fuel is extracted in the fission process.

A rather important advantage of nuclear energy is that it is much safer than fossil fuels from a public health perspective. The pro-nuclear movement leverages the fact that nuclear waste is not even remotely as dangerous as the toxic chemicals coming from fossil fuels. Indeed, coal and oil act as ‘ invisible killers ’ and are responsible for 1 in 5 deaths worldwide . In 2018 alone, fossil fuels killed 8.7 million people globally. In contrast, in nearly 70 years since the beginning of nuclear power, only three accidents have raised public alarm: the 1979 Three Mile Island accident, the 1986 Chernobyl disaster and the 2011 Fukushima nuclear disaster. Of these, only the accident at the Chernobyl nuclear plant in Ukraine directly caused any deaths.

Finally, nuclear energy has some advantages compared to some of the most popular renewable energy sources. According to the US Office of Nuclear Energy , nuclear power has by far the highest capacity factor, with plants requiring less maintenance, capable to operate for up to two years before refuelling and able to produce maximum power more than 93% of the time during the year, making them three times more reliable than wind and solar plants. 

You might also like: Nuclear Energy: A Silver Bullet For Clean Energy?

Disadvantages of Nuclear Energy

The anti-nuclear movement opposes the use of this type of energy for several reasons. The first and currently most talked about disadvantage of nuclear energy is the nuclear weapon proliferation, a debate triggered by the deadly atomic bombing of the Japanese cities of Hiroshima and Nagasaki during the Second World War and recently reopened following rising concerns over nuclear escalation in the Ukraine-Russia conflict . After the world saw the highly destructive effect of these bombs, which caused the death of tens of thousands of people, not only in the impact itself but also in the days, weeks, and months after the tragedy as a consequence of radiation sickness, nuclear energy evolved to a pure means of generating electricity. In 1970, the Treaty on the Non-Proliferation of Nuclear Weapons entered into force. Its objective was to prevent the spread of such weapons to eventually achieve nuclear disarmament as well as promote peaceful uses of nuclear energy. However, opposers of this energy source still see nuclear energy as being deeply intertwined with nuclear weapons technologies and believe that, with nuclear technologies becoming globally available, the risk of them falling into the wrong hands is high, especially in countries with high levels of corruption and instability. 

As mentioned in the previous section, nuclear energy is clean. However, radioactive nuclear waste contains highly poisonous chemicals like plutonium and the uranium pellets used as fuel. These materials can be extremely toxic for tens of thousands of years and for this reason, they need to be meticulously and permanently disposed of. Since the 1950s, a stockpile of 250,000 tonnes of highly radioactive nuclear waste has been accumulated and distributed across the world, with 90,000 metric tons stored in the US alone. Knowing the dangers of nuclear waste, many oppose nuclear energy for fears of accidents, despite these being extremely unlikely to happen. Indeed, opposers know that when nuclear does fail, it can fail spectacularly. They were reminded of this in 2011, when the Fukushima disaster, despite not killing anyone directly, led to the displacement of more than 150,000 people, thousands of evacuation/related deaths and billions of dollars in cleanup costs. 

Lastly, if compared to other sources of energy, nuclear power is one of the most expensive and time-consuming forms of energy. Nuclear plants cost billions of dollars to build and they take much longer than any other infrastructure for renewable energy, sometimes even more than a decade. However, while nuclear power plants are expensive to build, they are relatively cheap to run , a factor that improves its competitiveness. Still, the long building process is considered a significant obstacle in the run to net-zero emissions that countries around the world have committed to. If they hope to meet their emission reduction targets in time, they cannot afford to rely on new nuclear plants.

You might also like: The Nuclear Waste Disposal Dilemma

Who Wins the Nuclear Debate?

There are a multitude of advantages and disadvantages of nuclear energy and the debate on whether to keep this technology or find other alternatives is destined to continue in the years to come. Nuclear power can be a highly destructive weapon, but the risks of a nuclear catastrophe are relatively low. While historic nuclear disasters can be counted on the fingers of a single hand, they are remembered for their devastating impact and the life-threatening consequences they sparked (or almost sparked). However, it is important to remember that fossil fuels like coal and oil represent a much bigger threat and silently kill millions of people every year worldwide. Another big aspect to take into account, and one that is currently discussed by global leaders, is the dependence of some of the world’s largest economies on countries like Russia, Saudi Arabia, and Iraq for fossil fuels. While the 2011 Fukushima disaster, for example, pushed the then-German Chancellor Angela Merkel to close all of Germany’s nuclear plants, her decision only increased the country’s dependence on much more polluting Russian oil. Nuclear supporters argue that relying on nuclear energy would decrease the energy dependency from third countries. However, raw materials such as the uranium needed to make plants function would still need to be imported from countries like Canada, Kazakhstan, and Australia. The debate thus shifts to another problem: which countries should we rely on for imports and, most importantly, is it worth keeping these dependencies?

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Introduction to Nuclear Energy

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Fast Facts About Nuclear Energy

Principal Energy Use: Electricity

Nuclear energy is a carbon-free and extremely energy dense resource that produces no air pollution . Nuclear reactions produce large amounts of energy in the form of heat. That heat can be used to power a steam turbine and generate electricity. There are two types of nuclear reactions:

• Nuclear fission occurs when a large atom is split into smaller atoms, producing lots of heat and long-lived radioactive waste . See our Nuclear Fission page for more information.
• Nuclear fusion occurs when two nuclei combine to form a single nucleus, releasing massive amounts of heat with no long-lived radioactive waste (the sun is a nuclear fusion reactor). See our Nuclear Fusion page for more information.

All commercial nuclear power plants today use nuclear fission. The highly radioactive byproducts of nuclear fission must be secured away from people for hundreds of thousands of years, but we have no proven long term solutions for doing that. Nuclear fusion is still in the research phase.

Both nuclear fission and nuclear fusion have benefited from large amounts of government funding for basic science, technology, fuel-sourcing, and regulation; and both forms have origins in the defense industry (nuclear bombs - fission; hydrogen bombs - fission and fusion).

Fission and Fusion Characteristics

Climate impact: low.

• Near-zero emissions (fission and fusion)

Environmental Impact: Low to Medium

• No air pollution (fission and fusion)
• Radioactive waste is toxic for hundreds of thousands of years
• Risk of radiation leaks from nuclear meltdowns
• Large amounts of water used for cooling; thermal pollution of water
• Mining of uranium can pollute water and degrade land and habitat
• Nuclear waste can be used for bombs; high security required to reduce the risk of proliferation
• No long-lived radioactive waste

Updated October 2023

Our Lecture on Introduction to Nuclear Energy

This is our Stanford University Understand Energy course introduction to nuclear energy. We encourage you to watch this 5-minute video for important context before diving into the more in-depth content on our Nuclear Fission and Nuclear Fusion pages.

Presented by: Diana Gragg, PhD ; Core Lecturer, Civil and Environmental Engineering, Stanford University; Explore Energy Managing Director, Precourt Institute for Energy Recorded on: September 13, 2023    Duration:  5 minutes

Lecture slides available upon request .

Next Topic: Nuclear Fission Other Energy Topics to Explore

Fast Facts Sources Overview: Breeze, P. Power generation technologies, 3 rd . edition. Newnes, 2019; What is Nuclear Energy? The Science of Nuclear Power . IAEA, 2022; Nuclear Explained . EIA, 2022; Nuclear Fusion Power . WNA, 2022. Chart of Characteristics: Fission vs Fusion: What's the Difference? DOE, 2019; Nuclear Power for Electrical Generation . NRC; Nuclear Explained . EIA, 2022; Nuclear Power in the World Today. WNA, 2023; Fusion Device Information System . n.d. More details available on request . Back to Fast Facts

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Nuclear Power in a Clean Energy System

About this report.

With nuclear power facing an uncertain future in many countries, the world risks a steep decline in its use in advanced economies that could result in billions of tonnes of additional carbon emissions. Some countries have opted out of nuclear power in light of concerns about safety and other issues. Many others, however, still see a role for nuclear in their energy transitions but are not doing enough to meet their goals.

The publication of the IEA's first report addressing nuclear power in nearly two decades brings this important topic back into the global energy debate.

Key findings

Nuclear power is the second-largest source of low-carbon electricity today.

Nuclear power is the second-largest source of low-carbon electricity today, with 452 operating reactors providing 2700 TWh of electricity in 2018, or 10% of global electricity supply.

In advanced economies, nuclear has long been the largest source of low-carbon electricity, providing 18% of supply in 2018. Yet nuclear is quickly losing ground. While 11.2 GW of new nuclear capacity was connected to power grids globally in 2018 – the highest total since 1990 – these additions were concentrated in China and Russia.

Global low-carbon power generation by source, 2018

Cumulative co2 emissions avoided by global nuclear power in selected countries, 1971-2018, an aging nuclear fleet.

In the absense of further lifetime extensions and new projects could result in an additional 4 billion tonnes of CO2 emissions, underlining the importance of the nuclear fleet to low-carbon energy transitions around the globe. In emerging and developing economies, particularly China, the nuclear fleet will provide low-carbon electricity for decades to come.

However the nuclear fleet in advanced economies is 35 years old on average and many plants are nearing the end of their designed lifetimes. Given their age, plants are beginning to close, with 25% of existing nuclear capacity in advanced economies expected to be shut down by 2025.

It is considerably cheaper to extend the life of a reactor than build a new plant, and costs of extensions are competitive with other clean energy options, including new solar PV and wind projects. Nevertheless they still represent a substantial capital investment. The estimated cost of extending the operational life of 1 GW of nuclear capacity for at least 10 years ranges from $500 million to just over $1 billion depending on the condition of the site.

However difficult market conditions are a barrier to lifetime extension investments. An extended period of low wholesale electricity prices in most advanced economies has sharply reduced or eliminated margins for many technologies, putting nuclear at risk of shutting down early if additional investments are needed. As such, the feasibility of extensions depends largely on domestic market conditions.

Age profile of nuclear power capacity in selected regions, 2019

United states, levelised cost of electricity in the united states, 2040, european union, levelised cost of electricity in the european union, 2040, levelised cost of electricity in japan, 2040, the nuclear fade case, nuclear capacity operating in selected advanced economies in the nuclear fade case, 2018-2040, wind and solar pv generation by scenario 2019-2040, policy recommendations.

In this context, countries that intend to retain the option of nuclear power should consider the following actions:

• Keep the option open:  Authorise lifetime extensions of existing nuclear plants for as long as safely possible. 
• Value dispatchability:  Design the electricity market in a way that properly values the system services needed to maintain electricity security, including capacity availability and frequency control services. Make sure that the providers of these services, including nuclear power plants, are compensated in a competitive and non-discriminatory manner.
• Value non-market benefits:  Establish a level playing field for nuclear power with other low-carbon energy sources in recognition of its environmental and energy security benefits and remunerate it accordingly.
• Update safety regulations:  Where necessary, update safety regulations in order to ensure the continued safe operation of nuclear plants. Where technically possible, this should include allowing flexible operation of nuclear power plants to supply ancillary services.
• Create a favourable financing framework:  Create risk management and financing frameworks that facilitate the mobilisation of capital for new and existing plants at an acceptable cost taking the risk profile and long time-horizons of nuclear projects into consideration.
• Support new construction:  Ensure that licensing processes do not lead to project delays and cost increases that are not justified by safety requirements.
• Support innovative new reactor designs:  Accelerate innovation in new reactor designs with lower capital costs and shorter lead times and technologies that improve the operating flexibility of nuclear power plants to facilitate the integration of growing wind and solar capacity into the electricity system.
• Maintain human capital:  Protect and develop the human capital and project management capabilities in nuclear engineering.

Executive summary

Nuclear power can play an important role in clean energy transitions.

Nuclear power today makes a significant contribution to electricity generation, providing 10% of global electricity supply in 2018.  In advanced economies 1 , nuclear power accounts for 18% of generation and is the largest low-carbon source of electricity. However, its share of global electricity supply has been declining in recent years. That has been driven by advanced economies, where nuclear fleets are ageing, additions of new capacity have dwindled to a trickle, and some plants built in the 1970s and 1980s have been retired. This has slowed the transition towards a clean electricity system. Despite the impressive growth of solar and wind power, the overall share of clean energy sources in total electricity supply in 2018, at 36%, was the same as it was 20 years earlier because of the decline in nuclear. Halting that slide will be vital to stepping up the pace of the decarbonisation of electricity supply.

A range of technologies, including nuclear power, will be needed for clean energy transitions around the world.  Global energy is increasingly based around electricity. That means the key to making energy systems clean is to turn the electricity sector from the largest producer of CO 2 emissions into a low-carbon source that reduces fossil fuel emissions in areas like transport, heating and industry. While renewables are expected to continue to lead, nuclear power can also play an important part along with fossil fuels using carbon capture, utilisation and storage. Countries envisaging a future role for nuclear account for the bulk of global energy demand and CO 2 emissions. But to achieve a trajectory consistent with sustainability targets – including international climate goals – the expansion of clean electricity would need to be three times faster than at present. It would require 85% of global electricity to come from clean sources by 2040, compared with just 36% today. Along with massive investments in efficiency and renewables, the trajectory would need an 80% increase in global nuclear power production by 2040.

Nuclear power plants contribute to electricity security in multiple ways.  Nuclear plants help to keep power grids stable. To a certain extent, they can adjust their operations to follow demand and supply shifts. As the share of variable renewables like wind and solar photovoltaics (PV) rises, the need for such services will increase. Nuclear plants can help to limit the impacts from seasonal fluctuations in output from renewables and bolster energy security by reducing dependence on imported fuels.

Lifetime extensions of nuclear power plants are crucial to getting the energy transition back on track

Policy and regulatory decisions remain critical to the fate of ageing reactors in advanced economies.  The average age of their nuclear fleets is 35 years. The European Union and the United States have the largest active nuclear fleets (over 100 gigawatts each), and they are also among the oldest: the average reactor is 35 years old in the European Union and 39 years old in the United States. The original design lifetime for operations was 40 years in most cases. Around one quarter of the current nuclear capacity in advanced economies is set to be shut down by 2025 – mainly because of policies to reduce nuclear’s role. The fate of the remaining capacity depends on decisions about lifetime extensions in the coming years. In the United States, for example, some 90 reactors have 60-year operating licenses, yet several have already been retired early and many more are at risk. In Europe, Japan and other advanced economies, extensions of plants’ lifetimes also face uncertain prospects.

Economic factors are also at play.  Lifetime extensions are considerably cheaper than new construction and are generally cost-competitive with other electricity generation technologies, including new wind and solar projects. However, they still need significant investment to replace and refurbish key components that enable plants to continue operating safely. Low wholesale electricity and carbon prices, together with new regulations on the use of water for cooling reactors, are making some plants in the United States financially unviable. In addition, markets and regulatory systems often penalise nuclear power by not pricing in its value as a clean energy source and its contribution to electricity security. As a result, most nuclear power plants in advanced economies are at risk of closing prematurely.

The hurdles to investment in new nuclear projects in advanced economies are daunting

What happens with plans to build new nuclear plants will significantly affect the chances of achieving clean energy transitions.  Preventing premature decommissioning and enabling longer extensions would reduce the need to ramp up renewables. But without new construction, nuclear power can only provide temporary support for the shift to cleaner energy systems. The biggest barrier to new nuclear construction is mobilising investment.  Plans to build new nuclear plants face concerns about competitiveness with other power generation technologies and the very large size of nuclear projects that require billions of dollars in upfront investment. Those doubts are especially strong in countries that have introduced competitive wholesale markets.

A number of challenges specific to the nature of nuclear power technology may prevent investment from going ahead.  The main obstacles relate to the sheer scale of investment and long lead times; the risk of construction problems, delays and cost overruns; and the possibility of future changes in policy or the electricity system itself. There have been long delays in completing advanced reactors that are still being built in Finland, France and the United States. They have turned out to cost far more than originally expected and dampened investor interest in new projects. For example, Korea has a much better record of completing construction of new projects on time and on budget, although the country plans to reduce its reliance on nuclear power.

Without nuclear investment, achieving a sustainable energy system will be much harder

A collapse in investment in existing and new nuclear plants in advanced economies would have implications for emissions, costs and energy security.  In the case where no further investments are made in advanced economies to extend the operating lifetime of existing nuclear power plants or to develop new projects, nuclear power capacity in those countries would decline by around two-thirds by 2040. Under the current policy ambitions of governments, while renewable investment would continue to grow, gas and, to a lesser extent, coal would play significant roles in replacing nuclear. This would further increase the importance of gas for countries’ electricity security. Cumulative CO 2 emissions would rise by 4 billion tonnes by 2040, adding to the already considerable difficulties of reaching emissions targets. Investment needs would increase by almost USD 340 billion as new power generation capacity and supporting grid infrastructure is built to offset retiring nuclear plants.

Achieving the clean energy transition with less nuclear power is possible but would require an extraordinary effort.  Policy makers and regulators would have to find ways to create the conditions to spur the necessary investment in other clean energy technologies. Advanced economies would face a sizeable shortfall of low-carbon electricity. Wind and solar PV would be the main sources called upon to replace nuclear, and their pace of growth would need to accelerate at an unprecedented rate. Over the past 20 years, wind and solar PV capacity has increased by about 580 GW in advanced economies. But in the next 20 years, nearly five times that much would need to be built to offset nuclear’s decline. For wind and solar PV to achieve that growth, various non-market barriers would need to be overcome such as public and social acceptance of the projects themselves and the associated expansion in network infrastructure. Nuclear power, meanwhile, can contribute to easing the technical difficulties of integrating renewables and lowering the cost of transforming the electricity system.

