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Saturday, February 16, 2019

Anti-nuclear movement

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120,000 people attended an anti-nuclear protest in Bonn, West Germany, on 14 October 1979, following the Three Mile Island accident.
 
Anti-nuclear demonstration in Colmar, north-eastern France, on 3 October 2009
 
Anti-Nuclear Power Plant Rally following the Fukushima Daiichi nuclear disaster on 19 September 2011 at Meiji Shrine complex in Tokyo, Japan

The anti-nuclear movement is a social movement that opposes various nuclear technologies. Some direct action groups, environmental movements, and professional organisations have identified themselves with the movement at the local, national, or international level. Major anti-nuclear groups include Campaign for Nuclear Disarmament, Friends of the Earth, Greenpeace, International Physicians for the Prevention of Nuclear War, Peace Action and the Nuclear Information and Resource Service. The initial objective of the movement was nuclear disarmament, though since the late 1960s opposition has included the use of nuclear power. Many anti-nuclear groups oppose both nuclear power and nuclear weapons. The formation of green parties in the 1970s and 1980s was often a direct result of anti-nuclear politics.

Scientists and diplomats have debated nuclear weapons policy since before the atomic bombings of Hiroshima and Nagasaki in 1945. The public became concerned about nuclear weapons testing from about 1954, following extensive nuclear testing in the Pacific. In 1963, many countries ratified the Partial Test Ban Treaty which prohibited atmospheric nuclear testing.

Some local opposition to nuclear power emerged in the early 1960s, and in the late 1960s some members of the scientific community began to express their concerns. In the early 1970s, there were large protests about a proposed nuclear power plant in Wyhl, West Germany. The project was cancelled in 1975 and anti-nuclear success at Wyhl inspired opposition to nuclear power in other parts of Europe and North America. Nuclear power became an issue of major public protest in the 1970s and while opposition to nuclear power continues, increasing public support for nuclear power has re-emerged over the last decade in light of growing awareness of global warming and renewed interest in all types of clean energy.

A protest against nuclear power occurred in July 1977 in Bilbao, Spain, with up to 200,000 people in attendance. Following the Three Mile Island accident in 1979, an anti-nuclear protest was held in New York City, involving 200,000 people. In 1981, Germany's largest anti-nuclear power demonstration took place to protest against the Brokdorf Nuclear Power Plant west of Hamburg; some 100,000 people came face to face with 10,000 police officers. The largest protest was held on June 12, 1982, when one million people demonstrated in New York City against nuclear weapons. A 1983 nuclear weapons protest in West Berlin had about 600,000 participants. In May 1986, following the Chernobyl disaster, an estimated 150,000 to 200,000 people marched in Rome to protest against the Italian nuclear program. In the US, public opposition preceded the shutdown of the Shoreham, Yankee Rowe, Millstone 1, Rancho Seco, Maine Yankee, and many other nuclear power plants.

For many years after the 1986 Chernobyl disaster nuclear power was off the policy agenda in most countries, and the anti-nuclear power movement seemed to have won its case. Some anti-nuclear groups disbanded. In the 2000s (decade), however, following public relations activities by the nuclear industry, advances in nuclear reactor designs, and concerns about climate change, nuclear power issues came back into energy policy discussions in some countries. The 2011 Japanese nuclear accidents subsequently undermined the nuclear power industry's proposed renaissance and revived nuclear opposition worldwide, putting governments on the defensive. As of 2016, countries such as Australia, Austria, Denmark, Greece, Malaysia, New Zealand, and Norway have no nuclear power stations and remain opposed to nuclear power. Germany, Italy, Spain, and Switzerland are phasing-out nuclear power Sweden formerly had a nuclear phase-out policy, aiming to end nuclear power generation in Sweden by 2010. On 5 February 2009, the Government of Sweden announced an agreement allowing for the replacement of existing reactors, effectively ending the phase-out policy. Globally, more nuclear power reactors have closed than opened in recent years.

History and issues

Roots of the movement

Worldwide nuclear testing totals, 1945–1998

The application of nuclear technology, as a source of energy and as an instrument of war, has been controversial. These issues are discussed in nuclear weapons debate, nuclear power debate, and uranium mining debate

Scientists and diplomats have debated nuclear weapons policy since before the Atomic bombings of Hiroshima and Nagasaki in 1945. The public became concerned about nuclear weapons testing from about 1954, following extensive nuclear testing in the Pacific. In 1961, at the height of the Cold War, about 50,000 women brought together by Women Strike for Peace marched in 60 cities in the United States to demonstrate against nuclear weapons. In 1963, many countries ratified the Partial Test Ban Treaty which prohibited atmospheric nuclear testing.

Some local opposition to nuclear power emerged in the early 1960s, and in the late 1960s some members of the scientific community began to express their concerns. In the early 1970s, there were large protests about a proposed nuclear power plant in Wyhl, Germany. The project was cancelled in 1975 and anti-nuclear success at Wyhl inspired opposition to nuclear power in other parts of Europe and North America. Nuclear power became an issue of major public protest in the 1970s.

Anti-nuclear perspectives

Concerns about nuclear weapons

The 18,000 km2 expanse of the Semipalatinsk Test Site (indicated in red), which covers an area the size of Wales. The Soviet Union conducted 456 nuclear tests at Semipalatinsk from 1949 until 1989 with little regard for their effect on the local people or environment. The full impact of radiation exposure was hidden for many years by Soviet authorities and has only come to light since the test site closed in 1991.

From an anti-nuclear point of view, there is a threat to modern civilization from global nuclear war by accidental or deliberate nuclear strike. Some climate scientists estimate that a war between two countries that resulted in 100 Hiroshima-size atomic explosions would cause significant loss of life, in the tens of millions from climatic effects alone and disabled future generation . Soot thrown up into the atmosphere could blanket the earth, causing food chain disruption in what is termed a nuclear winter.

Many anti-nuclear weapons groups cite the 1996 Advisory Opinion of the International Court of Justice, Legality of the Threat or Use of Nuclear Weapons, in which it found that 'the threat or use of nuclear weapons would generally be contrary to the rules of international law applicable in armed conflict'.

Ridding the world of nuclear weapons has been a cause for pacifists for decades. But more recently mainstream politicians and retired military leaders have advocated nuclear disarmament. In January 2007 an article in The Wall Street Journal, authored by Henry Kissinger, Bill Perry, George Shultz and Sam Nunn. These men were veterans of the cold-war who believed in using nuclear weapons for deterrence. But they now reversed their previous position and asserted that instead of making the world safer, nuclear weapons had become a source of extreme concern.

Since the 1970s, some countries have built their own second-strike capability of massive deterrence in the event of a military attack with weapons of mass destruction. Two examples of this second-strike capability are the Samson Option strategy of Israel, and the Dead Hand system of Russia. During the era of nuclear weapons testing many local communities were affected, and some are still affected by uranium mining, and radioactive waste disposal.

Concerns about nuclear power

Following the 2011 Japanese Fukushima nuclear disaster, authorities shut down the nation's 54 nuclear power plants. As of 2013, the Fukushima site remains highly radioactive, with some 160,000 evacuees still living in temporary housing, and some land will be unfarmable for centuries. The difficult cleanup job will take 40 or more years, and cost tens of billions of dollars.
 
The abandoned city of Prypiat, Ukraine, following the April 1986 Chernobyl disaster. The Chernobyl nuclear power plant is in the background.
 
President Jimmy Carter leaving the Three Mile Island accident for Middletown, Pennsylvania, 1 April 1979

There are large variations in peoples’ understanding of the issues surrounding nuclear power, including the technology itself, its deployment, climate change, and energy security. There is a wide spectrum of views and concerns over nuclear power and it remains a controversial area of public policy.

Many studies have shown that the public "perceives nuclear power as a very risky technology" and, around the world, nuclear energy has declined in popularity since the Fukushima Daiichi nuclear disaster. Anti-nuclear critics see nuclear power as a dangerous, expensive way to boil water to generate electricity. Opponents of nuclear power have raised a number of related concerns:
Of these concerns, nuclear accidents and disposal of long-lived radioactive waste have probably had the greatest public impact worldwide. Anti-nuclear campaigners point to the 2011 Fukushima nuclear emergency as proof that nuclear power can never be 100% safe.

In his book Global Fission: The Battle Over Nuclear Power, Jim Falk explores connections between technological concerns and political concerns. Falk suggests that concerns of citizen groups or individuals who oppose nuclear power have often focused initially on the "range of physical hazards which accompany the technology" and leads to a "concern over the political relations of the nuclear industry" A more neutral observer might observe that this is nothing more than a conspiracy theory. Baruch Fischhoff, a social science professor said that many people really do not trust the nuclear industry.

M.V. Ramana says that "distrust of the social institutions that manage nuclear energy is widespread", and a 2001 survey by the European Commission found that "only 10.1 percent of Europeans trusted the nuclear industry". This public distrust is periodically reinforced by nuclear safety violations, or through ineffectiveness or corruption of the nuclear regulatory authorities. Once lost, says Ramana, trust is extremely difficult to regain.

Faced with public antipathy, the nuclear industry has "tried a variety of strategies to persuade the public to accept nuclear power", including the publication of numerous "fact sheets" that discuss issues of public concern. M.V. Ramana says that none of these strategies have been very successful. Nuclear proponents have tried to regain public support by offering newer, safer, reactor designs. These designs include those that incorporate passive safety and Small Modular Reactors. While these reactor designs "are intended to inspire trust, they may have an unintended effect: creating distrust of older reactors that lack the touted safety features".

Since 2000 the nuclear industry has undertaken an international media and lobbying campaign to promote nuclear power as a solution to the greenhouse effect and climate change. Nuclear power, the industry says, emits no or negligible amounts of carbon dioxide. Anti-nuclear groups respond by saying that only reactor operation is free of carbon dioxide emissions. All other stages of the nuclear fuel chain – mining, milling, transport, fuel fabrication, enrichment, reactor construction, decommissioning and waste management – use fossil fuels and hence emit carbon dioxide.

In 2011, a French court fined Électricité de France (EDF) €1.5m and jailed two senior employees for spying on Greenpeace, including hacking into Greenpeace's computer systems. Greenpeace was awarded €500,000 in damages.

There is a wide range of published energy-related studies which conclude that energy efficiency programs and renewable power technologies are a better energy option than nuclear power plants. This diverse range of studies come from many different sources, across the political spectrum, and from various academic disciplines, which suggests that there is a consensus among many independent, non-partisan energy experts that nuclear power plants are a poor way to produce electrical power.

