FAQS

Nuclear energy is a type of energy that is produced from the splitting of of atoms, tiny particles that form the building blocks of everything in the universe. At the center of the atom is the nucleus containing even smaller particles called protons and neutrons. When these particles are split apart they release a tremendous amount of energy in the form of heat and radiation. This is what we call nuclear energy.

This process in which atoms are split is called fission. In commercial nuclear plants, uranium fuel is placed in a nuclear reactor and is struck with neutrons, causing them to fission and release massive amounts of energy in the form of heat which turns water into steam, spinning a turbine and making electricity.

You can find more information about nuclear energy here.

Nuclear energy is one of the most regulated industries and adheres to rigorous safety standards. Despite stigma from highly publicized accidents, nuclear energy is actually one of the safest forms of energy.

In 2021, a European Commission research center (JRC) report concluded there is no scientific evidence suggesting nuclear energy is any more harmful to people and nature than any other energy source, including wind and solar.

Due to engineering standards, nuclear plants are built and upgraded to withstand incredible forces of nature – with time and lessons from various plants, the plants have become more robust. Within the operating system multiple layers of redundancy are built in. On top of this, plants possess some of the best security systems and trained guards in the world. Highly trained operators maintain excellent technical ability through training every three weeks.

To read more about safety regarding accidents and waste read our sections below.

Nuclear is one of the most environmentally friendly sources of energy that we have.

Nuclear’s environmental benefits far outweigh any negative environmental impact it has but like all energy sources, the associated negative environmental impacts come from the mining of the fuel or the rare earth metals needed. In the race to decarbonize and transition away from fossil fuels, ALL clean energy sources will require an expansion of mining activities.

Uranium mining admittedly has a problematic past, with private companies taking advantage of little paid Navajo miners and failing to provide safe mining conditions. You can read more about the history of mining in the Southwest, largely for weapons, in our section, here.

There are three methods of extracting uranium from the earth— open pit, underground mining, and in situ leaching.

Both open pit and underground mining techniques of uranium produce mill tailings in the form of waste rock containing radioactive byproducts and heavy metals. If not properly managed or cleaned, the radioactive byproduct dust can cause air and water pollution, harming local ecosystems.

Although uncommon at uranium mine sites, if sulfide minerals are present in the rock and are exposed to water and oxygen, acid mine drainage can occur. When this happens, the contaminated water is a carrier for toxic heavy metals and pollutes surrounding aquifers, surface water, and soil.

Open Pit: a mining process extracting rock or minerals from the earth through an open pit.

When uranium ore deposits are close to the surface, miners use the open pit surface mining technique, a process that strips away the topsoil and rock, above the uranium, digging a large hole, to extract and access the ore.

This process alters the landscape and disturbs the local ecosystem, fragmenting the habitat and causing the local wildlife to relocate or perish. The loss of flora and vegetation layer leads to greater erosion and produces large quantities of dust.

This process is the least expensive and most environmentally destructive form of uranium mining.

Underground: a mining process in which miners dig deep underground to drill and extract uranium to the surface.

When uranium ore deposits are hundreds to thousands of feet deep in the ground, miners build shafts and tunnels to access the ore where they drill and blast the rock, creating movable piles to the surface.

While underground mining has a smaller surface footprint and produces less waste rock than open pits, it is expensive and can lead to both surface and groundwater contamination.

Like all mineral mining exploration, the infrastructure needed to support the mining including roads, railways, or powerlines, impacts the environment.

In-Situ Leaching (ISL): a mining process that involves drilling holes into a uranium ore deposit located in porous rock and pumping an acid or base leaching solution into the cavities to dissolve uranium into an extractable solution.

ISL, the least invasive and intrusive form of uranium mining used today, requires only the drilling of injection and extraction wells, leaving little surface disturbance and no waste rock or tailings. The footprint of ISL is much lower than traditional mining since it does not require the large-scale excavation, hauling, and crushing of rock.

A small chance of local contamination of aquifers exists. However, contaminated water from the aquifer used for leaching is either evaporated or treated before reinjection. In the U.S., regulations require the water to be restored to its near original state where it can be used for the same purposes as pre-mining.

As of 2019, 57% of the world’s uranium mining came from ISL.

Read more about nuclear’s lifetime environmental impacts here.

A summary of why Nuclear is clean and sustainable can be found here.

Contrary to popular belief, nuclear waste is not green, liquid, or oozing, as the Simpsons imagined.

In fact, when people see actual images of the "waste" and are told about the management, most people are relieved and see the spent nuclear fuel (aka the “waste”) as actually rather boring.