With nuclear power fading away, electricity systems become less flexible.  Options to offset this include new gas-fired power plants, increased storage (such as pumped storage, batteries or chemical technologies like hydrogen) and demand-side actions (in which consumers are encouraged to shift or lower their consumption in real time in response to price signals). Increasing interconnection with neighbouring systems would also provide additional flexibility, but its effectiveness diminishes when all systems in a region have very high shares of wind and solar PV.

Offsetting less nuclear power with more renewables would cost more

Taking nuclear out of the equation results in higher electricity prices for consumers.  A sharp decline in nuclear in advanced economies would mean a substantial increase in investment needs for other forms of power generation and the electricity network. Around USD 1.6 trillion in additional investment would be required in the electricity sector in advanced economies from 2018 to 2040. Despite recent declines in wind and solar costs, adding new renewable capacity requires considerably more capital investment than extending the lifetimes of existing nuclear reactors. The need to extend the transmission grid to connect new plants and upgrade existing lines to handle the extra power output also increases costs. The additional investment required in advanced economies would not be offset by savings in operational costs, as fuel costs for nuclear power are low, and operation and maintenance make up a minor portion of total electricity supply costs. Without widespread lifetime extensions or new projects, electricity supply costs would be close to USD 80 billion higher per year on average for advanced economies as a whole.

Strong policy support is needed to secure investment in existing and new nuclear plants

Countries that have kept the option of using nuclear power need to reform their policies to ensure competition on a level playing field.  They also need to address barriers to investment in lifetime extensions and new capacity. The focus should be on designing electricity markets in a way that values the clean energy and energy security attributes of low-carbon technologies, including nuclear power.

Securing investment in new nuclear plants would require more intrusive policy intervention given the very high cost of projects and unfavourable recent experiences in some countries.  Investment policies need to overcome financing barriers through a combination of long-term contracts, price guarantees and direct state investment.

Interest is rising in advanced nuclear technologies that suit private investment such as small modular reactors (SMRs).  This technology is still at the development stage. There is a case for governments to promote it through funding for research and development, public-private partnerships for venture capital and early deployment grants. Standardisation of reactor designs would be crucial to benefit from economies of scale in the manufacturing of SMRs.

Continued activity in the operation and development of nuclear technology is required to maintain skills and expertise.  The relatively slow pace of nuclear deployment in advanced economies in recent years means there is a risk of losing human capital and technical know-how. Maintaining human skills and industrial expertise should be a priority for countries that aim to continue relying on nuclear power.

The following recommendations are directed at countries that intend to retain the option of nuclear power. The IEA makes no recommendations to countries that have chosen not to use nuclear power in their clean energy transition and respects their choice to do so.

• Keep the option open:  Authorise lifetime extensions of existing nuclear plants for as long as safely possible.
• Value non-market benefits:  Establish a level playing field for nuclear power with other low carbon energy sources in recognition of its environmental and energy security benefits and remunerate it accordingly.
• Create an attractive financing framework:  Set up risk management and financing frameworks that can help mobilise capital for new and existing plants at an acceptable cost, taking the risk profile and long time horizons of nuclear projects into consideration.
• Support new construction:  Ensure that licensing processes do not lead to project delays and cost increases that are not justified by safety requirements. Support standardisation and enable learning-by-doing across the industry.
• Support innovative new reactor designs:  Accelerate innovation in new reactor designs, such as small modular reactors (SMRs), with lower capital costs and shorter lead times and technologies that improve the operating flexibility of nuclear power plants to facilitate the integration of growing wind and solar capacity into the electricity system.

Advanced economies consist of Australia, Canada, Chile, the 28 members of the European Union, Iceland, Israel, Japan, Korea, Mexico, New Zealand, Norway, Switzerland, Turkey and the United States.

Reference 1

Cite report.

IEA (2019), Nuclear Power in a Clean Energy System , IEA, Paris https://www.iea.org/reports/nuclear-power-in-a-clean-energy-system, Licence: CC BY 4.0

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Back to the Future Josh Freed

Leslie and mark's old/new idea.

The Nuclear Science and Engineering Library at MIT is not a place where most people would go to unwind. It’s filled with journals that have articles with titles like “Longitudinal double-spin asymmetry of electrons from heavy flavor decays in polarized p + p collisions at √s = 200 GeV.” But nuclear engineering Ph.D. candidates relax in ways all their own. In the winter of 2009, two of those candidates, Leslie Dewan and Mark Massie, were studying for their qualifying exams—a brutal rite of passage—and had a serious need to decompress.

To clear their heads after long days and nights of reviewing neutron transport, the mathematics behind thermohydraulics, and other such subjects, they browsed through the crinkled pages of journals from the first days of their industry—the glory days. Reading articles by scientists working in the 1950s and ‘60s, they found themselves marveling at the sense of infinite possibility those pioneers had brought to their work, in awe of the huge outpouring of creative energy. They were also curious about the dozens of different reactor technologies that had once been explored, only to be abandoned when the funding dried up.

The early nuclear researchers were all housed in government laboratories—at Oak Ridge in Tennessee, at the Idaho National Lab in the high desert of eastern Idaho, at Argonne in Chicago, and Los Alamos in New Mexico. Across the country, the nation’s top physicists, metallurgists, mathematicians, and engineers worked together in an atmosphere of feverish excitement, as government support gave them the freedom to explore the furthest boundaries of their burgeoning new field. Locked in what they thought of as a life-or-death race with the Soviet Union, they aimed to be first in every aspect of scientific inquiry, especially those that involved atom splitting.

1955: Argonne's BORAX III reactor provided all the electricity for Arco, Idaho, the first time any community's electricity was provided entirely by nuclear energy. Source: Wikimedia Commons

Though nuclear engineers were mostly men in those days, Leslie imagined herself working alongside them, wearing a white lab coat, thinking big thoughts. “It was all so fresh, so exciting, so limitless back then,” she told me. “They were designing all sorts of things: nuclear-powered cars and airplanes, reactors cooled by lead. Today, it’s much less interesting. Most of us are just working on ways to tweak basically the same light water reactor we’ve been building for 50 years.”

1958: The Ford Nucleon scale-model concept car developed by Ford Motor Company as a design of how a nuclear-powered car might look. Source: Wikimedia Commons

But because of something that she and Mark stumbled across in the library during one of their forays into the old journals, Leslie herself is not doing that kind of tweaking—she’s trying to do something much more radical. One night, Mark showed Leslie a 50-year-old paper from Oak Ridge about a reactor powered not by rods of metal-clad uranium pellets in water, like the light water reactors of today, but by a liquid fuel of uranium mixed into molten salt to keep it at a constant temperature. The two were intrigued, because it was clear from the paper that the molten salt design could potentially be constructed at a lower cost and shut down more easily in an emergency than today’s light water reactors. And the molten salt design wasn’t just theoretical—Oak Ridge had built a real reactor, which ran from 1965-1969, racking up 20,000 operating hours.

The 1960s-era salt reactor was interesting, but at first blush it didn’t seem practical enough to revive. It was bulky, expensive, and not very efficient. Worse, it ran on uranium enriched to levels far above the modern legal limit for commercial nuclear power. Most modern light water reactors run on 5 percent enriched uranium, and it is illegal under international and domestic law for commercial power generators to use anything above 20 percent, because at levels that high uranium can be used for making weapons. The Oak Ridge molten salt reactor needed uranium enriched to at least 33 percent, possibly even higher.

Aircraft Reactor Experiment building at ORNL (Extensive research into molten salt reactors started with the U.S. aircraft reactor experiment (ARE) in support of the U.S. Aircraft Nuclear Propulsion program.) Wikimedia Commons

1964: Molten salt reactor at Oak Ridge. Source: Wikimedia Commons

But they were aware that smart young engineers were considering applying modern technology to several other decades-old reactor designs from the dawn of the nuclear age, and this one seemed to Leslie and Mark to warrant a second look. After finishing their exams, they started searching for new materials that could be used in a molten salt reactor to make it both legal and more efficient. If they could show that a modified version of the old design could compete with—or exceed—the performance of today’s light water reactors, they knew they might have a very interesting project on their hands.

First, they took a look at the fuel. By using different, more modern materials, they had a theory that they could get the reactor to work at very low enrichment levels. Maybe, they hoped, even significantly below 5 percent.

There was a good reason to hope. Today’s reactors produce a significant amount of nuclear “waste,” many tons of which are currently sitting in cooling pools and storage canisters at plant sites all over the country. The reason that the waste has to be managed so carefully is that when they are discarded, the uranium fuel rods contain about 95 percent of the original amount of energy and remain both highly radioactive and hot enough to boil water. It dawned on Leslie and Mark that if they could chop up the rods and remove their metal cladding, they might have a “killer app”—a sector-redefining technology like Uber or Airbnb—for their molten salt reactor design, enabling it to run on the waste itself.

By late 2010, the computer modeling they were doing suggested this might indeed work. When Leslie left for a trip to Egypt with her family in January 2011, Mark kept running simulations back at MIT. On January 11, he sent his partner an email that she read as she toured the sites of Alexandria. The note was highly technical, but said in essence that Mark’s latest work confirmed their hunch—they could indeed make their reactor run on nuclear waste. Leslie looked up from her phone and said to her brother: “I need to go back to Boston.”

Watch Leslie Dewan and Mark Massie on the future of nuclear energy

Climate Change Spurs New Call for Nuclear Energy

In the days when Leslie and Mark were studying for their exams, it may have seemed that the Golden Age of nuclear energy in the United States had long since passed. Not a single new commercial reactor project had been built here in over 30 years. Not only were there no new reactors, but with the fracking boom having produced abundant supplies of cheap natural gas, some electric utilities were shutting down their aging reactors rather than doing the costly upgrades needed to keep them online.

As the domestic reactor market went into decline, the American supply chain for nuclear reactor parts withered. Although almost all commercial nuclear technology had been discovered in the United States, our competitors eventually purchased much of our nuclear industrial base, with Toshiba buying Westinghouse, for example.* Not surprisingly, as the nuclear pioneers aged and young scientists stayed away from what seemed to be a dying industry, the number of nuclear engineers also dwindled over the decades. In addition, the American regulatory system, long considered the gold standard for western nuclear systems, began to lose influence as other countries pressed ahead with new reactor construction while the U.S. market remained dormant.

Yet something has changed in recent years. Leslie and Mark are not really outliers. All of a sudden, a flood of young engineers has entered the field. More than 1,164 nuclear engineering degrees were awarded in 2013—a 160 percent increase over the number granted a decade ago.

So what, after a 30-year drought, is drawing smart young people back to the nuclear industry? The answer is climate change. Nuclear energy currently provides about 20 percent of the electric power in the United States, and it does so without emitting any greenhouse gases. Compare that to the amount of electricity produced by the other main non-emitting sources of power, the so-called “renewables”—hydroelectric (6.8 percent), wind (4.2 percent) and solar (about one quarter of a percent). Not only are nuclear plants the most important of the non-emitting sources, but they provide baseload—“always there”—power, while most renewables can produce electricity only intermittently, when the wind is blowing or the sun is shining.

In 2014, the Intergovernmental Panel on Climate Change, a United Nations-based organization that is the leading international body for the assessment of climate risk, issued a desperate call for more non-emitting power sources. According to the IPCC, in order to mitigate climate change and meet growing energy demands, the world must aggressively expand its sources of renewable energy, and it must also build more than 400 new nuclear reactors in the next 20 years—a near-doubling of today’s global fleet of 435 reactors. However, in the wake of the tsunami that struck Japan’s Fukushima Daichi plant in 2011, some countries are newly fearful about the safety of light water reactors. Germany, for example, vowed to shutter its entire nuclear fleet.

November 6, 2013: The spent fuel pool inside the No.4 reactor building at the tsunami-crippled Tokyo Electric Power Co.'s (TEPCO) Fukushima Daiichi nuclear power plant. Source: REUTERS/Kyodo (Japan)

The young scientists entering the nuclear energy field know all of this. They understand that a major build-out of nuclear reactors could play a vital role in saving the world from climate disaster. But they also recognize that for that to happen, there must be significant changes in the technology of the reactors, because fear of light water reactors means that the world is not going to be willing to fund and build enough of them to supply the necessary energy. That’s what had sent Leslie and Mark into the library stacks at MIT—a search for new ideas that might be buried in the old designs.

They have now launched a company, Transatomic, to build the molten salt reactor they see as a viable answer to the problem. And they’re not alone—at least eight other startups have emerged in recent years, each with its own advanced reactor design. This new generation of pioneers is working with the same sense of mission and urgency that animated the discipline’s founders. The existential threat that drove the men of Oak Ridge and Argonne was posed by the Soviets; the threat of today is from climate change.

Heeding that sense of urgency, investors from Silicon Valley and elsewhere are stepping up to provide funding. One startup, TerraPower, has the backing of Microsoft co-founder Bill Gates and former Microsoft executive Nathan Myhrvold. Another, General Fusion, has raised $32 million from investors, including nearly $20 million from Amazon founder Jeff Bezos. And LPP Fusion has even benefited, to the tune of $180,000, from an Indiegogo crowd-funding campaign.

All of the new blood, new ideas, and new money are having a real effect. In the last several years, a field that had been moribund has become dynamic again, once more charged with a feeling of boundless possibility and optimism.

But one huge source of funding and support enjoyed by those first pioneers has all but disappeared: The U.S. government.

The "Atoms for Peace" program supplied equipment and information to schools, hospitals, and research institutions within the U.S. and throughout the world. Source: Wikipedia

From Atoms for Peace to Chernobyl

December 8, 1953: U.S. President Eisenhower delivers his "Atoms for Peace" speech to the United Nations General Assembly in New York. Source: IAEA

In the early days of nuclear energy development, the government led the charge, funding the research, development, and design of 52 different reactors at the Idaho laboratory’s National Reactor Testing Station alone, not to mention those that were being developed at other labs, like the one that was the subject of the paper Leslie and Mark read. With the help of the government, engineers were able to branch out in many different directions.

Soon enough, the designs were moving from paper to test reactors to deployment at breathtaking speed. The tiny Experimental Breeder Reactor 1, which went online in December 1951 at the Idaho National Lab, ushered in the age of nuclear energy.

Just two years later, President Dwight D. Eisenhower made his Atoms for Peace speech to the U.N., in which he declared that “The United States knows that peaceful power from atomic energy is no dream of the future. The capability, already proved, is here today.” Less than a year after that, Eisenhower waved a ceremonial "neutron wand" to signal a bulldozer in Shippingport, Pennsylvania to begin construction of the nation’s first commercial nuclear power plant.

1956: Reactor pressure vessel during construction at the Shippingport Atomic Power Station. Source: Wikipedia

By 1957 the Atoms for Peace program had borne fruit, and Shippingport was open for business. During the years that followed, the government, fulfilling Eisenhower’s dream, not only funded the research, it ran the labs, chose the technologies, and, eventually, regulated the reactors.

The U.S. would soon rapidly surpass not only its Cold War enemy, the Soviet Union, which had brought the first significant electricity-producing reactor online in 1954, but every other country seeking to deploy nuclear energy, including France and Canada. Much of the extraordinary progress in America’s development of nuclear energy technology can be credited to one specific government institution—the U.S. Navy.

Rickover’s choice has had enormous implications. To this day, the light water reactor remains the standard—the only type of reactor built or used for energy production in the United States and in most other countries as well. Research on other reactor types (like molten salt and lead) essentially ended for almost six decades, not to be revived until very recently.

Once light water reactors got the nod, the Atomic Energy Commission endorsed a cookie-cutter-like approach to building additional reactors that was very enticing to energy companies seeking to enter the atomic arena. Having a standardized light water reactor design meant quicker regulatory approval, economies of scale, and operating uniformity, which helped control costs and minimize uncertainty. And there was another upside to the light water reactors, at least back then: they produced a byproduct—plutonium. These days, we call that a problem: the remaining fissile material that must be protected from accidental discharge or proliferation and stored indefinitely. In the Cold War 1960s, however, that was seen as a benefit, because the leftover plutonium could be used to make nuclear weapons.

2005: An ICBM loaded into a silo of the former ICBM missile site, now the Titan Missile Museum. Source: Wikipedia

With the triumph of the light water reactor came a massive expansion of the domestic and global nuclear energy industries. In the 1960s and ‘70s, America’s technology, design, supply chain, and regulatory system dominated the production of all civilian nuclear energy on this side of the Iron Curtain. U.S. engineers drew the plans, U.S. companies like Westinghouse and GE built the plants, U.S. factories and mills made the parts, and the U.S. government’s Atomic Energy Commission set the global safety standards.

In this country, we built more than 100 light water reactors for commercial power production. Though no two American plants were identical, all of the plants constructed in that era were essentially the same—light water reactors running on uranium enriched to about 4 percent. By the end of the 1970s, in addition to the 100-odd reactors that had been built, 100 more were in the planning or early construction stage.

And then everything came to a screeching halt, thanks to a bizarre confluence of Hollywood and real life.