Other technologies

Protest against ITER in France, 2009
 
The international nuclear fusion project International Thermonuclear Experimental Reactor (ITER) is constructing the world's largest and most advanced experimental tokamak nuclear fusion reactor in the south of France. A collaboration between the European Union (EU), India, Japan, China, Russia, South Korea and the United States, the project aims to make a transition from experimental studies of plasma physics to electricity-producing fusion power plants. In 2005, Greenpeace International issued a press statement criticizing government funding of the ITER, believing the money should have been diverted to renewable energy sources and claiming that fusion energy would result in nuclear waste and nuclear weapons proliferation issues. A French association including about 700 anti-nuclear groups, Sortir du nucléaire (Get Out of Nuclear Energy), claimed that ITER was a hazard because scientists did not yet know how to manipulate the high-energy deuterium and tritium hydrogen isotopes used in the fusion process. According to most anti-nuclear groups, nuclear fusion power “remains a distant dream”. The World Nuclear Association have said that fusion "presents so far insurmountable scientific and engineering challenges". Construction of the ITER facility began in 2007, but the project has run into many delays and budget overruns. Several milestones of the project has already been finished, but the finishing date for First Plasma has been discussed and postponed many times with various conclusions. In late 2016, the ITER council agreed on an updated project schedule, with a planned First Plasma opening by 2025, nine years after the originally anticipated opening.

Some anti-nuclear groups advocate reduced reliance on reactor-produced medical radioisotopes, through the use of alternative radioisotope production and alternative clinical technologies. Cyclotrons are being increasingly used to produce medical radioisotopes to the point where nuclear reactors are no longer needed to make the most common medical isotopes.

Nuclear-free alternatives

Three renewable energy sources: solar energy, wind power, and hydroelectricity
 
The 150 MW Andasol Solar Power Station is a commercial parabolic trough solar thermal power plant, located in Spain. The Andasol plant uses tanks of molten salt to store solar energy so that it can continue generating electricity even when the sun isn't shining.
 
Photovoltaic SUDI shade is an autonomous and mobile station in France that provides energy for electric vehicles using solar energy.
 
Anti-nuclear groups say that reliance on nuclear energy can be reduced by adopting energy conservation and energy efficiency measures. Energy efficiency can reduce energy consumption while providing the same level of energy "services". Renewable energy flows involve natural phenomena such as sunlight, wind, tides, plant growth, and geothermal heat, as the International Energy Agency explains:
Renewable energy is derived from natural processes that are replenished constantly. In its various forms, it derives directly from the sun, or from heat generated deep within the earth. Included in the definition is electricity and heat generated from solar, wind, ocean, hydropower, biomass, geothermal resources, and biofuels and hydrogen derived from renewable resources.
Anti-nuclear groups also favor the use of renewable energy, such as hydro, wind power, solar power, geothermal energy and biofuel. According to the International Energy Agency renewable energy technologies are essential contributors to the energy supply portfolio, as they contribute to world energy security and provide opportunities for mitigating greenhouse gases. Fossil fuels are being replaced by clean, climate-stabilizing, non-depletable sources of energy. According to Lester R. Brown:
...the transition from coal, oil, and gas to wind, solar, and geothermal energy is well under way. In the old economy, energy was produced by burning something — oil, coal, or natural gas — leading to the carbon emissions that have come to define our economy. The new energy economy harnesses the energy in wind, the energy coming from the sun, and heat from within the earth itself.
In 2014 global wind power capacity expanded 16% to 369,553 MW. Yearly wind energy production is also growing rapidly and has reached around 4% of worldwide electricity usage, 11.4% in the EU, and it is widely used in Asia, and the United States. In 2014, worldwide installed photovoltaics capacity increased to 177 gigawatts (GW), sufficient to supply 1 percent of global electricity demands. Solar thermal energy stations operate in the United States and Spain, and as of 2016, the largest of these is the 392 MW Ivanpah Solar Electric Generating System in California. The world's largest geothermal power installation is The Geysers in California, with a rated capacity of 750 MW. Brazil has one of the largest renewable energy programs in the world, involving production of ethanol fuel from sugar cane, and ethanol now provides 18% of the country's automotive fuel. Ethanol fuel is also widely available in the United States. 

Greenpeace advocates a reduction of fossil fuels by 50% by 2050 as well as phasing out nuclear power, contending that innovative technologies can increase energy efficiency, and suggests that by 2050 most electricity will come from renewable sources. The International Energy Agency estimates that nearly 50% of global electricity supplies will need to come from renewable energy sources in order to halve carbon dioxide emissions by 2050 and minimize climate change impacts.

Mark Z. Jacobson, a Stanford professor, says producing all new energy with wind power, solar power, and hydropower by 2030 is feasible and existing energy supply arrangements could be replaced by 2050. Barriers to implementing the renewable energy plan are seen to be "primarily social and political, not technological or economic". Jacobson says that energy costs with a wind, solar, water system should be similar to today's energy costs. Many has since referred to Jacobson's work to justify advocating for all 100% renewables, however, in February, 2017, a group of twenty-one scientists published a critique of Jacobson's work and found that his analysis involves "errors, inappropriate methods and implausible assumptions" and failed to provide "credible evidence for rejecting the conclusions of previous analyses that point to the benefits of considering a broad portfolio of energy system options."

Anti-nuclear organizations

Members of Nevada Desert Experience hold a prayer vigil during the Easter period of 1982 at the entrance to the Nevada Test Site.
 
The anti-nuclear movement is a social movement which operates at the local, national, and international level. Various types of groups have identified themselves with the movement:
Anti-nuclear groups have undertaken public protests and acts of civil disobedience which have included occupations of nuclear plant sites. Other salient strategies have included lobbying, petitioning government authorities, influencing public policy through referendum campaigns and involvement in elections. Anti-nuclear groups have also tried to influence policy implementation through litigation and by participating in licensing proceedings.

Anti-nuclear power organizations have emerged in every country that has had a nuclear power program. Protest movements against nuclear power first emerged in the United States, at the local level, and spread quickly to Europe and the rest of the world. National nuclear campaigns emerged in the late 1970s. Fueled by the Three Mile Island accident and the Chernobyl disaster, the anti-nuclear power movement mobilized political and economic forces which for some years "made nuclear energy untenable in many countries". In the 1970s and 1980s, the formation of green parties was often a direct result of anti-nuclear politics (e.g., in Germany and Sweden).

Some of these anti-nuclear power organizations are reported to have developed considerable expertise on nuclear power and energy issues. In 1992, the chairman of the Nuclear Regulatory Commission said that "his agency had been pushed in the right direction on safety issues because of the pleas and protests of nuclear watchdog groups".

International organizations

Symbols

Anti-nuclear symbols

Activities

Large protests

Demonstration against French nuclear testing in 1995 in Paris
 
Demonstration in Lyon, France in the 1980s against nuclear tests
 
On 12 December 1982, 30,000 women held hands around the 6 miles (9.7 km) perimeter of the base, in protest against the decision to site American cruise missiles there.

In 1971, the town of Wyhl, in Germany, was a proposed site for a nuclear power station. In the years that followed, public opposition steadily mounted, and there were large protests. Television coverage of police dragging away farmers and their wives helped to turn nuclear power into a major issue. In 1975, an administrative court withdrew the construction license for the plant. The Wyhl experience encouraged the formation of citizen action groups near other planned nuclear sites.

In 1972, the nuclear disarmament movement maintained a presence in the Pacific, largely in response to French nuclear testing there. New Zealand activists sailed boats into the test zone, interrupting the testing program. In Australia, thousands of people joined protest marches in Adelaide, Melbourne, Brisbane, and Sydney. Scientists issued statements demanding an end to the nuclear tests. In Fiji, anti-nuclear activists formed an Against Testing on Mururoa organization.

In the Basque Country (Spain and France), a strong anti-nuclear movement emerged in 1973, which ultimately led to the abandonment of most of the planned nuclear power projects. On July 14, 1977, in Bilbao, between 150,000 and 200,000 people protested against the Lemoniz Nuclear Power Plant. This has been called the "biggest ever anti-nuclear demonstration".

In France, there were mass protests in the early 1970s, organized at nearly every planned nuclear site in France. Between 1975 and 1977, some 175,000 people protested against nuclear power in ten demonstrations. In 1977 there was a massive demonstration at the Superphénix breeder reactor in Creys-Malvillein which culminated in violence.

In West Germany, between February 1975 and April 1979, some 280,000 people were involved in seven demonstrations at nuclear sites. Several site occupations were also attempted. Following the Three Mile Island accident in 1979, some 120,000 people attended a demonstration against nuclear power in Bonn.

In the Philippines, there were many protests in the late 1970s and 1980s against the proposed Bataan Nuclear Power Plant, which was built but never operated.

In 1981, Germany's largest anti-nuclear power demonstration protested against the construction of the Brokdorf Nuclear Power Plant west of Hamburg. Some 100,000 people came face to face with 10,000 police officers.

In the late 1970s and early 1980s, the revival of the nuclear arms race, triggered a new wave of protests about nuclear weapons. Older organizations such as the Federation of Atomic Scientists revived, and newer organizations appeared, including the Nuclear Weapons Freeze Campaign and Physicians for Social Responsibility. In the UK, on 1 April 1983, about 70,000 people linked arms to form a 14-mile-long human chain between three nuclear weapons centers in Berkshire.

On Palm Sunday 1982, 100,000 Australians participated in anti-nuclear rallies in the nation's largest cities. Growing year by year, the rallies drew 350,000 participants in 1985.

In May 1986, following the Chernobyl disaster, clashes between anti-nuclear protesters and West German police were common. More than 400 people were injured in mid-May at a nuclear-waste reprocessing plant being built near Wackersdorf. Also in May 1986, an estimated 150,000 to 200,000 people marched in Rome to protest against the Italian nuclear program, and 50,000 marched in Milan. Hundreds of people walked from Los Angeles to Washington, D.C. in 1986 in what is referred to as the Great Peace March for Global Nuclear Disarmament. The march took nine months to traverse 3,700 miles (6,000 km), advancing approximately fifteen miles per day.

The anti-nuclear organisation "Nevada Semipalatinsk" was formed in 1989 and was one of the first major anti-nuclear groups in the former Soviet Union. It attracted thousands of people to its protests and campaigns which eventually led to the closure of the nuclear test site in north-east Kazakhstan, in 1991.

The World Uranium Hearing was held in Salzburg, Austria in September 1992. Anti-nuclear speakers from all continents, including indigenous speakers and scientists, testified to the health and environmental problems of uranium mining and processing, nuclear power, nuclear weapons, nuclear tests, and radioactive waste disposal. People who spoke at the 1992 Hearing included: Thomas Banyacya, Katsumi Furitsu, Manuel Pino and Floyd Red Crow Westerman.

Protests in the United States

Anti-nuclear protest in 1979 following the Three Mile Island accident
 
April 2011 OREPA rally at the Y-12 weapons plant entrance
 
There were many anti-nuclear protests in the United States which captured national public attention during the 1970s and 1980s. These included the well-known Clamshell Alliance protests at Seabrook Station Nuclear Power Plant and the Abalone Alliance protests at Diablo Canyon Nuclear Power Plant, where thousands of protesters were arrested. Other large protests followed the 1979 Three Mile Island accident.

A large anti-nuclear demonstration was held in May 1979 in Washington, D.C., when 65,000 people including the Governor of California, attended a march and rally against nuclear power. In New York City on September 23, 1979, almost 200,000 people attended a protest against nuclear power. Anti-nuclear power protests preceded the shutdown of the Shoreham, Yankee Rowe, Millstone I, Rancho Seco, Maine Yankee, and about a dozen other nuclear power plants.