The “waste” is not a technological but a societal problem. The fear and misconception around nuclear’s byproducts have been used as tool by anti-nuclear activists to mislead the public and scare communities since the 1970s.

But here are the four reasons why we think the nuclear waste debate has been misleading and careless, leading to undue fear.

• Nuclear is so energy dense that relative to the power produced, its waste is minimal.

• In fact, if nuclear energy powered your energy needs for your entire life, the waste produced would fit inside a Coke can.

• In the United States, all the “waste” produced by commercial nuclear generation since the 1950’s if stacked together, could fit on a football field with a depth of less than 10 yards.

• By contrast, a 1,000 MW coal station produces around 300,000 tonnes of coal ash and more than 6 million tonnes of carbon dioxide every year. Coal ash is one of the largest sources of industrial waste in the United States. This interactive map shows its proliferation across the United States and the danger it poses to the health of local communities.

• Nuclear energy is the ONLY energy-producing industry that must fully account for and manage its waste. This handling of its byproducts is included in the cost for every nuclear plant.

• Most spent nuclear fuel, what is generally referred to as nuclear waste, is safely stored, monitored, and surveilled on-site at power plants in steel canisters bolted into a large concrete pad -each metal cylinder is surrounded with an extra layer of steel and concrete designed to contain the heat aka radiation. The cans are built with a passive cooling system that allows for long-term use, up to 80 years, as the heat and radioactivity decrease over time.

• Nuclear waste, aka the spent fuel from a commercial nuclear plant, has NEVER hurt anyone!

• In the 65 years of commercial nuclear plants in the United States, the spent nuclear fuel has remained onsite and undisturbed. Additionally, the canisters have been engineered and designed to withstand the worst-case scenarios and maintain integrity against incredible forces like earthquakes, tornadoes, floods, and temperature extremes. In testing, they have even withstood high-speed trains and explosive weapons, including rocket-propelled grenades.

• Over 90% of its potential energy remains intact and can be reprocessed aka recycled.

• In reprocessing we are able to separate uranium from other fissile products to reduce the overall waste. Reprocessing sites exist in France, Japan, and Russia to be made into new fuel. Alternatively, certain spent fuel can be directly used and placed into CANDU nuclear reactors. This increases sustainability by reducing the need for mining.

In the 69 years of global commercial nuclear, there have been three well known nuclear accidents - Three Mile Island (1979), Chernobyl (1986), and Fukushima (2011). Although they garnered large media coverage and instilled widespread fear and panic, the expected health and environmental radiation health effects have largely not been realized. In fact, contrary to public belief, nuclear remains the safest form of energy, and after each accident, key lessons were learned, and modifications and updates were made to all nuclear plants.

To read more

Radiation is the release of energy in the form of waves or particles that travels through space and materials. Although you can't see, feel, or smell it, radiation is present all around us, including the sun, soil, and objects around us - it is a part of life.

Most radiation carries no risk to our health and is naturally present in our environment, but high levels of radiation exposure can cause harm and should be limited. Although nuclear fission produces high levels of radiation as a byproduct of the physical reaction, radiation and its effects are well understood and methods of safely containing it have been developed and in use for many years.

Each country determines their own radiation safety standards. In the U.S., radiation doses and exposure at nuclear plants are highly regulated in the U.S. by the Nuclear Regulatory Commission. Abroad, the International Atomic Energy Association (IAEA) works with countries across the globe to implement safety standards and manage radiation at nuclear plants.

Despite fears of radiation from nuclear plants, the public receives more doses of radiation from flying in an airplane, eating bananas, sun bathing, getting x-rays, or simply living in areas at high altitudes than living within 50 miles of a nuclear plant in a year. In fact, psychological impacts of fearing radiation have done more damage than any radiation exposure from commercial nuclear energy production.

Click here to explore the Radiation Dose Calculator, which shows comparative sources of radiation.

Click here to read more about nuclear radiation.

Yes!

It is important to remember that EVERY energy source has an impact on the environment, but nuclear is the most environmentally friendly clean energy source because it emits no greenhouse gasses, and has the smallest land footprint per unit of electricity produced and one of the lowest life cycle emissions.

Its land footprint is based on the life cycle assessment, meaning it does not only account for the land used by the energy plant itself but also the land use for the mining of materials for its construction, fuel inputs, decommissioning, and the handling of waste. Nuclear energy uses the least amount of land of ALL energy sources at O.3 meters squared per MWh.