On March 16, 1979, The China Syndrome —starring Jane Fonda, Jack Lemmon, and Michael Douglas—hit theaters, frightening moviegoers with an implausible but well-told tale of a reactor meltdown and catastrophe, which had the potential, according to a character in the film, to render an area “the size of Pennsylvania permanently uninhabitable.” Twelve days later, the Number 2 reactor at the Three Mile Island plant in central Pennsylvania suffered an accident that caused the release of some nuclear coolant and a partial meltdown of the reactor core. After the governor ordered the evacuation of “pregnant women and preschool age children,” widespread panic followed, and tens of thousands of people fled in terror.

1979: Three Mile Island power station. Source: Wikipedia

But both the evacuation order and the fear were unwarranted. A massive investigation revealed that the release of radioactive materials was minimal and had posed no risk to human health. No one was injured or killed at Three Mile Island. What did die that day was America’s nuclear energy leadership. After Three Mile Island, plans for new plants then on the drawing board were scrapped or went under in a blizzard of public recrimination, legal action, and regulatory overreach by federal, state, and local officials. For example, the Shoreham plant on Long Island, which took nearly a decade to build and was completed in 1984, never opened, becoming one of the biggest and most expensive white elephants in human history.

The concrete "sarcophagus" built over the Chernobyl nuclear power plant's fourth reactor that exploded on April 26, 1986. Source: REUTERS

Chernobyl sarcophogi Magnum

The final, definitive blow to American nuclear energy was delivered in 1986, when the Soviets bungled their way into a genuine nuclear energy catastrophe: the disaster at the Chernobyl plant in Ukraine. It was man-made in its origin (risky decisions made at the plant led to the meltdown, and the plant itself was badly designed); widespread in its scope (Soviet reactors had no containment vessel, so the roof was literally blown off, the core was exposed, and a radioactive cloud covered almost the whole of Europe); and lethal in its impact (rescuers and area residents were lied to by the Soviet government, which denied the risk posed by the disaster, causing many needless deaths and illnesses and the hospitalization of thousands).

After Chernobyl, it didn’t matter that American plants were infinitely safer and better run. This country, which was awash in cheap and plentiful coal, simply wasn’t going to build more nuclear plants if it didn’t have to.

But now we have to.

The terrible consequences of climate change mean that we must find low- and zero-emitting ways of producing electricity.

November 2014: Leslie Dewan and Mark Massie at MIT. Source: Sareen Hairabedian, Brookings Institution

The Return of Nuclear Pioneers

Five new light water reactors are currently under construction in the U.S., but the safety concerns about them (largely unwarranted as they are) as well as their massive size, cost, complexity, and production of used fuel (“waste”) mean that there will probably be no large-scale return to the old style of reactor. What we need now is to go back to the future and build some of those plants that they dreamed up in the labs of yesterday.

Which is what Leslie and Mark are trying to do with Transatomic. Once they had their breakthrough moment and realized that they could fuel their reactor on nuclear waste material, they began to think seriously about founding a company. So they started doing what all entrepreneurial MIT grads do—they talked to venture capitalists. Once they got their initial funding, the two engineers knew that they needed someone with business experience, so they hired a CEO, Russ Wilcox, who had built and sold a very successful e-publishing company. At the time they approached him, Wilcox was in high demand, but after hearing Leslie and Mark give a TEDx talk about the environmental promise of advanced nuclear technology, he opted to go with Transatomic— because he thought it could help save the world.

November 1, 2014: Mark Massie and Leslie Dewan giving a TEDx talk . Source: Transatomic

In their talk, the two founders had explained that in today’s light water reactors, metal-clad uranium fuel rods are lowered into water in order to heat it and create steam to run the electric turbines. But the water eventually breaks down the metal cladding and then the rods must be replaced. The old rods become nuclear waste, which will remain radioactive for up to 100,000 years, and, under the current American system, must remain in storage for that period.

The genius of the Transatomic design is that, according to Mark’s simulations, their reactor could make use of almost all of the energy remaining in the rods that have been removed from the old light water reactors, while producing almost no waste of their own—just 2.5 percent as much as produced by a typical light water reactor. If they built enough molten salt reactors, Transatomic could theoretically consume not just the roughly 70,000 metric tons of nuclear waste currently stored at U.S. nuclear plants, but also the additional 2,000 metric tons that are produced each year.

Like all molten salt reactors, the Transatomic design is extraordinarily safe as well. That is more important than ever after the terror inspired by the disaster that occurred at the Fukushima light water reactor plant in 2011.When the tsunami knocked out the power for the pumps that provided the water required for coolant, the Fukushima plant suffered a partial core meltdown. In a molten salt reactor, by contrast, no externally supplied coolant would be needed, making it what Transatomic calls “walk away safe.” That means that, in the event of a power failure, no human intervention would be required; the reactor would essentially cool itself without water or pumps. With a loss of external electricity, the artificially chilled plug at the base of the reactor would melt, and the material in the core (salt and uranium fuel) would drain to a containment tank and cool within hours.

Leslie and Mark have also found materials that would boost the power output of a molten salt reactor by 30 times over the 1960s model. Their redesign means the reactor might be small and efficient enough to be built in a factory and moved by rail. (Current reactors are so large that they must be assembled on site.)

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Transatomic, as well as General Fusion and LPP Fusion, represent one branch of the new breed of nuclear pioneers—call them “the young guns.” Also included in this group are companies like Terrestrial Energy in Canada, which is developing an alternative version of the molten salt reactor; Flibe Energy, which is preparing for experiments on a liquid-thorium fluoride reactor; UPower, at work on a nuclear battery; and engineers who are incubating projects not just at MIT but at a number of other universities and labs. Thanks to their work, the next generator of reactors might just be developed by small teams of brilliant entrepreneurs.

Then there are the more established companies and individuals—call them the “old pros”—who have become players in the advanced nuclear game. These include the engineering giant Fluor, which recently bought a startup out of Oregon called NuScale Power. They are designing a new type of light water “Small Modular Reactor” that is integral (the steam generator is built in), small (it generates about 4 percent of the output of a large reactor and fits on the back of a truck), and sectional (it can be strung together with others to generate more power). In part because of its relatively familiar light water design, Fluor and a small modular reactor competitor, Babcock & Wilcox, are the only pioneers of the new generation of technology to have received government grants—for $226 million each—to fund their research.

Another of the “old pros,” the well-established General Atomics, in business since 1955, is combining the benefits of small modular reactors with a design that can convert nuclear waste into electricity and also produce large amounts of heat and energy for industrial applications. The reactor uses helium rather than water or molten salt as its coolant. Its advanced design, which they call the Energy Multiplier Module reactor, has the potential to revolutionize the industry.

Somewhere in between is TerraPower. While it’s run by young guns, it’s backed by the world’s second richest man (among others). But even Bill Gates’s money won’t be enough. Nuclear technology is too big, too expensive, and too complex to explore in a garage, real or metaphorical. TerraPower has said that a prototype reactor could cost up to $5 billion, and they are going to need some big machines to develop and test it.

So while Leslie, Mark, and others in their cohort may seem like the latest iteration of Silicon Valley hipster entrepreneurs, the work they’re trying to do cannot be accomplished by Silicon Valley VC-scale funding. There has to be substantial government involvement.

Unfortunately, the relatively puny grants to Fluor and Babcock & Wilcox are the federal government’s largest contribution to advanced nuclear development to date. At the moment, the rest are on their own.

The result is that some of the fledgling enterprises, like General Atomic and Gates’s TerraPower, have decamped for China. Others, like Leslie and Mark’s, are staying put in the United States (for now) and hoping for federal support.

UBritish Chancellor of the Exchequer George Osborne (2nd R) chats with workers beside Taishan Nuclear Power Joint Venture Co Ltd General Manager Guo Liming (3rd R) and EDF Energy CEO Vincent de Rivaz (R), in front of a nuclear reactor under construction at a nuclear power plant in Taishan, Guangdong province, October 17, 2013. Chinese companies will be allowed to take stakes in British nuclear projects, Osborne said on Thursday, as Britain pushes ahead with an ambitious target to expand nuclear energy. REUTERS/Bobby Yip (CHINA - Tags: POLITICS BUSINESS ENVIRONMENT SCIENCE TECHNOLOGY ENERGY) Source: REUTERS

June 2008: A nearly 200 ton nuclear reactor safety vessel is erected at the Indira Gandhi Centre for Atomic Research at Kalpakkam, near the southern Indian city of Chennai. Source: REUTERS/Babu (INDIA)

Missing in Action: The United States Government

There are American political leaders in both parties who talk about having an “all of the above” energy policy, implying that they want to build everything, all at once. But they don’t mean it, at least not really. In this country, we don’t need all of the above—virtually every American has access to electric power. We don’t want it—we have largely stopped building coal as well as nuclear plants, even though we could. And we don’t underwrite it—the public is generally opposed to the government being in the business of energy research, development, and demonstration (aka, RD&D).

In China, when they talk of “all of the above,” they do mean it. With hundreds of millions of Chinese living without electricity and a billion more demanding ever-increasing amounts of power, China is funding, building, and running every power project that they possibly can. This includes the nuclear sector, where they have about 29 big new light water reactors under construction. China is particularly keen on finding non-emitting forms of electricity, both to address climate change and, more urgently for them, to help slow the emissions of the conventional pollutants that are choking their cities in smog and literally killing their citizens.

Since (for better or for worse) China isn’t hung up on safety regulation, and there is zero threat of legal challenge to nuclear projects, plans can be realized much more quickly than in the West. That means that there are not only dozens of light water reactor plants going up in China, but also a lot of work on experimental reactors with advanced nuclear designs—like those being developed by General Atomic and TerraPower.

Given both the competitive threat from China and the potentially disastrous global effects of emissions-induced climate change, the U.S. government should be leaping back into the nuclear race with the kind of integrated response that it brought to the Soviet threat during the Cold War.

But it isn’t, at least not yet. Through years of stagnation, America lost—or perhaps misplaced—its ability to do big, bold things in nuclear science. Our national labs, which once led the world to this technology, are underfunded, and our regulatory system, which once set the standard of global excellence, has become overly burdensome, slow, and sclerotic.

The villains in this story are familiar in Washington: ideology, ignorance, and bureaucracy. Let’s start with Congress, currently sporting a well-earned 14 percent approval rating. On Capitol Hill, an unholy and unwitting alliance of right-wing climate deniers, small-government radicals, and liberal anti-nuclear advocates have joined together to keep nuclear lab budgets small. And since even naming a post office constitutes a huge challenge for this broken Congress, moving forward with the funding and regulation of a complex new technology seems well beyond its capabilities at the moment.

Then there is the federal bureaucracy, which has failed even to acknowledge that a new generation of reactors is on the horizon. It took the Nuclear Regulatory Commission (the successor to the Atomic Energy Commission) years to approve a design for the new light water reactor now being built in Georgia, despite the fact that it’s nearly identical to the 100 or so that preceded it. The NRC makes no pretense of being prepared to evaluate reactors cooled by molten salt or run on depleted uranium. And it insists on pounding these new round pegs into its old square holes, demanding that the new reactors meet the same requirements as the old ones, even when that makes no sense.

At the Department of Energy, their heart is in the right place. DOE Secretary Ernest Moniz is a seasoned political hand as well as an MIT nuclear physicist, and he absolutely sees the potential in advanced reactor designs. But, constrained by a limited budget, the department is not currently in a position to drive the kind of changes needed to bring advanced nuclear designs to market.

President Obama clearly believes in nuclear energy. In an early State of the Union address he said, “We need more production, more efficiency, more incentives. And that means building a new generation of safe, clean nuclear power plants in this country." But the White House has been largely absent from the nuclear energy discussion in recent years. It is time for it to reengage.

May 22, 1957: A GE supervisor inspects the instrument panel for the company’s boiling water power reactor in Pleasanton, CA. Source: Bettmann/Corbis/AP Images

Getting the U.S. Back in the Race

So what, exactly, do the people running the advanced nuclear companies need from the U.S. government? What can government do to help move the technology off of their computers and into the electricity production marketplace?

First, they need a practical development path. Where is Bill Gates going to test TerraPower’s brilliant new reactor designs? Because there are no appropriate government-run facilities in the United States, he is forced to make do in China. He can’t find this ideal. Since more than two-thirds of Microsoft Windows operating systems used in China are pirated, he is surely aware that testing in China greatly increases the risk of intellectual property theft.

Thus, at the center of a development path would be an advanced reactor test bed facility, run by the government, and similar to what we had at the Idaho National Lab in 1960s. Such a facility, which would be open to all of the U.S. companies with reactors in development, would allow any of them to simply plug in their fuel and materials and run their tests

But advanced test reactors of the type we need are expensive and complex. The old one at the Idaho lab can’t accommodate the radiation and heat levels required by the new technologies. Japan has a newer one, but it shut down after Fukushima. China and Russia each have them, and France is building one that should be completed in 2016. But no one has the cutting-edge, truly advanced incubator space that the new firms need to move toward development.

Second is funding. Mark and Leslie have secured some venture capital, but Transatomic will need much more money in order to perform the basic engineering on an advanced test reactor and, eventually, to construct demonstration reactors. Like all startups, Transatomic faces a “Valley of Death” between concept and deployment; with nuclear technology’s enormous costs and financial risk, it’s more like a “Grand Canyon of Death.” Government must play a big role in bridging that canyon, as it did in the early days of commercial nuclear energy development, beginning with the first light water reactor at Shippingport.

For Further Reading

President Obama, It's Time to Act on Energy Policy November 2014, Charles Ebinger

Transforming the Electricity Portfolio: Lessons from Germany and Japan in Deploying Renewable Energy September 2014, John Banks, Charles Ebinger, and Alisa Schackmann

The Road Ahead for Japanese Energy June 2014

Planet Policy A blog about the intersection of energy and climate policy

Third, they need a complete rethinking of the NRC approach to regulating advanced nuclear technology. How can the brand new Flibe Energy liquid-thorium fluoride reactor technology be forced to meet the same criteria as the typical light water reactor? The NRC must be flexible enough to accommodate technology that works differently from the light water reactors it is familiar with. For example, since Transatomic’s reactor would run at normal atmospheric pressure, unlike a light water reactor, which operates under vastly greater pressure, Mark and Leslie shouldn’t be required to build a huge and massively expensive containment structure around their reactors. Yet the NRC has no provision allowing them to bypass that requirement. If that doesn’t change, there is no way that Transatomic will be able to bring its small, modular, innovative reactors to market.

In addition, the NRC must let these technologies develop organically. They should permit Transatomic and the others to build and operate prototype reactors before they are fully licensed, allowing them to demonstrate their safety and reliability with real-world stress tests, as opposed to putting them through never-ending rounds of theoretical discussion and negotiation with NRC testers.

None of this is easy. The seriousness of the climate change threat is not universally acknowledged in Washington. Federal budgets are now based in the pinched, deficit-constrained present, not the full employment, high-growth economy of the 1950s. And the NRC, in part because of its mission to protect public safety, is among the most change-averse of any federal agency.

But all of this is vital. Advanced nuclear technology could hold a key to fighting climate change. It could also result in an enormous boon to the American economy. But only if we get there first.

Who Will Own the Nuclear Power Future?

Josh Freed, Third Way's clean energy vice president, works on developing ways the federal government can help accelerate the private sector's adoption of clean energy and address climate change. He has served as a senior staffer on Capitol Hill and worked in various public advocacy and political campaigns, including advising the senior leadership of the Bill & Melinda Gates Foundation.

Nuclear energy is at a crossroads. One path sends brilliant engineers like Leslie and Mark forward, applying their boundless skills and infectious optimism to world-changing technologies that have the potential to solve our energy problems while also fueling economic development and creating new jobs. The other path keeps the nuclear industry locked in unadaptable technologies that will lead, inevitably, to a decline in our major source of carbon-free energy.

The chance to regain our leadership in nuclear energy, to walk on the path once trod by the engineers and scientists of the 1950s and ‘60s, will not last forever. It is up to those who make decisions on matters concerning funding and regulation to strike while the iron is hot.

This is not pie-in-the-sky thinking—we have done this before. At the dawn of the nuclear age, we designed and built reactors that tested the range of possibility. The blueprints then languished on the shelves of places like the MIT library for more than fifty years until Leslie Dewan, Mark Massie, and other brilliant engineers and scientists thought to revive them. With sufficient funding and the appropriate technical and political leadership, we can offer the innovators and entrepreneurs of today the chance to use those designs to power the future.

Join the conversation on Twitter using #BrookingsEssay or share this on Facebook .

This Essay is also available as an eBook from these online retailers: Amazon Kindle , Barnes & Noble , Apple iTunes , Google Play , Ebooks.com , and on Kobo .

This article was written by Josh Freed, vice president of the Clean Energy Program at Third Way. The author has not personally received any compensation from the nuclear energy industry. In the spirit of maximum transparency, however, the author has disclosed that several entities mentioned in this article are associated in varying degrees with Third Way. The Nuclear Energy Institute (NEI) and Babcock & Wilcox have financially supported Third Way. NEI includes TerraPower, Babcock & Wilcox, and Idaho National Lab among its members, as well as Fluor on its Board of Directors. Transatomic is not a member of NEI, but Dr. Leslie Dewan has appeared in several of its advertisements. Third Way is also working with and has received funding from Ray Rothrock, although he was not consulted on the contents of this essay. Third Way previously held a joint event with the Idaho National Lab that was unrelated to the subject of this essay.

* The essay originally also referred to Hitachi buying GE's nuclear arm. GE owns 60 percent of Hitachi.

Like other products of the Institution, The Brookings Essay is intended to contribute to discussion and stimulate debate on important issues. The views are solely those of the author.