On June 12, 1982, one million people demonstrated in New York City's Central Park against nuclear weapons and for an end to the cold war arms race. It was the largest anti-nuclear protest and the largest political demonstration in American history. International Day of Nuclear Disarmament protests were held on June 20, 1983 at 50 sites across the United States. In 1986, hundreds of people walked from Los Angeles to Washington, D.C. in the Great Peace March for Global Nuclear Disarmament. There were many Nevada Desert Experience protests and peace camps at the Nevada Test Site during the 1980s and 1990s.

On May 1, 2005, 40,000 anti-nuclear/anti-war protesters marched past the United Nations in New York, 60 years after the atomic bombings of Hiroshima and Nagasaki. This was the largest anti-nuclear rally in the U.S. for several decades. In the 2000s there were protests about, and campaigns against, several new nuclear reactor proposals in the United States. In 2013, four aging, uncompetitive, reactors were permanently closed: San Onofre 2 and 3 in California, Crystal River 3 in Florida, and Kewaunee in Wisconsin. Vermont Yankee, in Vernon, is scheduled to close in 2014, following many protests. Protesters in New York State are seeking to close Indian Point Energy Center, in Buchanan, 30 miles from New York City.

Recent developments

For many years after the 1986 Chernobyl disaster nuclear power was off the policy agenda in most countries, and the anti-nuclear power movement seemed to have won its case. Some anti-nuclear groups disbanded. In the 2000s (decade), however, following public relations activities by the nuclear industry, advances in nuclear reactor designs, and concerns about climate change, nuclear power issues came back into energy policy discussions in some countries. The Fukushima Daiichi nuclear disaster subsequently undermined the nuclear power industry's proposed come back.
2004–2006
In January 2004, up to 15,000 anti-nuclear protesters marched in Paris against a new generation of nuclear reactors, the European Pressurized Water Reactor (EPWR).

On May 1, 2005, 40,000 anti-nuclear/anti-war protesters marched past the United Nations in New York, 60 years after the atomic bombings of Hiroshima and Nagasaki. This was the largest anti-nuclear rally in the U.S. for several decades. In Britain, there were many protests about the government's proposal to replace the aging Trident weapons system with a newer model. The largest protest had 100,000 participants and, according to polls, 59 percent of the public opposed the move.
2007–2009
A scene from the 2007 Stop EPR (European Pressurized Reactor) protest in Toulouse, France
 
Anti-nuclear protest near nuclear waste disposal center at Gorleben in Northern Germany, on 8 November 2008
 
Anti-nuclear march from London to Geneva, 2008
 
Start of anti-nuclear march from Geneva to Brussels, 2009
 
On March 17, 2007 simultaneous protests, organized by Sortir du nucléaire, were staged in five French towns to protest construction of EPR plants; Rennes, Lyon, Toulouse, Lille, and Strasbourg.

In June 2007, 4,000 local residents, students and anti-nuclear activists took to the streets in the city of Kudzus in Indonesia's Central Java, calling on the Government to abandon plans to build a nuclear power plant there.

In February 2008, a group of concerned scientists and engineers called for the closure of the Kazantzakis-Kariwa Nuclear Power Plant in Japan.

The International Conference on Nuclear Disarmament took place in Oslo in February 2008, and was organized by The Government of Norway, the Nuclear Threat Initiative and the Hoover Institute. The Conference was entitled Achieving the Vision of a World Free of Nuclear Weapons and had the purpose of building consensus between nuclear weapon states and non-nuclear weapon states in relation to the Nuclear Non-proliferation Treaty.

During a weekend in October 2008, some 15,000 people disrupted the transport of radioactive nuclear waste from France to a dump in Germany. This was one of the largest such protests in many years and, according to Der Spiel, it signals a revival of the anti-nuclear movement in Germany. In 2009, the coalition of green parties in the European parliament, who are unanimous in their anti-nuclear position, increased their presence in the parliament from 5.5% to 7.1% (52 seats).

In October 2008 in the United Kingdom, more than 30 people were arrested during one of the largest anti-nuclear protests at the Atomic Weapons Establishment at Aldermaston for 10 years. The demonstration marked the start of the UN World Disarmament Week and involved about 400 people.

In 2008 and 2009, there have been protests about, and criticism of, several new nuclear reactor proposals in the United States. There have also been some objections to license renewals for existing nuclear plants.

A convoy of 350 farm tractors and 50,000 protesters took part in an anti-nuclear rally in Berlin on September 5, 2009. The marchers demanded that Germany close all nuclear plants by 2020 and close the Gorleben radioactive dump. Gorleben is the focus of the anti-nuclear movement in Germany, which has tried to derail train transports of waste and to destroy or block the approach roads to the site. Two above-ground storage units house 3,500 containers of radioactive sludge and thousands of tonnes of spent fuel rods.
2010
KETTENreAKTION! in Uetersen, Germany
 
On April 21, 2010, a dozen environmental organizations called on the United States Nuclear Regulatory Commission to investigate possible limitations in the AP1000 reactor design. These groups appealed to three federal agencies to suspend the licensing process because they believed containment in the new design is weaker than existing reactors.

On April 24, 2010, about 120,000 people built a human chain (KETTENreAKTION!) between the nuclear plants at Krümmel and Brunsbüttel. In this way they were demonstrating against the plans of the German government to extend the life of nuclear power reactors.

In May 2010, some 25,000 people, including members of peace organizations and 1945 atomic bomb survivors, marched for about two kilometers from downtown New York to the United Nations headquarters, calling for the elimination of nuclear weapons. In September 2010, German government policy shifted back toward nuclear energy, and this generated some new anti-nuclear sentiment in Berlin and beyond. On September 18, 2010, tens of thousands of Germans surrounded Chancellor Angela Merkel’s office in an anti-nuclear demonstration that organizers said was the biggest of its kind since the 1986 Chernobyl disaster. In October 2010, tens of thousands of people protested in Munich against the nuclear power policy of Angela Merkel's coalition government. The action was the largest anti-nuclear event in Bavaria for more than two decades. In November 2010, there were violent protests against a train carrying reprocessed nuclear waste in Germany. Tens of thousands of protesters gathered in Dannenberg to signal their opposition to the cargo. Around 16,000 police were mobilised to deal with the protests.

In December 2010, some 10,000 people (mainly fishermen, farmers and their families) turned out to oppose the Jaitapur Nuclear Power Project in the Maharashtra state of India, amid a heavy police presence.

In December 2010, five anti-nuclear weapons activists, including octogenarians and Jesuit priests, were convicted of conspiracy and trespass in Tacoma, US. They cut fences at Naval Base Kitsap-Bangor in 2009 to protest submarine nuclear weapons, and reached an area near where Trident nuclear warheads are stored in bunkers. Members of the group could face up to 10 years in prison.
2011
Anti-nuclear demonstration in Munich, Germany, March 2011
 
Eight of the seventeen operating reactors in Germany were permanently shut down following the March 2011 Fukushima nuclear disaster
 
Buddhist monks of Nipponzan-Myōhōji protest against nuclear power near the Diet of Japan in Tokyo on 5 April 2011.
 
Castor demonstration in Dannenberg, Germany, November 2011
 
In January 2011, five Japanese young people held a hunger strike for more than a week, outside the Prefectural Government offices in Yamaguchi City, to protest against the planned Kaminoseki Nuclear Power Plant near the environmentally sensitive Seto Inland Sea.

Following the Fukushima Daiichi nuclear disaster, anti-nuclear opposition intensified in Germany. On 12 March 2011, 60,000 Germans formed a 45-km human chain from Stuttgart to the Neckarwestheim power plant. On 14 March, 110,000 people protested in 450 other German towns, with opinion polls indicating 80% of Germans opposed the government's extension of nuclear power. On March 15, 2011, Angela Merkel said that seven nuclear power plants which went online before 1980 would be closed and the time would be used to study speedier renewable energy commercialization.

In March 2011, around 2,000 anti-nuclear protesters demonstrated in Taiwan for an immediate halt to the construction of the island's fourth nuclear power plant. The protesters were also opposed to plans to extend the lifespan of three existing nuclear plants.

In March 2011, more than 200,000 people took part in anti-nuclear protests in four large German cities, on the eve of state elections. Organizers called it the largest anti-nuclear demonstration the country has seen. Thousands of Germans demanding an end to the use of nuclear power took part in nationwide demonstrations on 2 April 2011. About 7,000 people took part in anti-nuclear protests in Bremen. About 3,000 people protested outside RWE's headquarters in Essen.

Citing the Fukushima nuclear disaster, environmental activists at a U.N. meeting in April 2011 "urged bolder steps to tap renewable energy so the world doesn't have to choose between the dangers of nuclear power and the ravages of climate change".

In mid-April, 17,000 people protested at two demonstrations in Tokyo against nuclear power.

In India, environmentalists, local farmers and fishermen have been protesting for months over the planned Jaitapur Nuclear Power Project six-reactor complex, 420 km south of Mumbai. If built, it would be one of the world's largest nuclear power complexes. Protests have escalated following Japan's Fukushima nuclear disaster and during two days of violent rallies in April 2011, a local man was killed and dozens were injured.

In May 2011, some 20,000 people turned out for Switzerland's largest anti-nuclear power demonstration in 25 years. Demonstrators marched peacefully near the Beznau Nuclear Power Plant, the oldest in Switzerland, which started operating 40 years ago. Days after the anti-nuclear rally, Cabinet decided to ban the building of new nuclear power reactors. The country’s five existing reactors would be allowed to continue operating, but "would not be replaced at the end of their life span".

In May 2011, 5,000 people joined a carnival-like anti-nuclear protest in Taipei City. This was part of a nationwide “No Nuke Action” protest, urging the government to stop construction of a Fourth Nuclear Plant and pursue a more sustainable energy policy.

On World Environment Day in June 2011, environmental groups demonstrated against Taiwan's nuclear power policy. The Taiwan Environmental Protection Union, together with 13 environmental groups and legislators, gathered in Taipei and protested against the nation’s three operating nuclear power plants and the construction of a fourth plant.

Three months after the Fukushima nuclear disaster, thousands of anti-nuclear protesters marched in Japan. Company workers, students, and parents with children rallied across Japan, "venting their anger at the government's handling of the crisis, carrying flags bearing the words 'No Nukes!' and 'No More Fukushima'."

In August 2011, about 2,500 people including farmers and fishermen marched in Tokyo. They are suffering heavy losses following the Fukushima nuclear disaster, and called for prompt compensation from plant operator TEPCO and the government.

In September 2011, anti-nuclear protesters, marching to the beat of drums, "took to the streets of Tokyo and other cities to mark six months since the March earthquake and tsunami and vent their anger at the government's handling of the nuclear crisis set off by meltdowns at the Fukushima power plant". Protesters called for a complete shutdown of Japanese nuclear power plants and demanded a shift in government policy toward alternative sources of energy. Among the protestors were four young men who started a 10-day hunger strike to bring about change in Japan's nuclear policy.

Tens of thousands of people marched in central Tokyo in September 2011, chanting "Sayonara nuclear power" and waving banners, to call on Japan's government to abandon atomic energy in the wake of the Fukushima nuclear disaster. Author Kenzaburō Ōe and musician Ryuichi Sakamoto were among the event's supporters.