Its life-cycle emissions include the total emissions from the building, maintaining, and decommissioning of an energy source. Nuclear life cycle emissions are roughly 1/1000 of coal power and lower than solar, wind, and hydropower.

Nuclear’s life cycle assessment is dominated by the nuclear fuel cycle rather than regular plant operation. The industry’s mining impact on the environment has been decreasing in recent decades as mining companies adopt in-situ leaching at higher levels.

In 2021, a European Commission research center (JRC) report concluded there is no scientific evidence suggesting nuclear energy is any more harmful to people and nature than any other energy source, including wind and solar.

In addition, over the last 50 years, Nuclear has prevented 70 gigatonnes of tons of C02, about 2 years worth of carbon emissions and continues to avoid more than 1 Gt CO2 annually.

Every year, nuclear energy prevents 470 million metric tons of C02 in emissions that would come from fossil fuels in the U.S., making it the largest source of clean energy.

Item In the past three years (with the energy crisis and wars in Palestine and Ukraine), unstable times combined with varying climate conditions have challenged and tested the world’s energy supply and demand. Such events have highlighted vulnerabilities, leading leaders and citizens to prioritize energy reliability and grid stability.

Comparing all current energy sources, nuclear plants have the highest capacity factor– the actual output of a plant compared to the maximum it can produce– of any energy source. In 2022, the global nuclear fleet had an average annual capacity factor of 82 percent.

In 2022, the United States nuclear plants performed with an average capacity factor of 92.7 percent, meaning they operated at full power 338 out of 365 days of the year. Despite fewer reactors in the U.S. since 2012, modifications to increase capacity have allowed the American nuclear fleet as a whole to maintain high capacity. Additionally, U.S. nuclear reactors possess the highest average monthly and annual capacity factors because they typically operate at or close to their generating capacity throughout the year in order to deliver firm, base-load electricity.

Unlike intermittent sources of generation, such as wind and solar that are determined by the availability of weather on a daily and seasonal basis, nuclear plants will have scheduled refueling outages every 12-24 months. However, these events of reduced generation are made in advance and are known by the grid operator, allowing for adequate grid preparation.

The energy generated by the fission of a single uranium pellet, roughly the size of a gummy bear, is equal to,

1 ton of coal

120 gallons of crude oil

17,000 cubic feet of natural gas

Due to the incredible power contained in uranium, we can generate massive amounts of around-the-clock, clean energy with fewer inputs, with a smaller land footprint, and replace fossil fuel plants altogether.

Read more on the energy efficiency of nuclear energy here.

With the growing concern surrounding climate change and energy reliability, our efforts to decarbonize need to utilize all available low-carbon energy sources. Nuclear stands out as an efficient, stable, and clean energy source that is able to provide abundant power for any nation. In fact, most prominent scientific bodies agree nuclear energy is needed in our fight against climate change.

• In the latest IPCC WG3 Climate Report it states that a 90% increase in nuclear capacity is needed by 2050 to limit the warming to 1.5 degrees.

• According to the UN Economic Commission for Europe, “nuclear power is demonstrably a source of electricity and a vital tool for successfully helping the world mitigate the effects of climate change.”

• According to the International Energy Agency, nuclear power capacity needs to double by 2050 if net zero goals are to be achieved and lifetime extensions of existing nuclear power plants are one of the most cost-effective sources of low-emission electricity.

• In a report by the International Atomic Energy Agency, they found that nuclear power has made significant contributions to carbon avoidance in the past, and in order “to support the Paris Agreement 2°C goal, nuclear capacity must more than double the current level worldwide.”

• In a summary by the World Economic Forum, they conclude, “nuclear technology could sustain the deployment of renewables, provide a stable and secure baseload and allow the planet to meet the necessary carbon-free targets set by the Paris Agreement.”

At the 2023, World Climate Action Summit (COP 28) in Dubai, more than 20 countries signed a pledge to triple global nuclear capacity by 2050. The countries, from four continents, recognized nuclear energy as a crucial technology to achieving a carbon-neutral future and highlighted the need for international cooperation and financing.

As we consider potential paths to decarbonization, renewables aren't the end goal; low-carbon energy is. Each state/nation must evaluate its energy needs and nearly fully decarbonized resources to determine what works best for its energy future. The only nations to have nearly fully decarbonized their electricity sectors have done it with either hydro and/or nuclear.

In general, an increase in heatwaves and severity of weather events affects ALL energy sources, not just nuclear energy.

With the vast majority of extreme weather events it is the damage and destruction to transmission lines in the grid outside of the plant rather than internal problems that cause generation to cease.