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Essay on Nuclear Energy

Students are often asked to write an essay on Nuclear Energy in their schools and colleges. And if you’re also looking for the same, we have created 100-word, 250-word, and 500-word essays on the topic.

Let’s take a look…

100 Words Essay on Nuclear Energy

Introduction.

Nuclear energy is a powerful source of energy generated from atomic reactions. It is created from the splitting of atoms, a process known as nuclear fission.

Production of Nuclear Energy

Nuclear energy is produced in nuclear power plants. These plants use uranium, a mineral, as fuel. The heat generated from nuclear fission is used to create steam, which spins a turbine to generate electricity.

Benefits of Nuclear Energy

Nuclear energy is very efficient. It produces a large amount of energy from a small amount of uranium. It also does not emit harmful greenhouse gases, making it environmentally friendly.

Drawbacks of Nuclear Energy

Despite its benefits, nuclear energy has drawbacks. The most significant is the production of radioactive waste, which is dangerous and hard to dispose of. It also poses a risk of nuclear accidents.

Also check:

• Advantages and Disadvantages of Nuclear Energy
• Paragraph on Nuclear Energy

250 Words Essay on Nuclear Energy

Introduction to nuclear energy.

Nuclear energy, a powerful and complex energy source, is derived from splitting atoms in a process known as nuclear fission. Its significant energy output and low greenhouse gas emissions make it a potential solution to the world’s increasing energy demands.

Production and Efficiency

Nuclear power plants operate by using nuclear fission to generate heat, which then produces steam to turn turbines and generate electricity. The efficiency of nuclear energy is unparalleled, with one kilogram of uranium-235 producing approximately three million times the energy of a kilogram of coal.

Environmental Implications

Nuclear energy is often considered a clean energy source due to its minimal carbon footprint. However, the production of nuclear energy also results in radioactive waste, the disposal of which poses significant environmental challenges.

Security and Ethical Concerns

The utilization of nuclear energy is not without its risks. Accidents like those at Chernobyl and Fukushima have highlighted the potential for catastrophic damage. Furthermore, the proliferation of nuclear technology raises ethical concerns about its potential misuse for military purposes.

Future of Nuclear Energy

The future of nuclear energy hinges on technological advancements and policy decisions. The development of safer, more efficient reactors and sustainable waste disposal methods could mitigate some of the risks associated with nuclear energy. Additionally, international cooperation is crucial to ensure the peaceful and secure use of nuclear technology.

In conclusion, nuclear energy presents a potent solution to the energy crisis, but it also brings significant challenges. Balancing its benefits against the associated risks requires careful consideration and responsible action.

500 Words Essay on Nuclear Energy

Nuclear energy, a powerful and complex form of energy, is derived from splitting atoms in a reactor to heat water into steam, turn a turbine, and generate electricity. Ninety-four nuclear reactors in 28 states, approximately 20% of total electricity production in the United States, are powered by this process. Globally, nuclear energy is a significant source of power, contributing to about 10% of the world’s total electricity supply.

The Mechanics of Nuclear Energy

Nuclear energy is produced through a process called nuclear fission. This process involves the splitting of uranium atoms in a nuclear reactor, which releases an immense amount of energy in the form of heat and radiation. The heat generated is then used to boil water, create steam, and power turbines that generate electricity.

The fuel for nuclear reactors, uranium, is abundant and can be found in many parts of the world, making nuclear energy a viable option for countries without significant fossil fuel resources. Moreover, the energy produced by a single uranium atom split is a million times greater than that from burning a single coal or gas molecule, making nuclear power a highly efficient energy source.

Pros and Cons of Nuclear Energy

One of the main advantages of nuclear energy is its low greenhouse gas emission. It emits a fraction of the carbon dioxide and other greenhouse gases compared to fossil fuel-based energy sources, making it a potential solution to combat climate change.

Nuclear energy is also reliable. Unlike renewable energy sources like wind and solar, nuclear power plants can operate continuously and are not dependent on weather conditions. They can provide a steady, uninterrupted supply of electricity, which is crucial for the functioning of modern societies.

However, nuclear energy also has significant drawbacks. The risk of nuclear accidents, while statistically low, can have devastating and long-lasting impacts, as seen in Chernobyl and Fukushima. Additionally, the disposal of nuclear waste poses a serious challenge due to its long-term radioactivity.

The Future of Nuclear Energy

The future of nuclear energy is uncertain. On one hand, the demand for low-carbon energy sources to combat climate change could lead to an increase in the use of nuclear energy. On the other hand, concerns about nuclear safety, waste disposal, and the high costs of building new nuclear power plants could hinder its growth.

Advancements in nuclear technology, such as the development of small modular reactors and fourth-generation reactors, could address some of these concerns. These technologies promise to be safer, more efficient, and produce less nuclear waste, potentially paving the way for a nuclear renaissance.

In conclusion, nuclear energy presents a compelling paradox. It offers a high-energy, low-carbon alternative to fossil fuels, yet it carries significant risks and challenges. As we move towards a more sustainable future, it is crucial to weigh these factors and make informed decisions about the role of nuclear energy in our global energy mix.

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Nuclear energy is released from the nucleus of atoms through the processes of fission or fusion.

Contributors

What is nuclear.

Nuclear energy is the energy held in the nucleus of an atom; it can be obtained through two types of reactions –  fission  and  fusion 1 .

Nuclear fission produces energy through the splitting of atoms, which releases heat  energy  that can generate steam and then be used to turn a  turbine to produce electricity. 2 All of today’s nuclear plants use fission to generate electricity . The fuel most commonly used for fission is uranium, although additional elements such as plutonium or thorium can be used.

Nuclear fusion is a nuclear reaction in which two or more atomic nuclei collide at a very high speeds and join to form a new type of atomic nucleus. During this process, matter is not conserved because some of the matter of the fusing nuclei is converted into photons, which produces usable energy.  This process is what allows the sun and stars to give off energy. Fusion power offers the prospect of an almost inexhaustible source of energy for future generations; however, creating the conditions for nuclear fusion presents a potentially insurmountable scientific and engineering challenge 3 . A recent experiment  has shown that nuclear fusion can be achieved, however, it has not yet been successfully demonstrated on a commercial scale.

Today, nuclear power plants account for 11% of global electricity generation with about 80% of that installed capacity being in OECD countries 4 All of this capacity is nuclear fission.

Nuclear energy, through fission, can release 1 million times more energy per atom than  fossil fuels 5 . It can also be integrated into  electricity grids , which currently utilize fossil fuel generation, with few changes to existing infrastructure.

Nuclear has large power-generating capacity and low operating costs, making it ideal for base load generation. However, up front capital costs are intensive and present financial risk to investors given the extended time frames power plants must operate to recuperate their costs [6] .

Nuclear energy does not emit greenhouse gas emissions. For this reason, it is often seen as a substitute for fossil fuel energy generation and a solution for mitigating climate change.

However, nuclear fission has a wide variety of environmental and health issues associated with electricity generation. The largest concern is the generation of radioactive wastes such as uranium mill tailings, spent (used) reactor fuel, and other radioactive wastes. Some of these materials can remain radioactive and hazardous to both human health and the environment for thousands of years. Several large nuclear meltdowns in history released radioactive waste that had lasting negative impacts on the environment and surrounding communities. This has made nuclear fission technologies controversial.

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• Nuclear Energy (2015). What is nuclear energy? http://nuclear-energy.net/what-is-nuclear-energy ↩
• United States Environmental Protection Agency (2015). Nuclear energy. http://www.epa.gov/cleanenergy/energy-and-you/affect/nuclear.html ↩
• World Nuclear Association (n.d.). Nuclear fusion power. http://www.world-nuclear.org/info/current-and-future-generation/nuclear-fusion-power/  ↩
• World Energy Outlook (2014). Nuclear power: Retreat, revival or renaissance? http://www.iea.org/media/news/2014/press/141112_WEO_FactSheet_Nuclear.pdf ↩
• MacKay, D.J.C. (2018). Sustainable energy without the hot air. http://www.withouthotair.com .  ↩
• Department of Energy and Climate Change (2013). Investing in renewable technologies: CFD contract terms and strike price. https://www.gov.uk/government/publications/investing-in-renewable-technologies-cfd-contract-terms-and-strike-prices ↩

Nuclear energy protects air quality by producing massive amounts of carbon-free electricity. It powers communities in 28 U.S. states and contributes to many non-electric applications, ranging from the  medical field to space exploration .

The Office of Nuclear Energy within the U.S. Department of Energy (DOE) focuses its research primarily on maintaining the existing fleet of reactors, developing new advanced reactor technologies, and improving the nuclear fuel cycle to increase the sustainability of our energy supply and strengthen the U.S. economy.

Below are some of the main advantages of nuclear energy and the challenges currently facing the industry today.

Advantages of Nuclear Energy

Clean Energy Source

Nuclear is the largest source of clean power in the United States. It generates nearly 800 billion kilowatt hours of electricity each year and produces more than half of the nation’s emissions-free electricity. This avoids more than 470 million metric tons of carbon each year, which is the equivalent of removing 100 million cars off of the road.

Creates Jobs

The nuclear industry supports nearly half a million jobs in the United States and contributes an estimated $60 billion to the U.S. gross domestic product each year. U.S. nuclear plants can employ up to 700 workers with salaries that are 30% higher than the local average. They also contribute billions of dollars annually to local economies through federal and state tax revenues.

Supports National Security

A strong civilian nuclear sector is essential to U.S. national security and energy diplomacy. The United States must maintain its global leadership in this arena to influence the peaceful use of nuclear technologies. The U.S. government works with countries in this capacity to build relationships and develop new opportunities for the nation’s nuclear technologies.

Challenges of Nuclear Energy

Public Awareness

Commercial nuclear power is sometimes viewed by the general public as a dangerous or unstable process. This perception is often based on three global nuclear accidents, its false association with nuclear weapons, and how it is portrayed on popular television shows and films.

DOE and its national labs are working with industry to develop new reactors and fuels that will increase the overall performance of these technologies and reduce the amount of nuclear waste that is produced.  

DOE also works to provide accurate, fact-based information about nuclear energy through its social media and STEM outreach efforts to educate the public on the benefits of nuclear energy.

Used Fuel Transportation, Storage and Disposal

Many people view used fuel as a growing problem and are apprehensive about its transportation, storage, and disposal. DOE is responsible for the eventual disposal and associated transport of all commercial used fuel , which is currently securely stored at 76 reactor or storage sites in 34 states. For the foreseeable future, this fuel can safely remain at these facilities until a permanent disposal solution is determined by Congress.

DOE is currently evaluating nuclear power plant sites and nearby transportation infrastructure to support the eventual transport of used fuel away from these sites. It is also developing new, specially designed railcars to support large-scale transport of used fuel in the future.

Constructing New Power Plants

Building a nuclear power plant can be discouraging for stakeholders. Conventional reactor designs are considered multi-billion dollar infrastructure projects. High capital costs, licensing and regulation approvals, coupled with long lead times and construction delays, have also deterred public interest.

Microreactor (left) - Small Modular Reactor (right)

DOE is rebuilding its nuclear workforce by  supporting the construction  of two new reactors at Plant Vogtle in Waynesboro, Georgia. The units are the first new reactors to begin construction in the United States in more than 30 years. The expansion project will support up to 9,000 workers at peak construction and create 800 permanent jobs at the facility when the new units begin operation in 2023.

DOE is also supporting the development of smaller reactor designs, such as  microreactors  and  small modular reactors , that will offer even more flexibility in size and power capacity to the customer. These factory-built systems are expected to dramatically reduce construction timelines and will make nuclear more affordable to build and operate.

High Operating Costs

Challenging market conditions have left the nuclear industry struggling to compete. DOE’s  Light Water Reactor Sustainability (LWRS) program  is working to overcome these economic challenges by modernizing plant systems to reduce operation and maintenance costs, while improving performance. In addition to its materials research that supports the long-term operation of the nation’s fleet of reactors, the program is also looking to diversify plant products through non-electric applications such as water desalination and  hydrogen production .

To further improve operating costs. DOE is also working with industry to develop new fuels and cladding known as  accident tolerant fuels . These new fuels could increase plant performance, allowing for longer response times and will produce less waste. Accident tolerant fuels could gain widespread use by 2025.

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• v.45(Suppl 1); 2016 Jan

Nuclear power in the 21st century: Challenges and possibilities

Akos horvath.

MTA Centre for Energy Research, KFKI Campus, P.O.B. 49, Budapest 114, 1525 Hungary

Elisabeth Rachlew

Department of Physics, Royal Institute of Technology, KTH, 10691 Stockholm, Sweden

The current situation and possible future developments for nuclear power—including fission and fusion processes—is presented. The fission nuclear power continues to be an essential part of the low-carbon electricity generation in the world for decades to come. There are breakthrough possibilities in the development of new generation nuclear reactors where the life-time of the nuclear waste can be reduced to some hundreds of years instead of the present time-scales of hundred thousand of years. Research on the fourth generation reactors is needed for the realisation of this development. For the fast nuclear reactors, a substantial research and development effort is required in many fields—from material sciences to safety demonstration—to attain the envisaged goals. Fusion provides a long-term vision for an efficient energy production. The fusion option for a nuclear reactor for efficient production of electricity has been set out in a focussed European programme including the international project of ITER after which a fusion electricity DEMO reactor is envisaged.

Introduction

All countries have a common interest in securing sustainable, low-cost energy supplies with minimal impact on the environment; therefore, many consider nuclear energy as part of their energy mix in fulfilling policy objectives. The discussion of the role of nuclear energy is especially topical for industrialised countries wishing to reduce carbon emissions below the current levels. The latest report from IPCC WGIII ( 2014 ) (see Box 1 for explanations of all acronyms in the article) says: “Nuclear energy is a mature low-GHG emission source of base load power, but its share of global electricity has been declining since 1993. Nuclear energy could make an increasing contribution to low-carbon energy supply, but a variety of barriers and risks exist ”.

Demand for electricity is likely to increase significantly in the future, as current fossil fuel uses are being substituted by processes using electricity. For example, the transport sector is likely to rely increasingly on electricity, whether in the form of fully electric or hybrid vehicles, either using battery power or synthetic hydrocarbon fuels. Here, nuclear power can also contribute, via generation of either electricity or process heat for the production of hydrogen or other fuels.

In Europe, in particular, the public opinion about safety and regulations with nuclear power has introduced much critical discussions about the continuation of nuclear power, and Germany has introduced the “Energiewende” with the goal to close all their nuclear power by 2022. The contribution of nuclear power to the electricity production in the different countries in Europe differs widely with some countries having zero contribution (e.g. Italy, Lithuania) and some with the major part comprising nuclear power (e.g. France, Hungary, Belgium, Slovakia, Sweden).

Current status

The use of nuclear energy for commercial electricity production began in the mid-1950s. In 2013, the world’s 392 GW of installed nuclear capacity accounted for 11 % of electricity generation produced by around 440 nuclear power plants situated in 30 countries (Fig.  1 ). This share has declined gradually since 1996, when it reached almost 18 %, as the rate of new nuclear additions (and generation) has been outpaced by the expansion of other technologies. After hydropower, nuclear is the world’s second-largest source of low-carbon electricity generation (IEA 2014 1 ).

Total number of operating nuclear reactors worldwide. The total number of reactors also include six in Taiwan (source: IAEA 2015) ( https://www.iaea.org/newscenter/focus/nuclear-power )

The Country Nuclear Power Profiles (CNPP 2 ) compiles background information on the status and development of nuclear power programmes in member states. The CNPP’s main objectives are to consolidate information about the nuclear power infrastructures in participating countries, and to present factors related to the effective planning, decision-making and implementation of nuclear power programmes that together lead to safe and economical operations of nuclear power plants.

Within the European Union, 27 % of electricity production (13 % of primary energy) is obtained from 132 nuclear power plants in January 2015 (Fig.  1 ). Across the world, 65 new reactors are under construction, mainly in Asia (China, South Korea, India), and also in Russia, Slovakia, France and Finland. Many other new reactors are in the planning stage, including for example, 12 in the UK.

Apart from one first Generation “Magnox” reactor still operating in the UK, the remainder of the operating fleet is of the second or third Generation type (Fig.  2 ). The predominant technology is the Light Water Reactor (LWR) developed originally in the United States by Westinghouse and then exploited massively by France and others in the 1970s as a response to the 1973 oil crisis. The UK followed a different path and pursued the Advanced Gas-cooled Reactor (AGR). Some countries (France, UK, Russia, Japan) built demonstration scale fast neutron reactors in the 1960s and 70s, but the only commercial reactor of this type currently operating is in Russia.

Nuclear reactor generations from the pioneering age to the next decade (reproduced with permission from Ricotti 2013 )

Future evolution

The fourth Generation reactors, offering the potential of much higher energy recovery and reduced volumes of radioactive waste, are under study in the framework of the “Generation IV International Forum” (GIF) 3 and the “International Project on Innovative Nuclear Reactors and Fuel Cycles” (INPRO). The European Commission in 2010 launched the European Sustainable Nuclear Industrial Initiative (ESNII), which will support three Generation IV fast reactor projects as part of the EU’s plan to promote low-carbon energy technologies. Other initiatives supporting biomass, wind, solar, electricity grids and carbon sequestration are in parallel. ESNII will take forward: the Astrid sodium-cooled fast reactor (SFR) proposed by France, the Allegro gas-cooled fast reactor (GFR) supported by central and eastern Europe and the MYRRHA lead- cooled fast reactor (LFR) technology pilot proposed by Belgium.