Since the March 2011 Japanese Fukushima nuclear disaster, "populations around proposed Indian NPP sites have launched protests that are now finding resonance around the country, raising questions about atomic energy as a clean and safe alternative to fossil fuels". Assurances by Prime Minister Manmohan Singh that all safety measures will be implemented, have not been heeded, and there have thus been mass protests against the French-backed 9900 MW Jaitapur Nuclear Power Project in Maharashtra and the 2000 MW Koodankulam Nuclear Power Plant in Tamil Nadu. The state government of West Bengal state has also refused permission to a proposed 6000 MW facility where six Russian reactors were to be built. A Public Interest Litigation (PIL) has also been filed against the government’s civil nuclear program at the apex Supreme Court. The PIL specifically asks for the "staying of all proposed nuclear power plants till satisfactory safety measures and cost-benefit analyses are completed by independent agencies".

Michael Banach, the current Vatican representative to the International Atomic Energy Agency, told a conference in Vienna in September 2011 that the Japanese nuclear disaster created new concerns about the safety of nuclear plants globally. Auxiliary bishop of Osaka Michael Goro Matsuura said this serious nuclear power incident should be a lesson for Japan and other countries to abandon nuclear projects. He called on the worldwide Christian solidarity to provide wide support for this anti-nuclear campaign. Statements from bishops’ conferences in Korea and the Philippines called on their governments to abandon atomic power. Nobel laureate Kenzaburō Ōe has said Japan should decide quickly to abandon its nuclear reactors.

In the UK, in October 2011, more than 200 protesters blockaded the Hinkley Point C nuclear power station site. Members of the Stop New Nuclear alliance barred access to the site in protest at EDF Energy's plans to build two new reactors on the site.
2012
Protest at Neckarwestheim, Germany, 11 March 2012
 
In January 2012, 22 South Korean women's groups appealed for a nuclear free future, saying they believe nuclear weapons and power reactors "threaten our lives, the lives of our families and all living creatures". The women said they feel an enormous sense of crisis after the Fukushima nuclear disaster in March 2011, which demonstrated the destructive power of radiation in the disruption of human lives, environmental pollution, and food contamination.

Thousands of demonstrators took to the streets of Yokohama, Japan, on January 14–15, 2012, to show their support for a nuclear power-free world. The demonstration showed that organized opposition to nuclear power has gained momentum following the Fukushima nuclear disaster. The most immediate demand of the demonstrators was for the protection of rights, including basic human rights such as health care, for those affected by the Fukushima accident.

In January 2012, three hundred anti-nuclear protestors marched against plans to build a new nuclear power station at Wylfa in the UK. The march was organized by Pobl Atal Wylfa B, Greenpeace and Cymdeithas yr Iaith, which are supporting a farmer who is in dispute with Horizon.

On the anniversary of the 11 March earthquake and tsunami, protesters across Japan called for the abolishment of nuclear power and nuclear reactors. In Koriyama, Fukushima, 16,000 people called for the end of nuclear power. In Shizuoka Prefecture, 1,100 people appealed for the scrapping of the Hamaoka Nuclear Power Plant. In Tsuruga, Fukui, 1,200 people marched in the streets of the city of Tsuruga, the home of the Monju fast-breeder reactor prototype and other nuclear reactors. In Nagasaki and Hiroshima, anti-nuclear protesters and atomic-bomb survivors marched together and demanded that Japan should end its nuclear dependency.

Austrian Chancellor Werner Faymann expects anti-nuclear petition drives to start in at least six European Union countries in 2012 in an effort to have the EU abandon nuclear power. Under the EU's Lisbon Treaty, petitions that attract at least one million signatures can seek legislative proposals from the European Commission, which would pave the way for anti-nuclear activists to garner support.

In March 2012, about 2,000 people staged an anti-nuclear protest in Taiwan's capital following the massive tsunami that hit Japan one year ago. The protesters rallied in Taipei to renew calls for a nuclear-free island. They "want the government to scrap a plan to operate a newly constructed nuclear power plant – the fourth in densely populated Taiwan". Scores of aboriginal protesters "demanded the removal of 100,000 barrels of nuclear waste stored on their Orchid Island". 
 
In March 2012, hundreds of anti-nuclear demonstrators converged on the Australian headquarters of global mining giants BHP Billiton and Rio Tinto. The 500-strong march through southern Melbourne called for an end to uranium mining in Australia, and included speeches and performances by representatives of the expatriate Japanese community as well as Australia's Indigenous communities, who are concerned about the effects of uranium mining near tribal lands. There were also events in Sydney.

In March 2012, South Korean environmental groups held a rally in Seoul to oppose nuclear power. Over 5,000 people attended, and the turnout was one of the largest in recent memory for an anti-nuclear rally. The demonstration demanded that President Lee Myung Bak abandon his policy of promoting nuclear power.

In March 2012, police said they had arrested nearly 200 anti-nuclear activists who were protesting the restart of work at the long-stalled Indian Kudankulam nuclear power plant.

In June 2012, tens of thousands of Japanese protesters participated in anti-nuclear power rallies in Tokyo and Osaka, over the government's decision to restart the first idled reactors since the Fukushima disaster, at Oi Nuclear Power Plant in Fukui Prefecture.
2013
Anti-nuclear protesters in Taipei

Thousands of protesters marched in Tokyo on March 11, 2013 calling on the government to reject nuclear power.

In March 2013, 68,000 Taiwanese protested across major cities against nuclear power and the island’s fourth nuclear plant, which is under construction. Taiwan's three existing nuclear plants are near the ocean, and prone to geological fractures, under the island.

In April 2013, thousands of Scottish campaigners, MSPs, and union leaders, rallied against nuclear weapons. The Scrap Trident Coalition wants to see an end to nuclear weapons, and says saved monies should be used for health, education and welfare initiatives. There was also a blockade of the Faslane Naval Base, where Trident missiles are stored.
2014
Anti-nuclear protesters shot with water cannons in Taiwan
 
In March 2014, around 130,000 Taiwanese marched for an anti-nuclear protest around Taiwan. They demanded that the government remove nuclear power plants in Taiwan. The march came ahead of the 3rd anniversary of Fukushima disaster. Around 50,000 people marched in Taipei while another three separate events were held around other Taiwanese cities attended by around 30,000 people. Among the participants are the organizations from Green Citizen Action's Alliance, Homemakers United Foundation, Taiwan Association for Human Rights and Taiwan Environmental Protection Union. Facing on-going opposition and a host of delays, construction of the Lungmen Nuclear Power Plant was halted in April 2014.

Casualties

Anti-nuclear demonstrations near Gorleben, Lower Saxony, Germany, 8 May 1996
 
Casualties during anti-nuclear protests include:
  • On 9 December 1982, Norman Mayer, an American anti–nuclear weapons activist, was shot and killed by the United States Park Police after threatening to blow up the Washington Monument, Washington, D.C., unless a national dialogue on the threat of nuclear weapons was seriously undertaken.
  • On 10 July 1985, the flagship of Greenpeace, Rainbow Warrior, was sunk by French agents in New Zealand waters, and a Greenpeace photographer was killed. The ship was involved in protests against nuclear weapons testing at Mururoa Atoll. The French Government initially denied any involvement with the sinking but eventually admitted its guilt in October 1985. Two French agents pleaded guilty to charges of manslaughter, and the French Government paid $7 million in damages.
  • In 1990, two pylons holding high-voltage power lines connecting the French and Italian grid were blown up by Italian eco-terrorists, and the attack is believed to have been directly in opposition against the Superphénix.
  • In 2004, activist Sébastien Briat, who had tied himself to train tracks in front of a shipment of reprocessed nuclear waste, was run over by the wheels of the train. The event happened in Avricourt, France, and the fuel (totaling 12 containers) was from a German plant, on its way to be reprocessed.

Impact

Impact on popular culture

Montage of film stills from the International Uranium Film Festival
 
Beginning in the 1950s, anti-nuclear ideas received coverage in the popular media with novels such as Fail-Safe and feature films such as Godzilla (1954),Dr. Strangelove or: How I Learned to Stop Worrying and Love the Bomb (1964), The China Syndrome (1979), Silkwood (1983), and The Rainbow Warrior (1992). 

Dr. Strangelove explored "what might happen within the Pentagon ... if some maniac Air Force general should suddenly order a nuclear attack on the Soviet Union". One reviewer called the movie "one of the cleverest and most incisive satiric thrusts at the awkwardness and folly of the military that has ever been on the screen".

The China Syndrome has been described as a "gripping 1979 drama about the dangers of nuclear power" which had an extra impact when the real-life accident at the Three Mile Island nuclear plant occurred several weeks after the film opened. Jane Fonda plays a TV reporter who witnesses a near-meltdown (the "China syndrome" of the title) at a local nuclear plant, which was averted by a quick-thinking engineer, played by Jack Lemmon. The plot suggests that corporate greed and cost-cutting "have led to potentially deadly faults in the plant's construction".

Silkwood was inspired by the true-life story of Karen Silkwood, who died in a suspicious car accident while investigating alleged wrongdoing at the Kerr-McGee plutonium plant where she worked.

Dark Circle is a 1982 American documentary film that focuses on the connections between the nuclear weapons and the nuclear power industries, with a strong emphasis on the individual human and protracted U.S. environmental costs involved. A clear point made by the film is that while only two bombs were dropped on Japan, many hundreds were exploded in the United States. The film won the Grand Prize for documentary at the Sundance Film Festival and received a national Emmy Award for "Outstanding individual achievement in news and documentary." For the opening scenes and about half of its length, the film focuses on the Rocky Flats Plant and its plutonium contamination of the area's environment

Ashes to Honey (ミツバチの羽音と地球の回転 Mitsubashi no haoto to chikyū no kaiten), (literally "Humming of Bees and Rotation of the Earth") is a Japanese documentary directed by Hitomi Kamanaka and released in 2010. It is the third in Kamanaka's trilogy of films on the problems of nuclear power and radiation, preceded by Hibakusha at the End of the World (also known as Radiation: A Slow Death) and Rokkasho Rhapsody.

Nuclear Tipping Point is a 2010 documentary film produced by the Nuclear Threat Initiative. It features interviews with four American government officials who were in office during the Cold War period, but are now advocating for the elimination of nuclear weapons. They are: Henry Kissinger, George Shultz, Sam Nunn, and William Perry.

Musicians United for Safe Energy (MUSE) was a musical group founded in 1979 by Jackson Browne, Graham Nash, Bonnie Raitt, and John Hall, following the Three Mile Island nuclear accident. The group organized a series of five No Nukes concerts held at Madison Square Garden in New York City in September 1979. On September 23, 1979, almost 200,000 people attended a large anti-nuclear rally staged by MUSE on the then-empty north end of the Battery Park City landfill in New York. The album No Nukes, and a film, also titled No Nukes, were both released in 1980 to document the performances. 

In 2007, Bonnie Raitt, Graham Nash, and Jackson Browne, as part of the No Nukes group, recorded a music video of the Buffalo Springfield song "For What It's Worth".