Heat waves and Drought

Water is a vital resource in the operation of existing nuclear plants. As hydrological systems change, certain climate areas will be more susceptible to droughts and heatwave events. High temperatures can affect operating systems within the plant and water coolant efficiency.

Although drought conditions can put a strain on operation efficiency, heatwaves hinder/restrict operation more frequently at freshwater and river-based sites due to thermal regulations of discharge water. This is because the temperature of the source of coolant water increases during these events. Sometimes river temperatures exceed the allowed temperature before any nuclear plant discharge.

For example, during heatwave events, water coolant efficiency at river-based nuclear plants has been subject to curtailment (reduced electricity production) based on conservative environmental, and water discharge temperature regulations to protect and minimize any potential harm or disruption to river aquatic life.

In 2022, France had to issue temporary waivers during heatwaves to allow nuclear stations to continue operating and discharge hot water into rivers at levels slightly above regulated levels. The French nuclear regulator, Autorité de Sûreté Nucléaire (ASN) explained that this temporary operation modification was essential to the safety of the electrical network to avoid lapses in services.

In a report analyzing the European heatwaves of 2003, 2006, 2018, and 2019 on nuclear output, found even at times of peak curtailment, the availability of nuclear energy exceeded that of any other low-carbon electricity generating source.

But even plants built far from a large body of water can take innovative approaches to secure water supply and operate at high efficiency, as is the case with the Palo Verde Nuclear Plant in Tonopah, Arizona. Palo Verde, with 3 reactors each requiring 20,000 gallons of water per minute, utilizes wastewater from the Phoenix area. Over 90% of the plant’s effluent came from treated wastewater.

By contrast, coastal nuclear plants discharge into much larger bodies of water, dissipating the temperature effect. While still regulated, like other plants, the scale of temperature change within the ocean allows most coastal plants to operate largely uninterrupted. (This does not mean they can discharge water at any temperature, there are still temperature limits they must adhere to.)

Overall, adaptations to the existing fleet of reactors to optimize for performance under heat and drought can be difficult and expensive to build into existing sites. However, they can be done!

Possible solutions include redesigning pipes to reach deeper, colder water and installing new heat-exchange systems that can reduce the need for water. These solutions were demonstrated by many French nuclear plants that installed such systems after the country’s record 2003 heat wave.

As temperatures increase, sites looking to reduce consumption of water have two options.

Build recirculating wet cooling towers to reduce water withdrawal from rivers by 95%

Construct an artificial cooling pond/ reservoir to be used with cooling towers so that the plant can rely on this water source, reusing large amounts of water.

Hurricanes

Before any major weather event like a hurricane, nuclear operators and staff are monitoring the storm at least a week in advance and have set protocols for when winds reach a certain speed and water levels reach a certain height.

As weather preparation, plants inspect equipment to ensure water and wind will not cause damage, particularly emergency equipment like mobile pumps and backup generators. In addition, operators are trained every 6 weeks on how to handle situations like hurricanes. If there is energy loss outside the site during a hurricane the reactors automatically shutdown for safety.

In 2011, 24 reactors safely withstood Hurricane Irene. In 2017, nuclear plants in Texas and Florida safely endured Hurricanes Harvey and Irma. South Texas Project plant remained at 100 percent capacity. In 2020, reactors in Arkansas, Louisiana, and Texas remained at 100% capacity, even as Hurricane Laura hit the region as a Category 4 hurricane.

Hurricanes and typhoons have become the leading source of nuclear plant outages in North America and South and East Asia (as well as all other types of generating plants). Stormy weather conditions can result in partial or full power outages due to lightning damage to grid components including transformers, substations, and transmission lines, forcing nuclear plants to shutdown. Powerful storms also come with heavy rainfall, and flooding that can bring debris close to water intake canals, particularly at river-based plants. But it’s important to note that some reactors may opt to shut down preemptively in preparation for an incoming hurricane or typhoon. As earlier stated, however, several nuclear plants have continued to produce power, even during intense storms.

In the past three decades, nuclear outages due to climatic events have consistently increased. Using prediction models for extreme weather may and planning outages may be a key way to protect nuclear plants moving forward. Long term energy loss due to extreme weather at NPPs is expected to only be 1.4-2.4%, though it could be higher at specific sites.

Other types of energy are also susceptible to significant damage from extreme weather. A 500 kW PV system at the Humacao wast water treatment plant in Puerto Rico was severely damaged after Hurricane Maria passed directly over the plant, in 2017.