The generation of nuclear energy from uranium produces not only electricity but also spent fuel and high-level radioactive waste (HLW) as a by-product. For this HLW, a technical and socially acceptable solution is necessary. The time scale needed for the radiotoxicity of the spent fuel to drop to the level of natural uranium is very long (i.e. of the order of 200 000–300 000 years). The preferred solution for disposing of spent fuel or the HLW resulting from classical reprocessing is deep geological storage. Whilst there are no such geological repositories operating yet in the world, Sweden, Finland and France are on track to have such facilities ready by 2025 (Kautsky et al. 2013 ). In this context it should also be mentioned that it is only for a minor fraction of the HLW that recycling and transmutation is required since adequate separation techniques of the fuel can be recycled and again fed through the LWR system.

The “Strategic Energy Technology Plan” (SET-Plan) identifies fission energy as one of the contributors to the 2050 objectives of a low-carbon energy mix, relying on the Generation-3 reactors, closed fuel cycle and the start of implementation of Generation IV reactors making nuclear energy more sustainable. The EU Energy Roadmap 2050 provides decarbonisation scenarios with different assumptions from the nuclear perspective: two scenarios contemplate a nuclear phase-out by 2050, whilst three others consider that 15–20 % of electricity will be produced by nuclear energy. If by 2050 a generation capacity of 20 % nuclear electricity (140 GWe) is to be secured, 100–120 nuclear power units will have to be built between now and 2050, the precise number depending on the power rating (Garbil and Goethem 2013 ).

Despite the regional differences in the development plans, the main questions are of common interest to all countries, and require solutions in order to maintain nuclear power in the power mix of contributing to sustainable economic growth. The questions include (i) maintaining safe operation of the nuclear plants, (ii) securing the fuel supplies, (iii) a strategy for the management of radioactive waste and spent nuclear fuel.

Safety and non-proliferation risks are managed in accordance with the international rules issued both by IAEA and EURATOM in the EU. The nuclear countries have signed the corresponding agreements and the majority of them have created the necessary legal and regulatory structure (Nuclear Safety Authority). As regards radioactive wastes, particularly high-level wastes (HLW) and spent fuel (SF) most of the countries have long-term policies. The establishment of new nuclear units and the associated nuclear technology developments offer new perspectives, which may need reconsideration of fuel cycle policies and more active regional and global co-operation.

Open and closed fuel cycle

In the frame of the open fuel cycle, the spent fuel will be taken to final disposal without recycling. Deep geological repositories are the only available option for isolating the highly radioactive materials for a very long time from the biosphere. Long-term (80–100 years) near soil intermediate storages are realised in e.g. France and the Netherlands which will allow for permanent access and inspection. The main advantage of the open fuel cycle is its simplicity. The spent fuel assemblies are first stored in interim storage for several years or decades, then they will be placed in special containers and moved into deep underground storage facilities. The technology for producing such containers and for excavation of the underground system of tunnels exists today (Hózer et al. 2010 ; Kautsky et al. 2013 ).

The European Academies Science Advisory Board recently released the report on “Management of spent nuclear fuel and its waste” (EASAC 2014 ). The report discusses the challenges associated with different strategies to manage spent nuclear fuel, in respect of both open cycles and steps towards closing the nuclear fuel cycle. It integrates the conclusions on the issues raised on sustainability, safety, non-proliferation and security, economics, public involvement and on the decision-making process. Recently Vandenbosch et al. ( 2015 ) critically discussed the issue of confidence in the indefinite storage of nuclear waste. One complication of the nuclear waste storage problem is that the minor actinides represent a high activity (see Fig.  3 ) and pose non-proliferation issues to be handled safely in a civil used plant. This might be a difficult challenge if the storage is to be operated economically together with the fuel fabrication.

Radiotoxicity of radioactive waste

The open (or ‘once through’) cycle only uses part of the energy stored in the fuel, whilst effectively wasting substantial amounts of energy that could be recovered through recycling. The conventional closed fuel cycle strategy uses the reprocessing of the spent fuel following interim storage. The main components which can be further utilised (U and Pu) are recycled to fuel manufacturing (MOX (Mixed Oxide) fuel fabrication), whilst the smaller volume of residual waste in appropriately conditioned form—e.g. vitrified and encapsulated—is disposed of in deep geological repositories.

The advanced closed fuel cycle strategy is similar to the conventional one, but within this strategy the minor actinides are also removed during reprocessing. The separated isotopes are transmuted in combination with power generation and only the net reprocessing wastes and those conditioned wastes generated during transmutation will be, following appropriate encapsulation, disposed of in deep geological repositories. The main factor that determines the overall storage capacity of a long-term repository is the heat content of nuclear waste, not its volume. During the anticipated repository time, the specific heat generated during the decay of the stored HLW must always stay below a dedicated value prescribed by the storage concept and the geological host information. The waste that results from reprocessing spent fuel from thermal reactors has a lower heat content (after a period of cooling) than does the spent fuel itself. Thus, it can be stored more densely.

A modern light water reactor of 1 GWe capacity will typically discharge about 20–25 tonnes of irradiated fuel per year of operation. About 93–94 % of the mass of typical uranium oxide irradiated fuel comprises uranium (mostly 238 U), with about 4–5 % fission products and ~1 % plutonium. About 0.1–0.2 % of the mass comprises minor actinides (neptunium, americium and curium). These latter elements accumulate in nuclear fuel because of neutron capture, and they contribute significantly to decay heat loading and neutron output, as well as to the overall radiotoxic hazard of spent fuel. Although the total minor actinide mass is relatively small—20 to 25 kg per year from a 1 GWe LWR—it has a disproportionate impact on spent fuel disposal because of its long radioactive decay times (OECD Nuclear Energy Agency 2013 ).

Generation IV development

To address the issue of sustainability of nuclear energy, in particular the use of natural resources, fast neutron reactors (FNRs) must be developed, since they can typically multiply by over a factor 50 the energy production from a given amount of uranium fuel compared to current reactors. FNRs, just as today’s fleet, will be primarily dedicated to the generation of fossil-free base-load electricity. In the FNR the fuel conversion ratio (FCR) is optimised. Through hardening the spectrum a fast reactor can be designed to burn minor actinides giving a FCR larger than unity which allows breeding of fissile materials. FNRs have been operated in the past (especially the Sodium-cooled Fast Reactor in Europe), but today’s safety, operational and competitiveness standards require the design of a new generation of fast reactors. Important research and development is currently being coordinated at the international level through initiatives such as GIF.

In 2002, six reactor technologies were selected which GIF believe represent the future of nuclear energy. These were selected from the many various approaches being studied on the basis of being clean, safe and cost-effective means of meeting increased energy demands on a sustainable basis. Furthermore, they are considered being resistant to diversion of materials for weapons proliferation and secure from terrorist attacks. The continued research and development will focus on the chosen six reactor approaches. Most of the six systems employ a closed fuel cycle to maximise the resource base and minimise high-level wastes to be sent to a repository. Three of the six are fast neutron reactors (FNR) and one can be built as a fast reactor, one is described as epithermal, and only two operate with slow neutrons like today’s plants. Only one is cooled by light water, two are helium-cooled and the others have lead–bismuth, sodium or fluoride salt coolant. The latter three operate at low pressure, with significant safety advantage. The last has the uranium fuel dissolved in the circulating coolant. Temperatures range from 510 to 1000 °C, compared with less than 330 °C for today’s light water reactors, and this means that four of them can be used for thermochemical hydrogen production.

The sizes range from 150 to 1500 MWe, with the lead-cooled one optionally available as a 50–150 MWe “battery” with long core life (15–20 years without refuelling) as replaceable cassette or entire reactor module. This is designed for distributed generation or desalination. At least four of the systems have significant operating experience already in most respects of their design, which provides a good basis for further research and development and is likely to mean that they can be in commercial operation well before 2030. However, when addressing non-proliferation concerns it is significant that fast neutron reactors are not conventional fast breeders, i.e. they do not have a blanket assembly where plutonium-239 is produced. Instead, plutonium production happens to take place in the core, where burn-up is high and the proportion of plutonium isotopes other than Pu-239 remains high. In addition, new reprocessing technologies will enable the fuel to be recycled without separating the plutonium.

In January 2014, a new GIF Technology Roadmap Update was published. 4 It confirmed the choice of the six systems and focused on the most relevant developments of them so as to define the research and development goals for the next decade. It suggested that the Generation IV technologies most likely to be deployed first are the SFR, the lead-cooled fast reactor (LFR) and the very high temperature reactor technologies. The molten salt reactor and the GFR were shown as furthest from demonstration phase.

Europe, through sustainable nuclear energy technology platform (SNETP) and ESNII, has defined its own strategy and priorities for FNRs with the goal to demonstrate Generation IV reactor technologies that can close the nuclear fuel cycle, provide long-term waste management solutions and expand the applications of nuclear fission beyond electricity production to hydrogen production, industrial heat and desalination; The SFR as a proven concept, as well as the LFR as a short-medium term alternative and the GFR as a longer-term alternative technology. The French Commissariat à l’Energie Atomique (CEA) has chosen the development of the SFR technology. Astrid (Advanced Sodium Technological Reactor for Industrial Demonstration) is based on about 45 reactor-years of operational experience in France and will be rated 250 to 600 MWe. It is expected to be built at Marcoule from 2017, with the unit being connected to the grid in 2022.

Other countries like Belgium, Italy, Sweden and Romania are focussing their research and development effort on the LFR whereas Hungary, Czech Republic and Slovakia are investing in the research and development on GFR building upon the work initiated in France on GFR as an alternative technology to SFR. Allegro GFR is to be built in eastern Europe, and is more innovative. It is rated at 100 MWt and would lead to a larger industrial demonstration unit called GoFastR. The Czech Republic, Hungary and Slovakia are making a joint proposal to host the project, with French CEA support. Allegro is expected to begin construction in 2018 operate from 2025. The industrial demonstrator would follow it.

In mid-2013, four nuclear research institutes and engineering companies from central Europe’s Visegrád Group of Nations (V4) agreed to establish a centre for joint research, development and innovation in Generation IV nuclear reactors (the Czech Republic, Hungary, Poland and Slovakia) which is focused on gas-cooled fast reactors such as Allegro.

The MYRRHA (Multi-purpose hYbrid Research Reactor for High-tech Applications) 5 project proposed in Belgium by SCK•CEN could be an Experimental Technological Pilot Plant (ETPP) for the LFR technology. Later, it could become a European fast neutron technology pilot plant for lead and a multi-purpose research reactor. The unit is rated at 100 thermal MW and has started construction at SCK-CEN’s Mol site in 2014 planned to begin operation in 2023. A reduced-power model of Myrrha called Guinevere started up at Mol in March 2010. ESNII also includes an LFR technology demonstrator known as Alfred, also about 100 MWt, seen as a prelude to an industrial demonstration unit of about 600 MWe. Construction on Alfred could begin in 2017 and the unit could start operating in 2025.

Research and development topics to meet the top-level criteria established within the GIF forum in the context of simultaneously matching economics as well as stricter safety criteria set-up by the WENRA FNR demand substantial improvements with respect to the following issues:

• Primary system design simplification,
• Improved materials,
• Innovative heat exchangers and power conversion systems,
• Advanced instrumentation, in-service inspection systems,
• Enhanced safety,

and those for fuel cycle issues pertain to:

• Partitioning and transmutation,
• Innovative fuels (including minor actinide-bearing) and core performance,
• Advanced separation both via aqueous processes supplementing the PUREX process as well as pyroprocessing, which is mandatory for the reprocessing of the high MA-containing fuels,
• Develop a final depository.

Beyond the research and development, the demonstration projects mentioned above are planned in the frame of the SET-Plan ESNII for sustainable fission. In addition, supporting research infrastructures, irradiation facilities, experimental loops and fuel fabrication facilities, will need to be constructed.

Regarding transmutation, the accelerator-driven transmutation systems (ADS) technology must be compared to FNR technology from the point of view of feasibility, transmutation efficiency and cost efficiency. It is the objective of the MYRRHA project to be an experimental demonstrator of ADS technology. From the economical point of view, the ADS industrial solution should be assessed in terms of its contribution to closing the fuel cycle. One point of utmost importance for the ADS is its ability for burning larger amounts of minor actinides (the typical maximum in a critical FNR is about 2 %).

The concept of partitioning and transmutation (P&T) has three main goals: reduce the radiological hazard associated with spent fuel by reducing the inventory of minor actinides, reduce the time interval required to reach the radiotoxicity of natural uranium and reduce the heat load of the HLW packages to be stored in the geological disposal hence reducing the foot print of the geological disposal.

Advanced management of HLW through P&T consists in advanced separation of the minor actinides (americium, curium and neptunium) and some fission products with a long half-life present in the nuclear waste and their transmutation in dedicated burners to reduce the radiological and heat loads on the geological disposal. The time scale needed for the radiotoxicity of the waste to drop to the level of natural uranium will be reduced from a ‘geological’ value (300 000 years) to a value that is comparable to that of human activities (few hundreds of years) (OECD/NEA 2006 ; OECD 2012 ; PATEROS 2008 6 ). Transmutation of the minor actinides is achieved through fission reactions and therefore fast neutrons are preferred in dedicated burners.

At the European level, four building blocks strategy for Partitioning and Transmutation have been identified. Each block poses a serious challenge in terms of research & development to be done in order to reach industrial scale deployment. These blocks are:

• Demonstration of advanced reprocessing of spent nuclear fuel from LWRs, separating Uranium, Plutonium and Minor Actinides;
• Demonstration of the capability to fabricate at semi-industrial level dedicated transmuter fuel heavily loaded in minor actinides;
• Design and construct one or more dedicated transmuters;
• Fabrication of new transmuter fuel together with demonstration of advanced reprocessing of transmuter fuel.

MYRRHA will support this Roadmap by playing the role of an ADS prototype (at reasonable power level) and as a flexible irradiation facility providing fast neutrons for the qualification of materials and fuel for an industrial transmuter. MYRRHA will be not only capable of irradiating samples of such inert matrix fuels but also of housing fuel pins or even a limited number of fuel assemblies heavily loaded with MAs for irradiation and qualification purposes.

Options for nuclear fusion beyond 2050

Nuclear fusion research, on the basis of magnetic confinement, considered in this report, has been actively pursued in Europe from the mid-60s. Fusion research has the goal to achieve a clean and sustainable energy source for many generations to come. In parallel with basic high-temperature plasma research, the fusion technology programme is pursued as well as the economy of a future fusion reactor (Ward et al. 2005 ; Ward 2009 ; Bradshaw et al. 2011 ). The goal-oriented fusion research should be driven with an increased effort to be able to give the long searched answer to the open question, “will fusion energy be able to cover a major part of mankind’s electricity demand?”. ITER, the first fusion reactor to be built in France by the seven collaborating partners (Europe, USA, Russia, Japan, Korea, China, India) is hoped to answer most of the open physics and many of the remaining technology/material questions. ITER is expected to start operation of the first plasma around 2020 and D-T operation 2027.

The European fusion research has been successful through the organisation of EURATOM to which most countries in Europe belong (the fission programme is also included in EURATOM). EUROfusion, the European Consortium for the Development of Fusion Energy, manages European fusion research activities on behalf of EURATOM. The organisation of the research has resulted in a well-focused common fusion research programme. The members of the EUROfusion 7 consortium are 29 national fusion laboratories. EUROfusion funds all fusion research activities in accordance with the “EFDA Fusion electricity. Roadmap to the realisation of fusion energy” (EFDA 2012 , Fusion electricity). The Roadmap outlines the most efficient way to realise fusion electricity. It is the result of an analysis of the European Fusion Programme undertaken by all Research Units within EUROfusion’s predecessor agreement, the European Fusion Development Agreement, EFDA.