Impact on policy

U.S. and USSR/Russian nuclear weapons stockpiles, 1945–2005
 
A pair of billboards in Davis, California advertising its nuclear-free policy
 
The Bulletin of the Atomic Scientists is a nontechnical online magazine that has been published continuously since 1945, when it was founded by former Manhattan Projectphysicists after the atomic bombings of Hiroshima and Nagasaki. The Bulletin's primary aim is to inform the public about nuclear policy debates while advocating for the international control of nuclear weapons. One of the driving forces behind the creation of the Bulletin was the amount of public interest surrounding atomic energy at the dawn of the atomic age. In 1945 the public interest in atomic warfare and weaponry inspired contributors to the Bulletin to attempt to inform those interested about the dangers and destruction that atomic war could bring about. In the 1950s, the Bulletin was involved in the formation of the Pugwash Conferences on Science and World Affairs, annual conferences of scientists concerned about nuclear proliferation
 
Historian Lawrence S. Wittner has argued that anti-nuclear sentiment and activism led directly to government policy shifts about nuclear weapons. Public opinion influenced policymakers by limiting their options and also by forcing them to follow certain policies over others. Wittner credits public pressure and anti-nuclear activism with "Truman’s decision to explore the Baruch Plan, Eisenhower’s efforts towards a nuclear test ban and the 1958 testing moratorium, and Kennedy’s signing of the Partial Test Ban Treaty".

In terms of nuclear power, Forbes magazine, in the September 1975 issue, reported that "the anti-nuclear coalition has been remarkably successful ... [and] has certainly slowed the expansion of nuclear power." California has banned the approval of new nuclear reactors since the late 1970s because of concerns over waste disposal, and some other U.S. states have a moratorium on construction of nuclear power plants. Between 1975 and 1980, a total of 63 nuclear units were canceled in the United States. Anti-nuclear activities were among the reasons, but the primary motivations were the overestimation of future demand for electricity and steadily increasing capital costs, which made the economics of new plants unfavorable.

The proliferation of nuclear weapons became a presidential priority issue for the Carter Administration in the late 1970s. To deal with proliferation problems, President Carter promoted stronger international control over nuclear technology, including nuclear reactor technology. Although a strong supporter of nuclear power generally, Carter turned against the breeder reactor because the plutonium it produced could be diverted into nuclear weapons.

For many years after the 1986 Chernobyl disaster nuclear power was off the policy agenda in most countries. In recent years, intense public relations activities by the nuclear industry, increasing evidence of climate change and failures to address it, have brought nuclear power issues back to the forefront of policy discussion in the nuclear renaissance countries. But some countries are not prepared to expand nuclear power and are still divesting themselves of their nuclear legacy, through nuclear power phase-out legislation.

Under the New Zealand Nuclear Free Zone, Disarmament, and Arms Control Act 1987, all territorial sea and land of New Zealand is declared a nuclear free zone. Nuclear-powered and nuclear-armed ships are prohibited from entering the country's territorial waters. Dumping of foreign radioactive waste and development of nuclear weapons in the country is outlawed. Despite common misconception, this act does not make nuclear power plants illegal, nor does it make radioactive medical treatments produced in overseas reactors illegal. A 2008 survey shows that 19% of New Zealanders favor nuclear power as the best energy source, while 77% prefer wind power as the best energy source.

On 26 February 1990, FW de Klerk issued orders to terminate the country's nuclear weapons program, which until then had been a state secret. South Africa becomes the first country in the world to voluntary give-up its nuclear weapons program.

Ireland, in 1999, had no plans to change its non-nuclear stance and pursue nuclear power in the future.

In the United States, the Navajo Nation forbids uranium mining and processing in its land.

In the United States, a 2007 University of Maryland survey showed that 73 percent of the public surveyed favours the elimination of all nuclear weapons, 64 percent support removing all nuclear weapons from high alert, and 59 percent support reducing U.S. and Russian nuclear stockpiles to 400 weapons each. Given the unpopularity of nuclear weapons, U.S. politicians have been wary of supporting new nuclear programs. Republican-dominated congresses "have defeated the Bush administration's plan to build so-called 'bunker-busters' and 'mini-nukes'."

The Megatons to Megawatts Program converts weapons-grade material from nuclear warheads into fuel for nuclear power plants.

Thirty-one countries operate nuclear power plants. Nine nations possess nuclear weapons:
Today, some 26,000 nuclear weapons remain in the arsenals of the nine nuclear powers, with thousands on hair-trigger alert. Although U.S., Russian, and British nuclear arsenals are shrinking in size, those in the four Asian nuclear nations—China, India, Pakistan, and North Korea—are growing, in large part because of tensions among them. This Asian arms race also has possibilities of bringing Japan into the nuclear club.
During Barack Obama's successful U.S. presidential election campaign, he advocated the abolition of nuclear weapons. Since his election he has reiterated this goal in several major policy addresses. In 2010, the Obama administration negotiated a new weapons accord with Russia for a reduction of the maximum number of deployed nuclear weapons on each side from 2,200 to between 1,500 and 1,675—a reduction of some 30 percent. In addition, President Obama has committed $15 billion over the next five years to improving the safety of the nuclear weapons stockpile.

Following the Fukushima Daiichi nuclear disaster, the Italian government put a one-year moratorium on plans to revive nuclear power. On 11–12 June 2011, Italian voters passed a referendum to cancel plans for new reactors. Over 94% of the electorate voted in favor of the construction ban, with 55% of the eligible voters participating, making the vote binding.

German Chancellor Angela Merkel's coalition announced on May 30, 2011, that Germany’s 17 nuclear power stations will be shut down by 2022, in a policy reversal following Japan's Fukushima I nuclear accidents and anti-nuclear protests within Germany. Seven of the German power stations were closed temporarily in March, and they will remain off-line and be permanently decommissioned. An eighth was already off line, and will stay so.

As of 2011, countries such as Australia, Austria, Denmark, Greece, Ireland, Italy, Latvia, Liechtenstein, Luxembourg, Malta, Portugal, Israel, Malaysia, New Zealand, and Norway remain opposed to nuclear power. Germany and Switzerland are phasing-out nuclear power.

Public opinion surveys on nuclear issues

In 2005, the International Atomic Energy Agency presented the results of a series of public opinion surveys in the Global Public Opinion on Nuclear Issues report. Majorities of respondents in 14 of the 18 countries surveyed believe that the risk of terrorist acts involving radioactive materials at nuclear facilities is high, because of insufficient protection. While majorities of citizens generally support the continued use of existing nuclear power reactors, most people do not favour the building of new nuclear plants, and 25% of respondents feel that all nuclear power plants should be closed down. Stressing the climate change benefits of nuclear energy positively influences 10% of people to be more supportive of expanding the role of nuclear power in the world, but there is still a general reluctance to support the building of more nuclear power plants.

There is little support across the world for building new nuclear reactors, a 2011 poll for the BBC indicates. The global research agency GlobeScan, commissioned by BBC News, polled 23,231 people in 23 countries from July to September 2011, several months after the Fukushima nuclear disaster. In countries with existing nuclear programs, people are significantly more opposed than they were in 2005, with only the UK and US bucking the trend. Most believe that boosting energy efficiency and renewable energy can meet their needs.

Criticism

Stewart Brand wearing a shirt bearing the radioactive trefoil symbol with the caption "Rad."
Stewart Brand at a 2010 debate, "Does the world need nuclear energy?"
 
Attempts to reach political agreement on effective policies for climate change continue, and pro-nuclear environmentalists seek to reverse the traditionally anti-nuclear attitudes of environmentalists. Filmmaker Rob Stone's Pandora's Promise (2013) is a good example of this trend.

Some environmentalists criticise the anti-nuclear movement for under-stating the environmental costs of fossil fuels and non-nuclear alternatives, and overstating the environmental costs of nuclear energy. Of the numerous nuclear experts who have offered their expertise in addressing controversies, Bernard Cohen, Professor Emeritus of Physics at the University of Pittsburgh, is likely the most frequently cited. In his extensive writings he examines the safety issues in detail. He is best known for comparing nuclear safety to the relative safety of a wide range of other phenomena.

Anti-nuclear activists are accused of encouraging radiophobic emotions among the public. The War Against the Atom (Basic Books, 1982) Samuel MacCracken of Boston University argued that in 1982, 50,000 deaths per year could be attributed directly to non-nuclear power plants, if fuel production and transportation, as well as pollution, were taken into account. He argued that if non-nuclear plants were judged by the same standards as nuclear ones, each US non-nuclear power plant could be held responsible for about 100 deaths per year.

The Nuclear Energy Institute (NEI) is the main lobby group for companies doing nuclear work in the United States, while most countries that employ nuclear energy have a national industry group. The World Nuclear Association is the only global trade body. In seeking to counteract the arguments of nuclear opponents, it points to independent studies that quantify the costs and benefits of nuclear energy and compares them to the costs and benefits of alternatives. NEI sponsors studies of its own, but it also references studies performed for the World Health Organization, for the International Energy Agency, and by university researchers.

Critics of the anti-nuclear movement point to independent studies that show that the capital resources required for renewable energy sources are higher than those required for nuclear power.

Some people, including former opponents of nuclear energy, criticize the movement on the basis of the claim that nuclear power is necessary for reducing carbon dioxide emissions. These individuals include James Lovelock, originator of the Gaia hypothesis, Patrick Moore, a co-founder of Greenpeace and former director of Greenpeace International, George Monbiot and Stewart Brand, creator of the Whole Earth Catalog. Lovelock goes further to refute claims about the danger of nuclear energy and its waste products. In a January 2008 interview, Moore said that "It wasn't until after I'd left Greenpeace and the climate change issue started coming to the forefront that I started rethinking energy policy in general and realiszd that I had been incorrect in my analysis of nuclear as being some kind of evil plot."

Some anti-nuclear organizations have acknowledged that their positions are subject to review.

In April 2007, Dan Becker, Director of Global Warming for the Sierra Club, declared, "Switching from dirty coal plants to dangerous nuclear power is like giving up smoking cigarettes and taking up crack." James Lovelock criticizes holders of such a view: "Opposition to nuclear energy is based on irrational fear fed by Hollywood-style fiction, the Green lobbies and the media." ". . .I am a Green and I entreat my friends in the movement to drop their wrongheaded objection to nuclear energy."

George Monbiot, an English writer known for his environmental and political activism, once expressed deep antipathy to the nuclear industry. He finally rejected his later neutral position regarding nuclear power in March 2011. Although he "still loathe[s] the liars who run the nuclear industry", Monbiot now advocates its use, having been convinced of its relative safety by what he considers the limited effects of the 2011 Japan tsunami on nuclear reactors in the region. Subsequently, he has harshly condemned the anti-nuclear movement, writing that it "has misled the world about the impacts of radiation on human health ... made [claims] ungrounded in science, unsupportable when challenged and wildly wrong." He singled out Helen Caldicott for, he wrote, making unsourced and inaccurate claims, dismissing contrary evidence as part of a cover-up, and overstating the death toll from the Chernobyl disaster by a factor of more than 140.

Nuclear meltdown

From Wikipedia, the free encyclopedia

Three of the reactors at Fukushima I overheated because the cooling systems failed after a tsunami flooded the power station, causing core meltdowns. This was compounded by hydrogen gas explosions and the venting of contaminated steam which released large amounts of radioactive material into the air.
 