Hurricane Irma completely destroyed a 4.2 megawatt PV system on St. Thomas in 2017.

The high wind speeds from hurricanes can cause wind turbines to lose blades or for the supporting tower to buckle. Blades are relatively easy to replace but damage to the support tower is a serious problem.

With a warming world, climate scientists have warned of the impacts from the changes in our hydrology and rising sea levels. We expect to see some of the most powerful effects along the coast and will see an increase in coastal flooding, storm surges and high tide flooding due to sea level rise.

But tropical and subtropical river deltas will be the hardest hit by climate effects. Often, such river deltas are the sites of port cities, putting large populations at risk, like along the U.S. East Coast, the gulf, Coast, Asia, and islands across the globe.

However, countries like the Netherlands that have a third of its land area below sea level have developed the most sophisticated anti-flood system of dikes, pumps, and sand dunes demonstrating that with innovation communities can adapt. These structural engineering tools are being shared with fellow low lying countries, like Bangladesh. As climate change threatens coastal areas in the future, engineering innovation and knowledge can maintain and protect existing infrastructure and populations.

Nuclear plants are one such type of infrastructure that may need, based on location, to implement structural and equipment upgrades and adaptive systems to safeguard the plant.

Following Fukushima, the Borssele Nuclear Generating station in the Netherlands prioritized protection from floods and storms by constructing a sea wall and installing diesel generators with tanks in sealed rooms and invested in additional pumps.

Many global nuclear operators improved their emergency control measures, especially related to flooding. Since the accident, all coastal nuclear plants installed more powerful pumps, better power supplies, waterproof doors, and movable flood barriers.

All of the coastal nuclear plants in the U.S. are built and maintained to withstand worst case storm scenarios and have been updated to be secure against sea level rise and related effects like storm surge. With robust structural engineering, nuclear plants can be protected from sea level rise and other risks like flooding predicted to increase with climate change. That said, sea level rise is a remarkably slow process, that is watched and observed, allowing us ample time to implement necessary tools.

Since the inception of nuclear energy, its public popularity has ebbed and flowed drastically. Within the past 5 years, the world witnessed a substantial increase in support - among the Finnish, South African, and Polish public we find some of the highest percentages of support.

Only 11% of people in Finland said they have negative feelings about nuclear energy.

74% of South Africans said they support building a new nuclear plant.

75% of Polish people said they support the development of nuclear energy in a 2022 poll.

Even in countries that historically were opposed to nuclear (Germany, Belgium, Switzerland), polls showed increased overall support.

Internationally we find that largely due to jobs created and economic benefits to the community, populations near nuclear plants historically support the energy source at higher levels. According to researcher Ann Bisconti, when local workers are involved in the community, local towns view nuclear plants as their own and tend to support it. In the United States, polls found that 91% of residents living near nuclear plants in the United States have favorable attitudes towards their plants. In Poland, 74% of Polish locals living near proposed AP 1000 sites support the development.

Public opinion is not the only factor that motivates governments to back nuclear, but it must remain acceptable enough that leaders feel they won’t receive backlash. Since the 2021 global energy crisis, nuclear energy has become a popular choice for countries seeking to secure energy independence and reliability. Countries vulnerable to volatile energy supply prices like the Philippines and Indonesia adopted national energy plans including nuclear energy. Since then, several nuclear plants were restarted or extended, including Diablo Canyon, Germany’s last three reactors, and 10 of Japan’s shutdown reactors.

Click here to see our timeline tracking public opinion on nuclear energy since 2005.

There are currently 412 reactors in operation worldwide, producing 2,610 TWhs of electricity, making it the world’s 4th largest source of electricity, and the world’s 2nd largest source of clean energy. Of the 196 countries in the world, 32 possess nuclear energy.

In the United States, 93 reactors produce 18% of the nation’s electricity and produce 45.5% of its clean electricity.

In Europe, there are 168 reactors, producing 148,729 MWe, and 25% of the EU’s electricity production comes from nuclear energy. In 2020, 683,512 GWh were produced.

About 60 reactors are being built around the world in 15 countries, most notably China, India, and Russia. 100 reactors with a total gross capacity of about 100 GWe are on order or planned, and an additional over 300 are proposed. Most of the currently planned are in Asia due to fast-growing economies and rapidly rising electricity demand.

Turkey, Jordan, Poland, and Egypt all have plans to build their first civilian commercial nuclear reactor, and countries including the Philippines and Indonesia have added nuclear energy to their national plan.

Read more about nuclear on a global scale here.