The most successful confinement concepts are toroidal ones like tokamaks and helical systems like stellarators (Wagner 2012 , 2013 ). To avoid drift losses, two magnetic field components are necessary for confinement and stability—the toroidal and the poloidal field component. Due to their superposition, the magnetic field winds helically around a system of nested toroids. In both cases, tokamak and stellarator, the toroidal field is produced by external coils; the poloidal field arises from a strong toroidal plasma current in tokamaks. In case of helical systems all necessary fields are produced externally by coils which have to be superconductive when steady-state operation is intended. Europe is constructing the most ambitious stellarator, Wendelstein 7-X in Germany. It is a fully optimised system with promising features. W7-X goes into operation in 2015. 8

Fusion research has now reached plasma parameters needed for a fusion reactor, even if not all parameters are reached simultaneously in a single plasma discharge (see Fig.  4 ). Plotted is the triple product n•τ E• T i composed of the density n, the confinement time τ E and the ion temperature T i . For ignition of a deuterium–tritium plasma, when the internal α-particle heating from the DT-reaction takes over and allows the external heating to be switched off, the triple product has to be about >6 × 10 21  m −3  s keV). The record parameters given as of today are shown together with the fusion experiment of its achievement in Fig.  4 . The achieved parameters and the missing factors to the ultimate goal of a fusion reactor are summarised below:

• Temperature: 40 keV achieved (JT-60U, Japan); the goal is surpassed by a factor of two
• Density n surpassed by factor 5 (C-mod,USA; LHD,Japan)
• Energy confinement time: a factor of 4 is missing (JET, Europe)
• Fusion triple product (see Fig.  4 : a factor of 6 is missing (JET, Europe)
• The first scientific goal is achieved: Q (fusion power/external heating power) ~1 (0,65) (JET, Europe)
• D-T operation without problems (TFTR (USA), JET, small tritium quantities have been used, however)
• Maximal fusion power for short pulse: 16 MW (JET)
• Divertor development (ASDEX, ASDEX-Upgrade, Germany)
• Design for the first experimental reactor complete (ITER, see below)
• The optimisation of stellarators (W7-AS, W7-X, Germany)

Progress in fusion parameters. Derived in 1955, the Lawson criterion specifies the conditions that must be met for fusion to produce a net energy output (1 keV × 12 million K). From this, a fusion “triple product” can be derived, which is defined as the product of the plasma ion density, ion temperature and energy confinement time. This product must be greater than about 6 × 10 21  keV m −3  s for a deuterium–tritium plasma to ignite. Due to the radioactivity associated with tritium, today’s research tokamaks generally operate with deuterium only ( solid dots ). The large tokamaks JET(EU) and TFTR(US), however, have used a deuterium–tritium mix ( open dots ). The rate of increase in tokamak performance has outstripped that of Moore’s law for the miniaturisation of silicon chips (Pitts et al. 2006 ). Many international projects (their names are given by acronyms in the figure) have contributed to the development of fusion plasma parameters and the progress in fusion research which serves as the basis for the ITER design

After 50 years of fusion research there is no evidence for a fundamental obstacle in the basic physics. But still many problems have to be overcome as detailed below:

Critical issues in fusion plasma physics based on magnetic confinement

• confine a plasma magnetically with 1000 m 3 volume,
• maintain the plasma stable at 2–4 bar pressure,
• achieve 15 MA current running in a fluid (in case of tokamaks, avoid instabilities leading to disruptions),
• find methods to maintain the plasma current in steady-state,
• tame plasma turbulence to get the necessary confinement time,
• develop an exhaust system (divertor) to control power and particle exhaust, specifically to remove the α-particle heat deposited into the plasma and to control He as the fusion ash.

Critical issues in fusion plasma technology

• build a system with 200 MKelvin in the plasma core and 4 Kelvin about 2 m away,
• build magnetic system at 6 Tesla (max field 12 Tesla) with 50 GJ energy,
• develop heating systems to heat the plasma to the fusion temperature and current drive systems to maintain steady-state conditions for the tokamak,
• handle neutron-fluxes of 2 MW/m 2 leading to 100 dpa in the surrounding material,
• develop low activation materials,
• develop tritium breeding technologies,
• provide high availability of a complex system using an appropriate remote handling system,
• develop the complete physics and engineering basis for system licensing.

The goals of ITER

The major goals of ITER (see Fig.  5 ) in physics are to confine a D-T plasma with α-particle self-heating dominating all other forms of plasma heating, to produce about ~500 MW of fusion power at a gain Q  = fusion power/external heating power, of about 10, to explore plasma stability in the presence of energetic α-particles, and to demonstrate ash-exhaust and burn control.

Schematic layout of the ITER reactor experiment (from www.iter.org )

In the field of technology, ITER will demonstrate fundamental aspects of fusion as the self-heating of the plasma by alpha-particles, show the essentials to a fusion reactor in an integrated system, give the first test a breeding blanket and assess the technology and its efficiency, breed tritium from lithium utilising the D-T fusion neutron, develop scenarios and materials with low T-inventories. Thus ITER will provide strong indications for vital research and development efforts necessary in the view of a demonstration reactor (DEMO). ITER will be based on conventional steel as structural material. Its inner wall will be covered with beryllium to surround the plasma with low-Z metal with low inventory properties. The divertor will be mostly from tungsten to sustain the high α-particle heat fluxes directed onto target plates situated inside a divertor chamber. An important step in fusion reactor development is the achievement of licensing of the complete system.

The rewards from fusion research and the realisation of a fusion reactor can be described in the following points:

• fusion has a tremendous potential thanks to the availability of deuterium and lithium as primary fuels. But as a recommendation, the fusion development has to be accelerated,

Fusion time strategy towards the fusion reactor on the net (EFDA 2012 , Fusion electricity. A roadmap to the realisation of fusion energy)

In addition, there is the fusion technology programme and its material branch, which ultimately need a neutron source to study the interaction with 14 MeV neutrons. For this purpose, a spallation source IFMIF is presently under design. As a recommendation, ways have to be found to accelerate the fusion development. In general, with ITER, IFMIF and the DEMO, the programme will move away from plasma science more towards technology orientation. After the ITER physics and technology programme—if successful—fusion can be placed into national energy supply strategies. With fusion, future generations can have access to a clean, safe and (at least expected of today) economic power source.

The fission nuclear power continues to be an essential part of the low-carbon electricity generation in the world for decades to come. There are breakthrough possibilities in the development of new generation nuclear reactors where the life-time of the nuclear waste can be reduced to some hundreds of years instead of the present time-scales of hundred thousand of years. Research on the fourth generation reactors is needed for the realisation of this development. For the fast nuclear reactors a substantial research and development effort is required in many fields—from material sciences to safety demonstration—to attain the envisaged goals. Fusion provides a long-term vision for an efficient energy production. The fusion option for a nuclear reactor for efficient production of electricity should be vigorously pursued on the international arena as well as within the European energy roadmap to reach a decision point which allows to critically assess this energy option.

Box 1 Explanations of abbreviations used in this article

Biographies.

is Professor in Energy Research and Director of MTA Center for Energy Research, Budapest, Hungary. His research interests are in the development of new fission reactors, new structural materials, high temperature irradiation resistance, mechanical deformation.

is Professor of Applied Atomic and Molecular Physics at Royal Institute of Technology, (KTH), Stockholm, Sweden. Her research interests are in basic atomic and molecular processes studied with synchrotron radiation, development of diagnostic techniques for analysing the performance of fusion experiments in particular development of photon spectroscopic diagnostics.

1 http://www.iea.org/ .

2 https://cnpp.iaea.org/pages/index.htm .

3 GenIV International forum: ( http://www.gen-4.org/index.html ).

4 https://www.gen-4.org/gif/jcms/c_60729/technology-roadmap-update-2013 .

5 http://myrrha.sckcen.be/ .

6 www.sckcen.be/pateros/ .

7 https://www.euro-fusion.org/ .

8 https://www.ipp.mpg.de/ippcms/de/pr/forschung/w7x/index.html .

Contributor Information

Akos Horvath, Email: [email protected] .

Elisabeth Rachlew, Email: es.htk@kre .

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Nuclear Power: Technical and Institutional Options for the Future (1992)

Chapter: 5 conclusions and recommendations, conclusions and recommendations.

The Committee was requested to analyze the technological and institutional alternatives to retain an option for future U.S. nuclear power deployment.

A premise of the Senate report directing this study is “that nuclear fission remains an important option for meeting our electric energy requirements and maintaining a balanced national energy policy.” The Committee was not asked to examine this premise, and it did not do so. The Committee consisted of members with widely ranging views on the desirability of nuclear power. Nevertheless, all members approached the Committee's charge from the perspective of what would be necessary if we are to retain nuclear power as an option for meeting U.S. electric energy requirements, without attempting to achieve consensus on whether or not it should be retained. The Committee's conclusions and recommendations should be read in this context.

The Committee's review and analyses have been presented in previous chapters. Here the Committee consolidates the conclusions and recommendations found in the previous chapters and adds some additional conclusions and recommendations based upon some of the previous statements. The Committee also includes some conclusions and recommendations that are not explicitly based upon the earlier chapters but stem from the considerable experience of the Committee members.

Most of the following discussion contains conclusions. There also are a few recommendations. Where the recommendations appear they are identified as such by bold italicized type.

GENERAL CONCLUSIONS

In 1989, nuclear plants produced about 19 percent of the United States ' electricity, 77 percent of France's electricity, 26 percent of Japan's electricity, and 33 percent of West Germany's electricity. However, expansion of commercial nuclear energy has virtually halted in the United States. In other countries, too, growth of nuclear generation has slowed or stopped. The reasons in the United States include reduced growth in demand for electricity, high costs, regulatory uncertainty, and public opinion. In the United States, concern for safety, the economics of nuclear power, and waste disposal issues adversely affect the general acceptance of nuclear power.

Electricity Demand

Estimated growth in summer peak demand for electricity in the United States has fallen from the 1974 projection of more than 7 percent per year to a relatively steady level of about 2 percent per year. Plant orders based on the projections resulted in cancellations, extended construction schedules, and excess capacity during much of the 1970s and 1980s. The excess capacity has diminished in the past five years, and ten year projections (at approximately 2 percent per year) suggest a need for new capacity in the 1990s and beyond. To meet near-term anticipated demand, bidding by non-utility generators and energy efficiency providers is establishing a trend for utilities acquiring a substantial portion of this new generating capacity from others. Reliance on non-utility generators does not now favor large scale baseload technologies.

Nuclear power plants emit neither precursors to acid rain nor gases that contribute to global warming, like carbon dioxide. Both of these environmental issues are currently of great concern. New regulations to address these issues will lead to increases in the costs of electricity produced by combustion of coal, one of nuclear power's main competitors. Increased costs for coal-generated electricity will also benefit alternate energy sources that do not emit these pollutants.

Major deterrents for new U.S. nuclear plant orders include high capital carrying charges, driven by high construction costs and extended construction times, as well as the risk of not recovering all construction costs.

Construction Costs

Construction costs are hard to establish, with no central source, and inconsistent data from several sources. Available data show a wide range of costs for U.S. nuclear plants, with the most expensive costing three times more (in dollars per kilowatt electric) than the least expensive in the same year of commercial operation. In the post-Three Mile Island era, the cost increases have been much larger. Considerable design modification and retrofitting to meet new regulations contributed to cost increases. From 1971 to 1980, the most expensive nuclear plant (in constant dollars) increased by 30 percent. The highest cost for a nuclear plant beginning commercial operation in the United States was twice as expensive (in constant dollars) from 1981 to 1984 as it was from 1977 to 1980.

Construction Time

Although plant size also increased, the average time to construct a U.S. nuclear plant went from about 5 years prior to 1975 to about 12 years from 1985 to 1989. U.S. construction times are much longer than those in other major nuclear countries, except for the United Kingdom. Over the period 1978 to 1989, the U.S. average construction time was nearly twice that of France and more than twice that of Japan.

Billions of dollars in disallowances of recovery of costs from utility ratepayers have made utilities and the financial community leery of further investments in nuclear power plants. During the 1980s, rate base disallowances by state regulators totaled about $14 billion for nuclear plants, but only about $0.7 billion for non-nuclear plants.

Operation and maintenance (O&M) costs for U.S. nuclear plants have increased faster than for coal plants. Over the decade of the 1980s, U.S. nuclear O&M-plus-fuel costs grew from nearly half to about the same as those for fossil fueled plants, a significant shift in relative advantage.

Performance

On average, U.S. nuclear plants have poorer capacity factors compared to those of plants in other Organization for Economic Cooperation and Development (OECD) countries. On a lifetime basis, the United States is barely above 60 percent capacity factor, while France and Japan are at 68 percent, and West Germany is at 74 percent. Moreover, through 1988 12 U.S. plants were in the bottom 22. However, some U.S. plants do very well: 3 of the top 22 OECD plants through 1988 were U.S. U.S. plants averaged 65 percent in 1988, 63 percent in 1989, and 68 percent in 1990.

Except for capacity factors, the performance indicators of U.S. nuclear plants have improved significantly over the past several years. If the industry is to achieve parity with the operating performance in other countries, it must carefully examine its failure to achieve its own goal in this area and develop improved strategies, including better management practices. Such practices are important if the generators are to develop confidence that the new generation of plants can achieve the higher load factors estimated by the vendors.

Public Attitudes

There has been substantial opposition to new plants. The failure to solve the high-level radioactive waste disposal problem has harmed nuclear power's public image. It is the Committee's opinion, based upon our experience, that, more recently, an inability of states, that are members of regional compact commissions, to site low-level radioactive waste facilities has also harmed nuclear power's public image.

Several factors seem to influence the public to have a less than positive attitude toward new nuclear plants:

no perceived urgency for new capacity;

nuclear power is believed to be more costly than alternatives;

concerns that nuclear power is not safe enough;

little trust in government or industry advocates of nuclear power;

concerns about the health effects of low-level radiation;

concerns that there is no safe way to dispose of high-level waste; and

concerns about proliferation of nuclear weapons.

The Committee concludes that the following would improve public opinion of nuclear power:

a recognized need for a greater electrical supply that can best be met by large plants;

economic sanctions or public policies imposed to reduce fossil fuel burning;

maintaining the safe operation of existing nuclear plants and informing the public;

providing the opportunity for meaningful public participation in nuclear power issues, including generation planning, siting, and oversight;

better communication on the risk of low-level radiation;

resolving the high-level waste disposal issue; and

assurance that a revival of nuclear power would not increase proliferation of nuclear weapons.

As a result of operating experience, improved O&M training programs, safety research, better inspections, and productive use of probabilistic risk analysis, safety is continually improved. The Committee concludes that the risk to the health of the public from the operation of current reactors in the United States is very small. In this fundamental sense, current reactors are safe. However, a significant segment of the public has a different perception and also believes that the level of safety can and should be increased. The

development of advanced reactors is in part an attempt to respond to this public attitude.

Institutional Changes

The Committee believes that large-scale deployment of new nuclear power plants will require significant changes by both industry and government.

One of the most important factors affecting the future of nuclear power in the United States is its cost in relation to alternatives and the recovery of these capital and operating charges through rates that are charged for the electricity produced. Chapter 2 of this report deals with these issues in some detail. As stated there, the industry must develop better methods for managing the design and construction of nuclear plants. Arrangements among the participants that would assure timely, economical, and high-quality construction of new nuclear plants, the Committee believes, will be prerequisites to an adequate degree of assurance of capital cost recovery from state regulatory authorities in advance of construction. The development of state prudency laws also can provide a positive response to this issue.

The Committee and others are well aware of the increases in nuclear plant construction and operating costs over the last 20 years and the extension of plant construction schedules over this same period. 1 The Committee believes there are many reasons for these increases but is unable to disaggregate the cost effect among these reasons with any meaningful precision.

Like others, the Committee believes that the financial community and the generators must both be satisfied that significant improvements can be achieved before new plants can be ordered. In addition, the Committee believes that greater confidence in the control of costs can be realized with plant designs that are more nearly complete before construction begins, plants that are easier to construct, use of better construction and management methods, and business arrangements among the participants that provide stronger incentives for cost-effective, timely completion of projects.

It is the Committee's opinion, based upon our experience, that the principal participants in the nuclear industry--utilities, architect-engineers, and suppliers –should begin now to work out the full range of contractual arrangements for advanced nuclear power plants. Such arrangements would

increase the confidence of state regulatory bodies and others that the principal participants in advanced nuclear power plant projects will be financially accountable for the quality, timeliness, and economy of their products and services.

Inadequate management practices have been identified at some U.S. utilities, large and small public and private. Because of the high visibility of nuclear power and the responsibility for public safety, a consistently higher level of demonstrated utility management practices is essential before the U.S. public's attitude about nuclear power is likely to improve.

Over the past decade, utilities have steadily strengthened their ability to be responsible for the safety of their plants. Their actions include the formation and support of industry institutions, including the Institute of Nuclear Power Operations (INPO). Self-assessment and peer oversight through INPO are acknowledged to be strong and effective means of improving the performance of U.S. nuclear power plants. The Committee believes that such industry self-improvement, accountability, and self-regulation efforts improve the ability to retain nuclear power as an option for meeting U.S. electric energy requirements. The Committee encourages industry efforts to reduce reliance on the adversarial approach to issue resolution.

It is the Committee's opinion, based upon our experience, that the nuclear industry should continue to take the initiative to bring the standards of every American nuclear plant up to those of the best plants in the United States and the world. Chronic poor performers should be identified publicly and should face the threat of insurance cancellations. Every U.S. nuclear utility should continue its full-fledged participation in INPO; any new operators should be required to become members through insurance prerequisites or other institutional mechanisms.

Standardization. The Committee views a high degree of standardization as very important for the retention of nuclear power as an option for meeting U.S. electric energy requirements. There is not a uniformly accepted definition of standardization. The industry, under the auspices of the Nuclear Power Oversight Committee, has developed a position paper on standardization that provides definitions of the various phases of standardization and expresses an industry commitment to standardization. The Committee believes that a strong and sustained commitment by the principal participants will be required to realize the potential benefits of standardization (of families of plants) in the diverse U.S. economy. It is the Committee's opinion, based upon our experience, that the following will be necessary:

Families of standardized plants will be important for ensuring the highest levels of safety and for realizing the potential economic benefits of new nuclear plants. Families of standardized plants will allow standardized approaches to plant modification, maintenance, operation, and training.

Customers, whether utilities or other entities, must insist on standardization before an order is placed, during construction, and throughout the life of the plant.

Suppliers must take standardization into account early in planning and marketing. Any supplier of standardized units will need the experience and resources for a long-term commitment.

Antitrust considerations will have to be properly taken into account to develop standardized plants.