Three Mile Island Nuclear Generating Station consisted of two pressurized water reactors manufactured by Babcock & Wilcox, each inside its own containment building and connected cooling towers. Unit 2, which suffered a partial core melt, is in the background.

A nuclear meltdown (core melt accident or partial core melt) is a severe nuclear reactor accident that results in core damage from overheating. The term nuclear meltdown is not officially defined by the International Atomic Energy Agency or by the Nuclear Regulatory Commission. However, it has been defined to mean the accidental melting of the core of a nuclear reactor, and is in common usage a reference to the core's either complete or partial collapse. 

A core meltdown accident occurs when the heat generated by a nuclear reactor exceeds the heat removed by the cooling systems to the point where at least one nuclear fuel element exceeds its melting point. This differs from a fuel element failure, which is not caused by high temperatures. A meltdown may be caused by a loss of coolant, loss of coolant pressure, or low coolant flow rate or be the result of a criticality excursion in which the reactor is operated at a power level that exceeds its design limits. Alternatively, in a reactor plant such as the RBMK-1000, an external fire may endanger the core, leading to a meltdown. 

Once the fuel elements of a reactor begin to melt, the fuel cladding has been breached, and the nuclear fuel (such as uranium, plutonium, or thorium) and fission products (such as caesium-137, krypton-85, or iodine-131) within the fuel elements can leach out into the coolant. Subsequent failures can permit these radioisotopes to breach further layers of containment. Superheated steam and hot metal inside the core can lead to fuel-coolant interactions, hydrogen explosions, or water hammer, any of which could destroy parts of the containment. A meltdown is considered very serious because of the potential for radioactive materials to breach all containment and escape (or be released) into the environment, resulting in radioactive contamination and fallout, and potentially leading to radiation poisoning of people and animals nearby.

Causes

Nuclear power plants generate electricity by heating fluid via a nuclear reaction to run a generator. If the heat from that reaction is not removed adequately, the fuel assemblies in a reactor core can melt. A core damage incident can occur even after a reactor is shut down because the fuel continues to produce decay heat

A core damage accident is caused by the loss of sufficient cooling for the nuclear fuel within the reactor core. The reason may be one of several factors, including a loss-of-pressure-control accident, a loss-of-coolant accident (LOCA), an uncontrolled power excursion or, in reactors without a pressure vessel, a fire within the reactor core. Failures in control systems may cause a series of events resulting in loss of cooling. Contemporary safety principles of defense in depth ensure that multiple layers of safety systems are always present to make such accidents unlikely. 

The containment building is the last of several safeguards that prevent the release of radioactivity to the environment. Many commercial reactors are contained within a 1.2-to-2.4-metre (3.9 to 7.9 ft) thick pre-stressed, steel-reinforced, air-tight concrete structure that can withstand hurricane-force winds and severe earthquakes.
  • In a loss-of-coolant accident, either the physical loss of coolant (which is typically deionized water, an inert gas, NaK, or liquid sodium) or the loss of a method to ensure a sufficient flow rate of the coolant occurs. A loss-of-coolant accident and a loss-of-pressure-control accident are closely related in some reactors. In a pressurized water reactor, a LOCA can also cause a "steam bubble" to form in the core due to excessive heating of stalled coolant or by the subsequent loss-of-pressure-control accident caused by a rapid loss of coolant. In a loss-of-forced-circulation accident, a gas cooled reactor's circulators (generally motor or steam driven turbines) fail to circulate the gas coolant within the core, and heat transfer is impeded by this loss of forced circulation, though natural circulation through convection will keep the fuel cool as long as the reactor is not depressurized.
  • In a loss-of-pressure-control accident, the pressure of the confined coolant falls below specification without the means to restore it. In some cases this may reduce the heat transfer efficiency (when using an inert gas as a coolant) and in others may form an insulating "bubble" of steam surrounding the fuel assemblies (for pressurized water reactors). In the latter case, due to localized heating of the "steam bubble" due to decay heat, the pressure required to collapse the "steam bubble" may exceed reactor design specifications until the reactor has had time to cool down. (This event is less likely to occur in boiling water reactors, where the core may be deliberately depressurized so that the Emergency Core Cooling System may be turned on). In a depressurization fault, a gas-cooled reactor loses gas pressure within the core, reducing heat transfer efficiency and posing a challenge to the cooling of fuel; however, as long as at least one gas circulator is available, the fuel will be kept cool.
  • In an uncontrolled power excursion accident, a sudden power spike in the reactor exceeds reactor design specifications due to a sudden increase in reactor reactivity. An uncontrolled power excursion occurs due to significantly altering a parameter that affects the neutron multiplication rate of a chain reaction (examples include ejecting a control rod or significantly altering the nuclear characteristics of the moderator, such as by rapid cooling). In extreme cases the reactor may proceed to a condition known as prompt critical. This is especially a problem in reactors that have a positive void coefficient of reactivity, a positive temperature coefficient, are overmoderated, or can trap excess quantities of deleterious fission products within their fuel or moderators. Many of these characteristics are present in the RBMK design, and the Chernobyl disaster was caused by such deficiencies as well as by severe operator negligence. Western light water reactors are not subject to very large uncontrolled power excursions because loss of coolant decreases, rather than increases, core reactivity (a negative void coefficient of reactivity); "transients," as the minor power fluctuations within Western light water reactors are called, are limited to momentary increases in reactivity that will rapidly decrease with time (approximately 200% - 250% of maximum neutronic power for a few seconds in the event of a complete rapid shutdown failure combined with a transient).
  • Core-based fires endanger the core and can cause the fuel assemblies to melt. A fire may be caused by air entering a graphite moderated reactor, or a liquid-sodium cooled reactor. Graphite is also subject to accumulation of Wigner energy, which can overheat the graphite (as happened at the Windscale fire). Light water reactors do not have flammable cores or moderators and are not subject to core fires. Gas-cooled civilian reactors, such as the Magnox, UNGG, and AGCR type reactors, keep their cores blanketed with non reactive carbon dioxide gas, which cannot support a fire. Modern gas-cooled civilian reactors use helium, which cannot burn, and have fuel that can withstand high temperatures without melting.
  • Byzantine faults and cascading failures within instrumentation and control systems may cause severe problems in reactor operation, potentially leading to core damage if not mitigated. For example, the Browns Ferry fire damaged control cables and required the plant operators to manually activate cooling systems. The Three Mile Island accident was caused by a stuck-open pilot-operated pressure relief valve combined with a deceptive water level gauge that misled reactor operators, which resulted in core damage.

Light water reactors (LWRs)

The Three Mile Island reactor 2 after the meltdown.
  1. Inlet 2B
  2. Inlet 1A
  3. Cavity
  4. Loose core debris
  5. Crust
  6. Previously molten material
  7. Lower plenum debris
  8. Possible region depleted in uranium
  9. Ablated incore instrument guide
  10. Hole in baffle plate
  11. Coating of previously-molten material on bypass region interior surfaces
  12. Upper grid damage
Before the core of a light water nuclear reactor can be damaged, two precursor events must have already occurred:
  • A limiting fault (or a set of compounded emergency conditions) that leads to the failure of heat removal within the core (the loss of cooling). Low water level uncovers the core, allowing it to heat up.
  • Failure of the Emergency Core Cooling System (ECCS). The ECCS is designed to rapidly cool the core and make it safe in the event of the maximum fault (the design basis accident) that nuclear regulators and plant engineers could imagine. There are at least two copies of the ECCS built for every reactor. Each division (copy) of the ECCS is capable, by itself, of responding to the design basis accident. The latest reactors have as many as four divisions of the ECCS. This is the principle of redundancy, or duplication. As long as at least one ECCS division functions, no core damage can occur. Each of the several divisions of the ECCS has several internal "trains" of components. Thus the ECCS divisions themselves have internal redundancy – and can withstand failures of components within them.
The Three Mile Island accident was a compounded group of emergencies that led to core damage. What led to this was an erroneous decision by operators to shut down the ECCS during an emergency condition due to gauge readings that were either incorrect or misinterpreted; this caused another emergency condition that, several hours after the fact, led to core exposure and a core damage incident. If the ECCS had been allowed to function, it would have prevented both exposure and core damage. During the Fukushima incident the emergency cooling system had also been manually shut down several minutes after it started.

If such a limiting fault were to occur, and a complete failure of all ECCS divisions were to occur, both Kuan, et al and Haskin, et al describe six stages between the start of the limiting fault (the loss of cooling) and the potential escape of molten corium into the containment (a so-called "full meltdown"):
  1. Uncovering of the Core – In the event of a transient, upset, emergency, or limiting fault, LWRs are designed to automatically SCRAM (a SCRAM being the immediate and full insertion of all control rods) and spin up the ECCS. This greatly reduces reactor thermal power (but does not remove it completely); this delays core becoming uncovered, which is defined as the point when the fuel rods are no longer covered by coolant and can begin to heat up. As Kuan states: "In a small-break LOCA with no emergency core coolant injection, core uncovery [sic] generally begins approximately an hour after the initiation of the break. If the reactor coolant pumps are not running, the upper part of the core will be exposed to a steam environment and heatup of the core will begin. However, if the coolant pumps are running, the core will be cooled by a two-phase mixture of steam and water, and heatup of the fuel rods will be delayed until almost all of the water in the two-phase mixture is vaporized. The TMI-2 accident showed that operation of reactor coolant pumps may be sustained for up to approximately two hours to deliver a two phase mixture that can prevent core heatup."
  2. Pre-damage heat up – "In the absence of a two-phase mixture going through the core or of water addition to the core to compensate water boiloff, the fuel rods in a steam environment will heat up at a rate between 0.3 °C/s (0.5 °F/s) and 1 °C/s (1.8 °F/s) (3)."
  3. Fuel ballooning and bursting – "In less than half an hour, the peak core temperature would reach 1,100 K (830 °C). At this temperature the zircaloy cladding of the fuel rods may balloon and burst. This is the first stage of core damage. Cladding ballooning may block a substantial portion of the flow area of the core and restrict the flow of coolant. However, complete blockage of the core is unlikely because not all fuel rods balloon at the same axial location. In this case, sufficient water addition can cool the core and stop core damage progression."
  4. Rapid oxidation – "The next stage of core damage, beginning at approximately 1,500 K (1,230 °C), is the rapid oxidation of the Zircaloy by steam. In the oxidation process, hydrogen is produced and a large amount of heat is released. Above 1,500 K (1,230 °C), the power from oxidation exceeds that from decay heat (4,5) unless the oxidation rate is limited by the supply of either zircaloy or steam."
  5. Debris bed formation – "When the temperature in the core reaches about 1,700 K (1,430 °C), molten control materials (1,6) will flow to and solidify in the space between the lower parts of the fuel rods where the temperature is comparatively low. Above 1,700 K (1,430 °C), the core temperature may escalate in a few minutes to the melting point of zircaloy [2,150 K (1,880 °C)] due to increased oxidation rate. When the oxidized cladding breaks, the molten zircaloy, along with dissolved UO2 (1,7) would flow downward and freeze in the cooler, lower region of the core. Together with solidified control materials from earlier down-flows, the relocated zircaloy and UO2 would form the lower crust of a developing cohesive debris bed."
  6. (Corium) Relocation to the lower plenum – "In scenarios of small-break LOCAs, there is generally a pool of water in the lower plenum of the vessel at the time of core relocation. Release of molten core materials into water always generates large amounts of steam. If the molten stream of core materials breaks up rapidly in water, there is also a possibility of a steam explosion. During relocation, any unoxidized zirconium in the molten material may also be oxidized by steam, and in the process hydrogen is produced. Recriticality also may be a concern if the control materials are left behind in the core and the relocated material breaks up in unborated water in the lower plenum."
At the point at which the corium relocates to the lower plenum, Haskin, et al relate that the possibility exists for an incident called a fuel-coolant interaction (FCI) to substantially stress or breach the primary pressure boundary when the corium relocates to the lower plenum of the reactor pressure vessel ("RPV"). This is because the lower plenum of the RPV may have a substantial quantity of water - the reactor coolant - in it, and, assuming the primary system has not been depressurized, the water will likely be in the liquid phase, and consequently dense, and at a vastly lower temperature than the corium. Since corium is a liquid metal-ceramic eutectic at temperatures of 2,200 to 3,200 K (1,930 to 2,930 °C), its fall into liquid water at 550 to 600 K (277 to 327 °C) may cause an extremely rapid evolution of steam that could cause a sudden extreme overpressure and consequent gross structural failure of the primary system or RPV. Though most modern studies hold that it is physically infeasible, or at least extraordinarily unlikely, Haskin, et al state that there exists a remote possibility of an extremely violent FCI leading to something referred to as an alpha-mode failure, or the gross failure of the RPV itself, and subsequent ejection of the upper plenum of the RPV as a missile against the inside of the containment, which would likely lead to the failure of the containment and release of the fission products of the core to the outside environment without any substantial decay having taken place.