Nuclear Regulatory Commission

An obstacle to continued nuclear power development has been the uncertainties in the Nuclear Regulatory Commission's (NRC) licensing process. Because the current regulatory framework was mainly intended for light water reactors (LWR) with active safety systems and because regulatory standards were developed piecemeal over many years, without review and consolidation, the regulations should be critically reviewed and modified (or replaced with a more coherent body of regulations) for advanced reactors of other types. The Committee recommends that NRC comprehensively review its regulations to prepare for advance reactors, in particular. LWRs with passive safety features. The review should proceed from first principles to develop a coherent, consistent set of regulations.

The Committee concludes that NRC should improve the quality of its regulation of existing and future nuclear power plants, including tighter management controls over all of its interactions with licensees and consistency of regional activities. Industry has proposed such to NRC.

The Committee encourages efforts by NRC to reduce reliance on the adversarial approach to issue resolution. The Committee recommends that NRC encourage industry self-improvement, accountability, and self-regulation initia tives . While federal regulation plays an important safety role, it must not be allowed to detract from or undermine the accountability of utilities and their line management organizations for the safety of their plants.

It is the Committee's expectation that economic incentive programs instituted by state regulatory bodies will continue for nuclear power plant operators. Properly formulated and administered, these programs should improve the economic performance of nuclear plants, and they may also enhance safety. However, they do have the potential to provide incentives counter to safety. The Committee believes that such programs should focus

on economic incentives and avoid incentives that can directly affect plant safety. On July 18, 1991 NRC issued a Nuclear Regulatory Commission Policy Statement which expressed concern that such incentive programs may adversely affect safety and commits NRC to monitoring such programs. A joint industry/state study of economic incentive programs could help assure that such programs do not interfere with the safe operation of nuclear power plants.

It is the Committee's opinion, based upon our experience, that NRC should continue to exercise its federally mandated preemptive authority over the regulation of commercial nuclear power plant safety if the activities of state government agencies (or other public or private agencies) run counter to nuclear safety. Such activities would include those that individually or in the aggregate interfere with the ability of the organization with direct responsibility for nuclear plant safety (the organization licensed by the Commission to operate the plant) to meet this responsibility. The Committee urges close industry-state cooperation in the safety area.

It is also the Committee's opinion, based upon our experience, that the industry must have confidence in the stability of NRC's licensing process. Suppliers and utilities need assurance that licensing has become and will remain a manageable process that appropriately limits the late introduction of new issues.

It is likely that, if the possibility of a second hearing before a nuclear plant can be authorized to operate is to be reduced or eliminated, legislation will be necessary. The nuclear industry is convinced that such legislation will be required to increase utility and investor confidence to retain nuclear power as an option for meeting U.S. electric energy requirements. The Committee concurs.

It is the Committee's opinion, based upon our experience, that potential nuclear power plant sponsors must not face large unanticipated cost increases as a result of mid-course regulatory changes, such as backfits. NRC 's new licensing rule, 10 CFR Part 52, provides needed incentives for standardized designs.

Industry and the Nuclear Regulatory Commission

The U.S. system of nuclear regulation is inherently adversarial, but mitigation of unnecessary tension in the relations between NRC and its nuclear power licensees would, in the Committee's opinion, improve the regulatory environment and enhance public health and safety. Thus, the Committee commends the efforts by both NRC and the industry to work

more cooperatively together and encourages both to continue and strengthen these efforts.

Department of Energy

Lack of resolution of the high-level waste problem jeopardizes future nuclear power development. The Committee believes that the legal status of the Yucca Mountain site for a geologic repository should be resolved soon, and that the Department of Energy's (DOE) program to investigate this site should be continued. In addition, a contingency plan must be developed to store high-level radioactive waste in surface storage facilities pending the availability of the geologic repository.

Environmental Protection Agency

The problems associated with establishing a high-level waste site at Yucca Mountain are exacerbated by the requirement that, before operation of a repository begins, DOE must demonstrate to NRC that the repository will perform to standards established by the Environmental Protection Agency (EPA). NRC's staff has strongly questioned the workability of these quantitative requirements, as have the National Research Council's Radioactive Waste Management Board and others. The Committee concludes that the EPA standard for disposal of high-level waste will have to be reevaluated to ensure that a standard that is both adequate and feasible is applied to the geologic waste repository.

Administration and Congress

The Price-Anderson Act will expire in 2002. The Committee sought to discover whether or not such protection would be required for advanced reactors. The clear impression the Committee received from industry representatives was that some such protection would continue to be needed, although some Committee members believe that this was an expression of desire rather than of need. At the very least, renewal of Price-Anderson in 2002 would be viewed by the industry as a supportive action by Congress and would eliminate the potential disruptive effect of developing alternative liability arrangements with the insurance industry. Failure to renew Price-Anderson in 2002 would raise a new impediment to nuclear power plant orders as well as possibly reduce an assured source of funds to accident victims.

The Committee believes that the National Transportation Safety Board (NTSB) approach to safety investigations, as a substitute for the present NRC approach, has merit. In view of the infrequent nature of the activities of such a committee, it may be feasible for it to be established on an ad hoc basis and report directly to the NRC chairman. Therefore, the Committee recommends that such a small safety review entity be established. Before the establishment of such an activity, its charter should be carefully defined, along with a clear delineation of the classes of accidents it would investigate. Its location in the government and its reporting channels should also be specified. The function of this group would parallel those of NTSB. Specifically, the group would conduct independent public investigations of serious incidents and accidents at nuclear power plants and would publish reports evaluating the causes of these events. This group would have only a small administrative structure and would bring in independent experts, including those from both industry and government, to conduct its investigations.

It is the Committee's opinion, based upon our experience, that responsible arrangements must be negotiated between sponsors and economic regulators to provide reasonable assurances of complete cost recovery for nuclear power plant sponsors. Without such assurances, private investment capital is not likely to flow to this technology.

In Chapter 2 , the Committee addressed the non-recovery of utility costs in rate proceedings and concluded that better methods of dealing with this issue must be established. The Committee was impressed with proposals for periodic reviews of construction progress and costs--“rolling prudency” determinations--as one method for managing the risks of cost recovery. The Committee believes that enactment of such legislation could remove much of the investor risk and uncertainty currently associated with state regulatory treatment of new power plant construction, and could therefore help retain nuclear power as an option for meeting U.S. electric energy requirements.

On balance, however, unless many states adopt this or similar legislation, it is the Committee's view that substantial assurances probably cannot be given, especially in advance of plant construction, that all costs incurred in building nuclear plants will be allowed into rate bases.

The Committee notes the current trend toward economic deregulation of electric power generation. It is presently unclear whether this trend is compatible with substantial additions of large-scale, utility-owned, baseload generating capacity, and with nuclear power plants in particular.

It is the Committee's opinion, based upon our experience, that regional low-level radioactive waste compact commissions must continue to establish disposal sites.

The institutional challenges are clearly substantial. If they are to be met, the Committee believes that the Federal government must decide, as a matter of national policy, whether a strong and growing nuclear power program is vital to the economic, environmental, and strategic interests of the American people. Only with such a clearly stated policy, enunciated by the President and backed by the Congress through appropriate statutory changes and appropriations, will it be possible to effect the institutional changes necessary to return the flow of capital and human resources required to properly employ this technology.

Alternative Reactor Technologies

Advanced reactors are now in design or development. They are being designed to be simpler, and, if design goals are realized, these plants will be safer than existing reactors. The design requirements for the advanced reactors are more stringent than the NRC safety goal policy. If final safety designs of advanced reactors, and especially those with passive safety features, are as indicated to this Committee, an attractive feature of them should be the significant reduction in system complexity and corresponding improvement in operability. While difficult to quantify, the benefit of improvements in the operator 's ability to monitor the plant and respond to system degradations may well equal or exceed that of other proposed safety improvements.

The reactor concepts assessed by the Committee were the large evolutionary LWRs, the mid-sized LWRs with passive safety features, 2 the Canadian deuterium uranium (CANDU) heavy water reactor, the modular high-temperature gas-cooled reactor (MHTGR), the safe integral reactor (SIR), the process inherent ultimate safety (PIUS) reactor, and the liquid metal reactor (LMR). The Committee developed the following criteria for comparing these reactor concepts:

safety in operation;

economy of construction and operation;

suitability for future deployment in the U.S. market;

fuel cycle and environmental considerations;

safeguards for resistance to diversion and sabotage;

technology risk and development schedule; and

amenability to efficient and predictable licensing.

With regard to advanced designs, the Committee reached the following conclusions.

Large Evolutionary Light Water Reactors

The large evolutionary LWRs offer the most mature technology. The first standardized design to be certified in the United States is likely to be an evolutionary LWR. The Committee sees no need for federal research and development (R&D) funding for these concepts, although federal funding could accelerate the certification process.

Mid-sized Light Water Reactors with Passive Safety Features

The mid-sized LWRs with passive safety features are designed to be simpler, with modular construction to reduce construction times and costs, and to improve operations. They are likely the next to be certified.

Because there is no experience in building such plants, cost projections for the first plant are clearly uncertain. To reduce the economic uncertainties it will be necessary to demonstrate the construction technology and improved operating performance. These reactors differ from current reactors in construction approach, plant configuration, and safety features. These differences do not appear so great as to require that a first plant be built for NRC certification. While a prototype in the traditional sense will not be required, the Committee concludes that no first-plant mid-sized LWR with passive safety features is likely to be certified and built without government incentives, in the form of shared funding or financial guarantees.

CANDU Heavy Water Reactor

The Committee judges that the CANDU ranks below the advanced mid-sized LWRs in market potential. The CANDU-3 reactor is farther along in design than the mid-sized LWRs with passive safety features. However, it has not entered NRC's design certification process. Commission requirements are complex and different from those in Canada so that U.S. certification

could be a lengthy process. However, the CANDU reactor can probably be licensed in this century.

The heavy water reactor is a mature design, and Canadian entry into the U.S. marketplace would give added insurance of adequate nuclear capacity if it is needed in the future. But the CANDU does not offer advantages sufficient to justify U.S. government assistance to initiate and conduct its licensing review.

Modular High-Temperature Gas-Cooled Reactor

The MHTGR posed a difficult set of questions for the Committee. U.S. and foreign experience with commercial gas-cooled reactors has not been good. A consortium of industry and utility people continue to promote federal funding and to express interest in the concept, while none has committed to an order.

The reactor, as presently configured, is located below ground level and does not have a conventional containment. The basic rationale of the designers is that a containment is not needed because of the safety features inherent in the properties of the fuel.

However, the Committee was not convinced by the presentations that the core damage frequency for the MHTGR has been demonstrated to be low enough to make a containment structure unnecessary. The Oak Ridge National Laboratory estimates that data to confirm fuel performance will not be available before 1994. The Committee believes that reliance on the defense-in-depth concept must be retained, and accurate evaluation of safety will require evaluation of a detailed design.

A demonstration plant for the MHTGR could be licensed slightly after the turn of the century, with certification following demonstration of successful operation. The MHTGR needs an extensive R&D program to achieve commercial readiness in the early part of the next century. The construction and operation of a first plant would likely be required before design certification. Recognizing the opposite conclusion of the MHTGR proponents, the Committee was not convinced that a foreseeable commercial market exists for MHTGR-produced process heat, which is the unique strategic capability of the MHTGR. Based on the Committee 's view on containment requirements, and the economics and technology issues, the Committee judged the market potential for the MHTGR to be low.

The Committee believes that no funds should be allocated for development of high-temperature gas-cooled reactor technology within the commercial nuclear power development budget of DOE.

Safe Integral Reactor and Process Inherent Ultimate Safety Reactor

The other advanced light water designs the Committee examined were the United Kingdom and U.S. SIR and the Swedish PIUS reactor.

The Committee believes there is no near-term U.S. market for SIR and PIUS. The development risks for SIR and PIUS are greater than for the other LWRs and CANDU-3. The lack of operational and regulatory experience for these two is expected to significantly delay their acceptance by utilities. SIR and PIUS need much R&D, and a first plant will probably be required before design certification is approved.

The Committee concluded that no Federal funds should be allocated for R&D on SIR or PIUS.

Liquid Metal Reactor

LMRs offer advantages because of their potential ability to provide a long-term energy supply through a nearly complete use of uranium resources. Were the nuclear option to be chosen, and large scale deployment follow, at some point uranium supplies at competitive prices might be exhausted. Breeder reactors offer the possibility of extending fissionable fuel supplies well past the next century. In addition, actinides, including those from LWR spent fuel, can undergo fission without significantly affecting performance of an advanced LMR, transmuting the actinides to fission products, most of which, except for technetium, carbon, and some others of little import, have half-lives very much shorter than the actinides. (Actinides are among the materials of greatest concern in nuclear waste disposal beyond about 300 years.) However, substantial further research is required to establish (1) the technical and the economic feasibility of recycling in LMRs actinides recovered from LWR spent fuel, and (2) whether high-recovery recycling of transuranics and their transmutation can, in fact, benefit waste disposal. Assuming success, it would still be necessary to dispose of high-level waste, although the waste would largely consist of significantly shorter-lived fission products. Special attention will be necessary to ensure that the LMR's reprocessing facilities are not vulnerable to sabotage or to theft of plutonium.

The unique property of the LMR, fuel breeding, might lead to a U.S. market, but only in the long term. From the viewpoint of commercial licensing, it is far behind the evolutionary and mid-sized LWRs with passive safety features in having a commercial design available for review. A federally funded program, including one or more first plants, will be required before any LMR concept would be accepted by U.S. utilities.

Net Assessment

The Committee could not make any meaningful quantitative comparison of the relative safety of the various advanced reactor designs. The Committee believes that each of the concepts considered can be designed and operated to meet or closely approach the safety objectives currently proposed for future, advanced LWRs. The different advanced reactor designs employ different mixes of active and passive safety features. The Committee believes that there currently is no single optimal approach to improved safety. Dependence on passive safety features does not, of itself, ensure greater safety. The Committee believes that a prudent design course retains the historical defense-in-depth approach.

The economic projections are highly uncertain, first, because past experience suggests higher costs, longer construction times, and lower availabilities than projected and, second, because of different assumptions and levels of maturity among the designs. The Electric Power Research Institute (EPRI) data, which the Committee believes to be more reliable than that of the vendors, indicate that the large evolutionary LWRs are likely to be the least costly to build and operate on a cost per kilowatt electric or kilowatt hour basis, while the high-temperature gas-cooled reactors and LMRs are likely to be the most expensive. EPRI puts the mid-sized LWRs with passive safety features between the two extremes.

Although there are definite differences in the fuel cycle characteristics of the advanced reactors, fuel cycle considerations did not offer much in the way of discrimination among reactors, nor did safeguards and security considerations, particularly for deployment in the United States. However, the CANDU (with on-line refueling and heavy water) and the LMR (with reprocessing) will require special attention to safeguards.

SIR, MHTGR, PIUS, and LMR are not likely to be deployed for commercial use in the United States, at least within the next 20 years. The development required for commercialization of any of these concepts is substantial.

It is the Committee's overall assessment that the large evolutionary LWRs and the mid-sized LWRs with passive safety features rank highest relative to the Committee 's evaluation criteria. The evolutionary reactors could be ready for deployment by 2000, and the mid-sized could be ready for initial plant construction soon after 2000. The Committee's evaluations and overall assessment are summarized in Figure 5-1 .

FIGURE 5.1 Assessment of advanced reactor technologies.

This table is an attempt to summarize the Committee's qualitative rankings of selected reactor types against each other , without reference either to an absolute standard or to the performance of any other energy resource options, This evaluation was based on the Committee's professional judgment.

The Committee has concluded the following:

Safety and cost are the most important characteristics for future nuclear power plants.

LWRs of the large evolutionary and the mid-sized advanced designs offer the best potential for competitive costs (in that order).

Safety benefits among all reactor types appear to be about equal at this stage in the design process. Safety must be achieved by attention to all failure modes and levels of design by a multiplicity of safety barriers and features. Consequently, in the absence of detailed engineering design and because of the lack of construction and operating experience with the actual concepts, vendor claims of safety superiority among conceptual designs cannot be substantiated.

LWRs can be deployed to meet electricity production needs for the first quarter of the next century:

The evolutionary LWRs are further developed and, because of international projects, are most complete in design. They are likely to be the first plants certified by NRC. They are expected to be the first of the advanced reactors available for commercial use and could operate in the 2000 to 2005 time frame. Compared to current reactors, significant improvements in safety appear likely. Compared to recently completed high-cost reactors, significant improvements also appear possible in cost if institutional barriers are resolved. While little or no federal funding is deemed necessary to complete the process, such funding could accelerate the process.

Because of the large size and capital investment of evolutionary reactors, utilities that might order nuclear plants may be reluctant to do so. If nuclear power plants are to be available to a broader range of potential U.S. generators, the development of the mid-sized plants with passive safety features is important. These reactors are progressing in their designs, through DOE and industry funding, toward certification in the 1995 to 2000 time frame. The Committee believes such funding will be necessary to complete the process. While a prototype in the traditional sense will not be required, federal funding will likely be required for the first mid-sized LWR with passive safety features to be ordered.

Government incentives, in the form of shared funding or financial guarantees, would likely accelerate the next order for a light water plant. The Committee has not addressed what type of government assistance should be provided nor whether the first advanced light water plant should be a large evolutionary LWR or a mid-sized passive LWR.

The CANDU-3 reactor is relatively advanced in design but represents technology that has not been licensed in the United States. The Committee did not find compelling reasons for federal funding to the vendor to support the licensing.

SIR and PIUS, while offering potentially attractive safety features, are unlikely to be ready for commercial use until after 2010. This alone may limit their market potential. Funding priority for research on these reactor systems is considered by the Committee to be low.

MHTGRs also offer potential safety features and possible process heat applications that could be attractive in the market place. However, based on the extensive experience base with light water technology in the United States, the lack of success with commercial use of gas technology, the likely higher costs of this technology compared with the alternatives, and the substantial development costs that are still required before certification, 3 the Committee concluded that the MHTGR had a low market potential. The Committee considered the possibility that the MHTGR might be selected as the new tritium production reactor for defense purposes and noted the vendor association's estimated reduction in development costs for a commercial version of the MHTGR. However, the Committee concluded, for the reasons summarized above, that the commercial MHTGR should be given low priority for federal funding.

LMR technology also provides enhanced safety features, but its uniqueness lies in the potential for extending fuel resources through breeding. While the market potential is low in the near term (before the second quarter of the next century), it could be an important long-term technology, especially if it can be demonstrated to be economic. The Committee believes that the LMR should have the highest priority for long-term nuclear technology development.

The problems of proliferation and physical security posed by the various technologies are different and require continued attention. Special attention will need to be paid to the LMR.

Alternative Research and Development Programs

The Committee developed three alternative R&D programs, each of which contains three common research elements: (1) reactor research using federal facilities. The experimental breeder reactor-II, hot fuel examination facility/south, and fuel manufacturing facility are retained for the LMR; (2) university research programs; and (3) improved performance and life extension programs for existing U.S. nuclear power plants.

The Committee concluded that federal support for development of a commercial version of the MHTGR should be a low priority. However, the fundamental design strategy of the MHTGR is based upon the integrity of the fuel (=1600°C) under operation and accident conditions. There are other potentially significant uses for such fuel, in particular, space propulsion. Consequently, the Committee believes that DOE should consider maintaining a coated fuel particle research program within that part of DOE focused on space reactors.

Alternative 1 adds funding to assist development of the mid-sized LWRs with passive safety features. Alternative 2 adds a LMR development program and associated facilities--the transient reactor test facility, the zero power physics reactor, the Energy Technology Engineering Center, and either the hot fuel examination facility/north in Idaho or the Hanford hot fuel examination facility. This alternative would also include limited research to examine the feasibility of recycling actinides from LWR spent fuel, utilizing the LMR. Finally, Alternative 3 adds the fast flux test facility and increases LMR funding to accelerate reactor and integral fast reactor fuel cycle development and examination of actinide recycle of LWR spent fuel.

None of the three alternatives contain funding for development of the MHTGR, SIR, PIUS, or CANDU-3.

Significant analysis and research is required to assess both the technical and economic feasibility of recycling actinides from LWR spent fuel. The Committee notes that a study of separations technology and transmutation systems was initiated in 1991 by DOE through the National Research Council's Board on Radioactive Waste Management.

It is the Committee's judgment that Alternative 2 should be followed because it:

provides adequate support for the most promising near-term reactor technologies;

provides sufficient support for LMR development to maintain the technical capabilities of the LMR R&D community;

would support deployment of LMRs to breed fuel by the second quarter of the next century should that be needed; and

would maintain a research program in support of both existing and advanced reactors.

The construction of nuclear power plants in the United States is stopping, as regulators, reactor manufacturers, and operators sort out a host of technical and institutional problems.

This volume summarizes the status of nuclear power, analyzes the obstacles to resumption of construction of nuclear plants, and describes and evaluates the technological alternatives for safer, more economical reactors. Topics covered include:

• Institutional issues—including regulatory practices at the federal and state levels, the growing trends toward greater competition in the generation of electricity, and nuclear and nonnuclear generation options.
• Critical evaluation of advanced reactors—covering attributes such as cost, construction time, safety, development status, and fuel cycles.

Finally, three alternative federal research and development programs are presented.

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77 Nuclear Power Essay Topics & Examples

If you’re looking for nuclear power essay topics, you may be willing to discuss renewable energy sources, sustainable development, and climate change as well. With the paper titles collected by our team , you’ll be able to explore all these issues!

🏆 Best Nuclear Energy Essay Topics & Examples

👍 good nuclear energy research paper topics, ❓ questions about nuclear power.

• Pros and Cons of Nuclear Power The first pro of nuclear energy is that it emits little pollution to the environment. The next con of nuclear energy is the occurrence of a meltdown.
• Why Nuclear Energy Is Not Good? Even those who say net production is cost effective for unit of nuclear energy produced may not be saying the truth because most of these estimate forget that nuclear energy is recipient of many government […]
• Nuclear Power in India The demand for electricity in India is increasing and there is a need to increase the level of supply to meet the demand and the best option is to invest more in nuclear power, considering […]
• Nuclear Energy Effectiveness Although water is used to cool nuclear plants, we can conclude that nuclear energy is the most cost effective method of producing electricity.
• The Nuclear Power Passages: Rhetorical Analysis At that, the writer also provides some data utilized by the former vice president and some information to show the negative side of power plants.
• Nuclear Power Advantages and Disadvantages The claim is thought to include cost of installations and time taken to construct the nuclear plants. In this case, they fail to note that the cost of electricity from nuclear energy is cheaper than […]
• Nuclear Power Provides Cheap and Clean Energy The production of nuclear power is relatively cheap when compared to coal and petroleum. The cost of nuclear fuel for nuclear power generation is much lower compared to coal, oil and gas fired plants.
• Sustainable Energy Source – Nuclear Energy One of the groups led by World Nuclear Association, believes that nuclear energy is a reliable and efficient source of energy.
• Combined-Cycle Gas Plant: The Nuclear Power Plant Replacement This essay will make the case for the use of a combined-cycle gas plant as the best option for replacing a state’s nuclear power plant, as well as explain why a carbon tax or cap-and-trade […]
• Metropolitan Edison Company vs. People Against Nuclear Energy In addition, the commission published a hearing notice which entailed an invitation to parties that were interested to submit their briefs explaining the impacts of the accident to the psychological harm or any other indirect […]
• Biological Effect of Man-Made Disasters in Nuclear Power Plants When it is disrupted in the reproductive organs, the changes are passed on to the offspring as mutations, which are mostly harmful to the organism and related to many deaths in the course of the […]
• Nuclear Energy: High-Entropy Alloy One of the tools for reducing the level of greenhouse gas emissions is the development of nuclear energy, which is characterized by a high degree of environmental efficiency and the absence of a significant impact […]
• Tsunami Handling at a Nuclear Power Plant The information presented in this research paper has been analyzed and proved to be the actual content obtained by various parties that participate in the study of tsunamis.
• Nuclear Energy: Impact of Science & Technology on Society In spite of the fact that hopes of adherents of the use of atomic energy substantially were not justified, the majority of the governments of the countries of the world do not wish to refuse […]
• Nuclear Energy and The Danger of Environment Nuclear energy can be a benefit in the medium and long term perspective, but the communal and public awareness of nuclear energy breeds anxieties about nuclear technology that must be directed to attain the public […]
• Nuclear Power Plants’ Safety Strategy Implementation Thus, incidents that occur on nuclear power plants are critical and pose a significant risk to the life and health of workers.
• Nuclear Power: Is It Sustainable? Another controversial aspect of nuclear power is its effects on human health and the environment. Finally, the use of nuclear energy is a significant political and ethical concern.
• Iranian Public Opinion on Nuclear Power and Economy Other research topics included the Israel-Palestine conflict, the war in Iraq, the Iranian system of government, and Iran’s relation to the US and the West.
• Nuclear Energy: Safe, Economical, Reliable Thus, nuclear energy is viable and safe in meeting the current and future demand for energy across the world. Nuclear energy has significant implications for the environment and population health in case of an accident […]
• Nuclear Power Plant’s Life Cycle Costing Drivers As such, the article offers an in-depth discussion on the need for effective management of the life cycle of a nuclear power plant.
• Emirates Nuclear Energy Corporation: Business Principles The first 3 are enablers of the system of management while the fourth component is process-oriented, which helps in the development, production, and delivery of services coupled with products of an organization to the market […]
• Nuclear Power as a Primary Energy Source The energy crisis the world faces currently is one of the most urgent and disturbing questions countries have to deal with.
• Nuclear Energy and Its Risks The situation became difficult when the power in the reactors reduced and could not be enough to be used by the operators.
• Nuclear Power & Environment The use of nuclear energy is one of the issues that are debated by environmental scientists, economists as well as engineers.
• Nuclear Power Exploitation to Generate Electricity Nuclear power plants expose the society to significant dangers in the event of a major disaster in the nuclear power plant.
• Fossil Fuel, Nuclear Energy, and Alternative Power Sources It is important to keep in mind that the amount of coal is decreasing and there is no guarantee that people will be able to discover more.
• Emirates Nuclear Energy Corporation’s Employee Training Program The problem is the need to incorporate training and development as part of the human resource management policies of the Emirates Nuclear Energy Corporation.
• Nuclear Power Station Advantages and Disadvantages The use of nuclear power to produce electricity increases the energy dependence of a country. It has demonstrated that nuclear power is capable of producing enough electricity to satisfy the growing global energy demands.
• Harmful Health Effects of Nuclear Energy The risk of developing thyroid cancer following exposure to nuclear radiations increased with a decrease in the age of the subject.
• Nuclear Power — Mega Trend The developmental milestone of the discovery of nuclear fission in the early 30’s paved way to the advent of nuclear power as a source of energy.
• Nuclear Power Use Controversies As a result, a person in the industrial world needs to have a wide knowledge of its environment. For example, technological adaptation is tied to interest of the public and the government.
• The Chronicle of North Korea’s Nuclear Power and Diplomacy Lastly, the paper analyzes the Six-Party talk in terms of its successes and failures with special focus on the current status of the nuclear development program in North Korea.
• A Cost Benefit Analysis of the Environmental and Economic Effects of Nuclear Energy in the United States The nature of damage posed to the environment depends on the nature of the nuclear plant being used and also the extraction process of fossil fuel themselves.
• Nuclear Energy Fusion and Harnessing Physicists use the equation E=MC2 to calculate the amount of energy that is generated as a result of the fusion of nucleus.
• Nuclear Energy Usage and Recycling The resulting energy is used to power machinery and generate heat for processing purposes. The biggest problem though is that of energy storage, which is considered to be the most crucial requirement for building a […]
• The Effect of Nuclear Energy on the Environment In response to the concerns, this paper proposes the use of thorium reactors to produce nuclear energy because the safety issues of uranium.
• The Emirates Nuclear Energy Corporation The Emirates Nuclear Energy Corporation, ENEC, brought together six UAE member states, the International Atomic Energy Agency and other countries such as the United States of America. The assertions made above indicate that UAE relies […]
• Nuclear Power Crisis in Japan and Its Implications Nuclear power is perceived in Indonesia, Vietnam, and Thailand and perhaps somewhere else in Asia as an ingredient in a resolution aimed at achieving the requirement of an exceptionally huge amplification of power manufacturing capacity […]
• Nuclear Energy Benefits and Demerits The aim of the research is to provide substantial proof that nuclear energy is not efficient and sustainable. It is also argued that the whole process and the impacts of nuclear energy production make the […]
• Balanced Treatment of the Pros and Cons of Nuclear Energy Thus, the use of nuclear power presupposes a number of positive short-term and log-term consequences for the economy of the country and the environment of the planet.
• Nuclear Power and Its Effects on Economy, Environment and Safety Of all these, the nuclear power is the latest, realized in the dawn of the 20th century following the discovery some crucial radioactive elements and reactions like uranium and nuclear fission respectively, both of which […]
• The Environmental Impact of Nuclear Energy The country has the opportunity to enhance its capacity to generate electricity from nuclear following the approval of the US Nuclear Regulatory Commission to build and operate between three to four units of the Vogtle […]
• Should Production of Nuclear Power Be Stopped? A good example of a disaster caused by nuclear power accident is the accident in Chernobyl in April 1986, the accident was the worst in history and it led to mass displacement of people and […]
• Sources of Energy: Nuclear Power and Hydroelectric Power The main source of power in the world is the Sun. The Sun is the sole source of energy that plants use in the process of photosynthesis in order to manufacture their food.
• Nuclear Power’ Two Opposing Sides Thus, should possession of nuclear weapons be based on the desired end as to justify the means? It is acceptable to purport that nuclear power may be used if such is meant to promote peace […]
• Japan’s Nuclear Disaster: Fukushima’s Legacy The cladding, the reactor vessel, the containment building, and a dry-wall building were the barriers to protect the nuclear power plant.
• Dangers of Nuclear Power The external supply of power to the nuclear plant was disrupted by the earthquake. In addition, organization of the nuclear plant was responsible for some problems that were experienced.
• Why Developed Countries Should Not Produce Nuclear Power Though nuclear power generation is slowly gaining prominence in the world, especially since the world is seeking more sources of green energy, nuclear energy is a unique source of energy because it bears unique characteristics […]
• Nuclear Energy in Australia The irony of the matter is that Australia does not use these reserves to produce nuclear energy; two main reasons that has contributed to the un-exploitation are availability of rich coal deposits in the country, […]
• Impact of Nuclear Energy in France Through the process, heat energy is released from the bombardment of the nucleus and the neutrons. The need to manage the nuclear waste affected the economic parameters attached to nuclear energy.
• Nuclear Energy Benefits One of the factors why nuclear energy is an effective source of energy is that it is cost effective. The other factor that makes nuclear energy cost effective is that the risks associated with this […]
• Living With Chernobyl – The Future of Nuclear Power: Summary In the documentary, journalist Cliff Orloff and Olga Shalygin made the journey to the affected zone with the aim of establishing the truth of the predictions made.
• What Is Nuclear Power in Simple Terms?
• What Is the Main Purpose of Nuclear Energy?
• What Is a Nuclear Power Plant and How Does It Work?
• How Many Countries Use Nuclear Power?
• What Happens When a Nuclear Power Plant Is Hit?
• Why Should Nuclear Power Plants Be Closed?
• Where Is Nuclear Energy Used?
• Why Is Management of Nuclear Energy Easier Said Than Done?
• Why Nuclear Power Is Hazardous for Both Humans and Nature?
• Why Are Megaprojects, Including Nuclear Power Plants, Implemented Over Budget and Late?
• Why Should Australia Master Nuclear Power?
• Why Did Some People Change Their Attitude Toward Nuclear Energy After the Fukushima Accident?
• Why Does Iran Need Nuclear Power?
• What Are the Implications of China as an Emerging Nuclear Power?
• What Are the Prospects for the Environmental Sciences of Nuclear Energy?
• What Role Can Nuclear Power Play in Mitigating Global Warming?
• What Are the Advantages and Disadvantages of a Nuclear Power Plant?
• What Is the Emirates Nuclear Energy Corporation Employee Training Program?
• What Does Nuclear Energy Require?
• What Are Transaction Costs in Regulation and Subcontracting at a Nuclear Power Plant?
• What Is the Value of Modular Nuclear Power Plants in the Finite Time Horizon of Decision Making??
• How Is Nuclear Energy Stored?
• What Is the Truth About Jaitapur Nuclear Power Plant?
• How Strong Is Nuclear Energy?
• Is Nuclear Cheaper Than Solar?
• Chicago (A-D)
• Chicago (N-B)

IvyPanda. (2024, February 29). 77 Nuclear Power Essay Topics & Examples. https://ivypanda.com/essays/topic/nuclear-power-essay-topics/

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IvyPanda . 2024. "77 Nuclear Power Essay Topics & Examples." February 29, 2024. https://ivypanda.com/essays/topic/nuclear-power-essay-topics/.

1. IvyPanda . "77 Nuclear Power Essay Topics & Examples." February 29, 2024. https://ivypanda.com/essays/topic/nuclear-power-essay-topics/.

Bibliography

IvyPanda . "77 Nuclear Power Essay Topics & Examples." February 29, 2024. https://ivypanda.com/essays/topic/nuclear-power-essay-topics/.

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Remove a code repository from this paper, mark the official implementation from paper authors, add a new evaluation result row, remove a task, add a method, remove a method, edit datasets, pressure balance and energy budget of the nuclear superbubble of ngc 3079.

5 Apr 2024  ·  Jiang-Tao Li , Wei Sun , Li Ji , Yang Yang · Edit social preview

Superbubbles in the nuclear region of galaxies could be produced by the AGN or nuclear starburst via different driving forces. We report analysis of the multi-wavelength data of the kpc-scale nuclear superbubble in NGC 3079, in order to probe the mechanisms driving the expansion of the superbubble. Based on the Chandra X-ray observations, we derive the hot gas thermal pressure inside the bubble, which is about one order of magnitude higher than that of the warm ionized gas traced by optical lines. We derive a [C II]-based star formation rate of ${\rm SFR}\sim1.3\rm~M_\odot~{\rm yr}^{-1}$ from the nuclear region using the SOFIA/FIFI-LS observation. This SFR infers a radiation pressure toward the bubble shells much lower than the thermal pressure of the gases. The VLA radio image infers a magnetic pressure at the northeast cap above the superbubble less than the thermal pressure of the hot gas enclosed in the bubble, but has a clearly larger extension. The magnetic field may thus still help to reconcile the expansion of the bubble. The observed thermal energy of the hot gas enclosed in the bubble requires an energy injection rate of $\gtrsim10^{42}\rm~ergs~s^{-1}$ within the bubble's dynamical age, which is probably larger than the power provided by the current nuclear starburst and the parsec-scale jet. If this is true, stronger past AGN activity may provide an alternative energy source to drive the observed bubble expansion.

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