The American Nuclear Society has commented on the TMI-2 accident, that despite melting of about one-third of the fuel, the reactor vessel itself maintained its integrity and contained the damaged fuel.

Breach of the Primary Pressure Boundary

There are several possibilities as to how the primary pressure boundary could be breached by corium.
  • Steam Explosion
As previously described, FCI could lead to an overpressure event leading to RPV fail, and thus, primary pressure boundary fail. Haskin, et al. report that in the event of a steam explosion, failure of the lower plenum is far more likely than ejection of the upper plenum in the alpha-mode. In the event of lower plenum failure, debris at varied temperatures can be expected to be projected into the cavity below the core. The containment may be subject to overpressure, though this is not likely to fail the containment. The alpha-mode failure will lead to the consequences previously discussed.
  • Pressurized Melt Ejection (PME)
It is quite possible, especially in pressurized water reactors, that the primary loop will remain pressurized following corium relocation to the lower plenum. As such, pressure stresses on the RPV will be present in addition to the weight stress that the molten corium places on the lower plenum of the RPV; when the metal of the RPV weakens sufficiently due to the heat of the molten corium, it is likely that the liquid corium will be discharged under pressure out of the bottom of the RPV in a pressurized stream, together with entrained gases. This mode of corium ejection may lead to direct containment heating (DCH).

Severe Accident Ex-Vessel Interactions and Challenges to Containment

Haskin, et al identify six modes by which the containment could be credibly challenged; some of these modes are not applicable to core melt accidents.
  1. Overpressure
  2. Dynamic pressure (shockwaves)
  3. Internal missiles
  4. External missiles (not applicable to core melt accidents)
  5. Meltthrough
  6. Bypass

Standard failure modes

If the melted core penetrates the pressure vessel, there are theories and speculations as to what may then occur. 

In modern Russian plants, there is a "core catching device" in the bottom of the containment building. The melted core is supposed to hit a thick layer of a "sacrificial metal" which would melt, dilute the core and increase the heat conductivity, and finally the diluted core can be cooled down by water circulating in the floor. However, there has never been any full-scale testing of this device.

In Western plants there is an airtight containment building. Though radiation would be at a high level within the containment, doses outside of it would be lower. Containment buildings are designed for the orderly release of pressure without releasing radionuclides, through a pressure release valve and filters. Hydrogen/oxygen recombiners also are installed within the containment to prevent gas explosions. 

In a melting event, one spot or area on the RPV will become hotter than other areas, and will eventually melt. When it melts, corium will pour into the cavity under the reactor. Though the cavity is designed to remain dry, several NUREG-class documents advise operators to flood the cavity in the event of a fuel melt incident. This water will become steam and pressurize the containment. Automatic water sprays will pump large quantities of water into the steamy environment to keep the pressure down. Catalytic recombiners will rapidly convert the hydrogen and oxygen back into water. One positive effect of the corium falling into water is that it is cooled and returns to a solid state. 

Extensive water spray systems within the containment along with the ECCS, when it is reactivated, will allow operators to spray water within the containment to cool the core on the floor and reduce it to a low temperature. 

These procedures are intended to prevent release of radioactivity. In the Three Mile Island event in 1979, a theoretical person standing at the plant property line during the entire event would have received a dose of approximately 2 millisieverts (200 millirem), between a chest X-ray's and a CT scan's worth of radiation. This was due to outgassing by an uncontrolled system that, today, would have been backfitted with activated carbon and HEPA filters to prevent radionuclide release. 

However in the Fukushima incident, this design failed: Despite the efforts of the operators at the Fukushima Daiichi nuclear power plant to maintain control, the reactor cores in units 1-3 overheated, the nuclear fuel melted and the three containment vessels were breached. Hydrogen was released from the reactor pressure vessels, leading to explosions inside the reactor buildings in units 1, 3 and 4 that damaged structures and equipment and injured personnel. Radionuclides were released from the plant to the atmosphere and were deposited on land and on the ocean. There were also direct releases into the sea.

As the natural decay heat of the corium eventually reduces to an equilibrium with convection and conduction to the containment walls, it becomes cool enough for water spray systems to be shut down and the reactor to be put into safe storage. The containment can be sealed with release of extremely limited offsite radioactivity and release of pressure. After perhaps a decade for fission products to decay, the containment can be reopened for decontamination and demolition. 

Another scenario sees a buildup of potentially explosive hydrogen, but passive autocatalytic recombiners inside the containment are designed to prevent this. In Fukushima, the containments were filled with inert nitrogen which prevented hydrogen from burning; however, the hydrogen leaked from the containment to the reactor building, where it mixed with air and exploded. During the 1979 Three Mile Island accident, a hydrogen bubble formed in the pressure vessel dome. There were initial concerns that the hydrogen might ignite and damage the pressure vessel or even the containment building; but it was soon realized that lack of oxygen prevented burning or explosion.

Speculative failure modes

One scenario consists of the reactor pressure vessel failing all at once, with the entire mass of corium dropping into a pool of water (for example, coolant or moderator) and causing extremely rapid generation of steam. The pressure rise within the containment could threaten integrity if rupture disks could not relieve the stress. Exposed flammable substances could burn, but there are few, if any, flammable substances within the containment. 

Another theory, called an 'alpha mode' failure by the 1975 Rasmussen (WASH-1400) study, asserted steam could produce enough pressure to blow the head off the reactor pressure vessel (RPV). The containment could be threatened if the RPV head collided with it. (The WASH-1400 report was replaced by better-based newer studies, and now the Nuclear Regulatory Commission has disavowed them all and is preparing the overarching State-of-the-Art Reactor Consequence Analyses [SOARCA] study - see the Disclaimer in NUREG-1150.) 

By 1970, there were doubts about the ability of the emergency cooling systems of a nuclear reactor to prevent a loss-of-coolant accident and the consequent meltdown of the fuel core; the subject proved popular in the technical and the popular presses. In 1971, in the article Thoughts on Nuclear Plumbing, former Manhattan Project nuclear physicist Ralph Lapp used the term "China syndrome" to describe a possible burn-through of the containment structures, and the subsequent escape of radioactive material(s) into the atmosphere and environment. The hypothesis derived from a 1967 report by a group of nuclear physicists, headed by W. K. Ergen. Some fear that a molten reactor core could penetrate the reactor pressure vessel and containment structure and burn downwards to the level of the groundwater.

It has not been determined to what extent a molten mass can melt through a structure (although that was tested in the Loss-of-Fluid-Test Reactor described in Test Area North's fact sheet). The Three Mile Island accident provided real-life experience with an actual molten core: the corium failed to melt through the Reactor Pressure Vessel after over six hours of exposure, due to dilution of the melt by the control rods and other reactor internals, validating the emphasis on defense in depth against core damage incidents.

Other reactor types

Other types of reactors have different capabilities and safety profiles than the LWR does. Advanced varieties of several of these reactors have the potential to be inherently safe.

CANDU reactors

CANDU reactors, Canadian-invented deuterium-uranium design, are designed with at least one, and generally two, large low-temperature and low-pressure water reservoirs around their fuel/coolant channels. The first is the bulk heavy-water moderator (a separate system from the coolant), and the second is the light-water-filled shield tank(or calandria vault). These backup heat sinks are sufficient to prevent either the fuel meltdown in the first place (using the moderator heat sink), or the breaching of the core vessel should the moderator eventually boil off (using the shield tank heat sink). Other failure modes aside from fuel melt will probably occur in a CANDU rather than a meltdown, such as deformation of the calandria into a non-critical configuration. All CANDU reactors are located within standard Western containments as well.

Gas-cooled reactors

One type of Western reactor, known as the advanced gas-cooled reactor (or AGR), built by the United Kingdom, is not very vulnerable to loss-of-cooling accidents or to core damage except in the most extreme of circumstances. By virtue of the relatively inert coolant (carbon dioxide), the large volume and high pressure of the coolant, and the relatively high heat transfer efficiency of the reactor, the time frame for core damage in the event of a limiting fault is measured in days. Restoration of some means of coolant flow will prevent core damage from occurring. 

Other types of highly advanced gas cooled reactors, generally known as high-temperature gas-cooled reactors (HTGRs) such as the Japanese High Temperature Test Reactor and the United States' Very High Temperature Reactor, are inherently safe, meaning that meltdown or other forms of core damage are physically impossible, due to the structure of the core, which consists of hexagonal prismatic blocks of silicon carbide reinforced graphite infused with TRISO or QUADRISO pellets of uranium, thorium, or mixed oxide buried underground in a helium-filled steel pressure vessel within a concrete containment. Though this type of reactor is not susceptible to meltdown, additional capabilities of heat removal are provided by using regular atmospheric airflow as a means of backup heat removal, by having it pass through a heat exchanger and rising into the atmosphere due to convection, achieving full residual heat removal. The VHTR is scheduled to be prototyped and tested at Idaho National Laboratory within the next decade (as of 2009) as the design selected for the Next Generation Nuclear Plant by the US Department of Energy. This reactor will use a gas as a coolant, which can then be used for process heat (such as in hydrogen production) or for the driving of gas turbines and the generation of electricity. 

A similar highly advanced gas cooled reactor originally designed by West Germany (the AVR reactor) and now developed by South Africa is known as the Pebble Bed Modular Reactor. It is an inherently safe design, meaning that core damage is physically impossible, due to the design of the fuel (spherical graphite "pebbles" arranged in a bed within a metal RPV and filled with TRISO (or QUADRISO) pellets of uranium, thorium, or mixed oxide within). A prototype of a very similar type of reactor has been built by the Chinese, HTR-10, and has worked beyond researchers' expectations, leading the Chinese to announce plans to build a pair of follow-on, full-scale 250 MWe, inherently safe, power production reactors based on the same concept.

Lead and Lead-Bismuth-cooled reactors

Recently it was identified a special phenomenology for heavy liquid metal-cooled fast reactors -HLM, as lead and lead-bismuth-cooled reactors. Because of the similar densities of the fuel and the HLM, an inherent passive safety self-removal feedback mechanism due to buoyancy forces is developed, which propels the packed bed away from the wall when certain threshold of temperature is attained and the bed becomes lighter than the surrounding coolant, thus preventing temperatures that can jeopardize the vessel’s structural integrity and also reducing the recriticality potential by limiting the allowable bed depth.

Experimental or conceptual designs

Some design concepts for nuclear reactors emphasize resistance to meltdown and operating safety.
The PIUS (process inherent ultimate safety) designs, originally engineered by the Swedes in the late 1970s and early 1980s, are LWRs that by virtue of their design are resistant to core damage. No units have ever been built. 

Power reactors, including the Deployable Electrical Energy Reactor, a larger-scale mobile version of the TRIGA for power generation in disaster areas and on military missions, and the TRIGA Power System, a small power plant and heat source for small and remote community use, have been put forward by interested engineers, and share the safety characteristics of the TRIGA due to the uranium zirconium hydride fuel used. 

The Hydrogen Moderated Self-regulating Nuclear Power Module, a reactor that uses uranium hydride as a moderator and fuel, similar in chemistry and safety to the TRIGA, also possesses these extreme safety and stability characteristics, and has attracted a good deal of interest in recent times. 

The liquid fluoride thorium reactor is designed to naturally have its core in a molten state, as a eutectic mix of thorium and fluorine salts. As such, a molten core is reflective of the normal and safe state of operation of this reactor type. In the event the core overheats, a metal plug will melt, and the molten salt core will drain into tanks where it will cool in a non-critical configuration. Since the core is liquid, and already melted, it cannot be damaged.

Advanced liquid metal reactors, such as the U.S. Integral Fast Reactor and the Russian BN-350, BN-600, and BN-800, all have a coolant with very high heat capacity, sodium metal. As such, they can withstand a loss of cooling without SCRAM and a loss of heat sink without SCRAM, qualifying them as inherently safe.

Soviet Union-designed reactors

RBMKs

Soviet-designed RBMK reactors (Reaktor Bolshoy Moshchnosti Kanalnyy), found only in Russia and the CIS and now shut down everywhere except Russia, do not have containment buildings, are naturally unstable (tending to dangerous power fluctuations), and have emergency cooling systems (ECCS) considered grossly inadequate by Western safety standards. The Chernobyl Disaster reactor was an RBMK. 

RBMK ECCS systems only have one division and little redundancy within that division. Though the large core of the RBMK is less energy-dense than the smaller Western LWR core, it is harder to cool. The RBMK is moderated by graphite. In the presence of both steam and oxygen at high temperatures, graphite forms synthesis gas and with the water gas shift reaction, the resultant hydrogen burns explosively. If oxygen contacts hot graphite, it will burn. Control rods used to be tipped with graphite, a material that slows neutrons and thus speeds up the chain reaction. Water is used as a coolant, but not a moderator. If the water boils away, cooling is lost, but moderation continues. This is termed a positive void coefficient of reactivity. 

The RBMK tends towards dangerous power fluctuations. Control rods can become stuck if the reactor suddenly heats up and they are moving. Xenon-135, a neutron absorbent fission product, has a tendency to build up in the core and burn off unpredictably in the event of low power operation. This can lead to inaccurate neutronic and thermal power ratings. 

The RBMK does not have any containment above the core. The only substantial solid barrier above the fuel is the upper part of the core, called the upper biological shield, which is a piece of concrete interpenetrated with control rods and with access holes for refueling while online. Other parts of the RBMK were shielded better than the core itself. Rapid shutdown (SCRAM) takes 10 to 15 seconds. Western reactors take 1 - 2.5 seconds. 

Western aid has been given to provide certain real-time safety monitoring capacities to the operating staff. Whether this extends to automatic initiation of emergency cooling is not known. Training has been provided in safety assessment from Western sources, and Russian reactors have evolved in result to the weaknesses that were in the RBMK. However, numerous RBMKs still operate. 

Though it might be possible to stop a loss-of-coolant event prior to core damage occurring, any core damage incidents will probably allow massive release of radioactive materials. 

Upon entering the EU in 2004, Lithuania was required to phase out its two RBMKs at Ignalina NPP, deemed totally incompatible with European nuclear safety standards. The country plans to replace them with safer reactors.

MKER

The MKER is a modern Russian-engineered channel type reactor that is a distant descendant of the RBMK, designed to optimize the benefits and fix the serious flaws of the original. 

Several unique features of the MKER's design make it a credible and interesting option: The reactor remains online during refueling, ensuring outages only occasionally for maintenance, with uptime up to 97-99%. The moderator design allows the use of less-enriched fuels, with a high burnup rate. Neutronics characteristics have been optimized for civilian use, for superior fuel fertilization and recycling; and graphite moderation achieves better neutronics than is possible with light water moderation. The lower power density of the core greatly enhances thermal regulation. 

An array of improvements make the MKER's safety comparable to Western Generation III reactors: improved quality of parts, advanced computer controls, comprehensive passive emergency core cooling system, and very strong containment structure, along with a negative void coefficient and a fast-acting rapid shutdown system. The passive emergency cooling system uses reliable natural phenomena to cool the core, rather than depending on motor-driven pumps. The containment structure is designed to withstand severe stress and pressure. In the event of a pipe break of a cooling-water channel, the channel can be isolated from the water supply, preventing a general failure. 

The greatly enhanced safety and unique benefits of the MKER design enhance its competitiveness in countries considering full fuel-cycle options for nuclear development.

VVER

The VVER is a pressurized light water reactor that is far more stable and safe than the RBMK. This is because it uses light water as a moderator (rather than graphite), has well understood operating characteristics, and has a negative void coefficient of reactivity. In addition, some have been built with more than marginal containments, some have quality ECCS systems, and some have been upgraded to international standards of control and instrumentation. Present generations of VVERs (the VVER-1000) are built to Western-equivalent levels of instrumentation, control, and containment systems. 

However, even with these positive developments, certain older VVER models raise a high level of concern, especially the VVER-440 V230.

The VVER-440 V230 has no containment building, but only has a structure capable of confining steam surrounding the RPV. This is a volume of thin steel, perhaps an inch or two in thickness, grossly insufficient by Western standards.
  • Has no ECCS. Can survive at most one 4 inch pipe break (there are many pipes greater than 4 inches within the design).
  • Has six steam generator loops, adding unnecessary complexity.
    • However, apparently steam generator loops can be isolated, in the event that a break occurs in one of these loops. The plant can remain operating with one isolated loop - a feature found in few Western reactors.
The interior of the pressure vessel is plain alloy steel, exposed to water. This can lead to rust, if the reactor is exposed to water. One point of distinction in which the VVER surpasses the West is the reactor water cleanup facility - built, no doubt, to deal with the enormous volume of rust within the primary coolant loop - the product of the slow corrosion of the RPV. This model is viewed as having inadequate process control systems. 

Bulgaria had a number of VVER-440 V230 models, but they opted to shut them down upon joining the EU rather than backfit them, and are instead building new VVER-1000 models. Many non-EU states maintain V230 models, including Russia and the CIS. Many of these states - rather than abandoning the reactors entirely - have opted to install an ECCS, develop standard procedures, and install proper instrumentation and control systems. Though confinements cannot be transformed into containments, the risk of a limiting fault resulting in core damage can be greatly reduced.

The VVER-440 V213 model was built to the first set of Soviet nuclear safety standards. It possesses a modest containment building, and the ECCS systems, though not completely to Western standards, are reasonably comprehensive. Many VVER-440 V213 models operated by former Soviet bloc countries have been upgraded to fully automated Western-style instrumentation and control systems, improving safety to Western levels for accident prevention - but not for accident containment, which is of a modest level compared to Western plants. These reactors are regarded as "safe enough" by Western standards to continue operation without major modifications, though most owners have performed major modifications to bring them up to generally equivalent levels of nuclear safety. 

During the 1970s, Finland built two VVER-440 V213 models to Western standards with a large-volume full containment and world-class instrumentation, control standards and an ECCS with multiply redundant and diversified components. In addition, passive safety features such as 900-tonne ice condensers have been installed, making these two units safety-wise the most advanced VVER-440's in the world. 

The VVER-1000 type has a definitely adequate Western-style containment, the ECCS is sufficient by Western standards, and instrumentation and control has been markedly improved to Western 1970s-era levels.

Chernobyl disaster

In the Chernobyl disaster the fuel became non-critical when it melted and flowed away from the graphite moderator - however, it took considerable time to cool. The molten core of Chernobyl (that part that was not blown outside the reactor or did not vaporize in the fire) flowed in a channel created by the structure of its reactor building and froze in place before a core-concrete interaction could happen. In the basement of the reactor at Chernobyl, a large "elephant's foot" of congealed core material was found, one example of the freely-flowing corium. Time delay, and prevention of direct emission to the atmosphere (i.e., containment), would have reduced the radiological release. If the basement of the reactor building had been penetrated, the groundwater would be severely contaminated, and its flow could carry the contamination far afield. 

The Chernobyl reactor was a RBMK type. The disaster was caused by a power excursion that led to a steam explosion, meltdown and extensive offsite consequences. Operator error and a faulty shutdown system led to a sudden, massive spike in the neutron multiplication rate, a sudden decrease in the neutron period, and a consequent increase in neutron population; thus, core heat flux increased rapidly beyond the design limits of the reactor. This caused the water coolant to flash to steam, causing a sudden overpressure within the reactor pressure vessel (RPV), leading to granulation of the upper portion of the core and the ejection of the upper plenum of said pressure vessel along with core debris from the reactor building in a widely dispersed pattern. The lower portion of the reactor remained somewhat intact; the graphite neutron moderator was exposed to oxygen-containing air; heat from the power excursion in addition to residual heat flux from the remaining fuel rods left without coolant induced oxidation in the moderator and in the opened fuel rods; this in turn evolved more heat and contributed to the melting of more of the fuel rods and the outgassing of the fission products contained therein. The liquefied remains of the melted fuel rods, pulverized concrete and any other objects in the path flowed through a drainage pipe into the basement of the reactor building and solidified in a mass, though the primary threat to the public safety was the dispersed core ejecta, vaporized and gaseous fission products and fuel, and the gasses evolved from the oxidation of the moderator. 

Although the Chernobyl accident had dire off-site effects, much of the radioactivity remained within the building. If the building were to fail and dust was to be released into the environment then the release of a given mass of fission products which have aged for almost thirty years would have a smaller effect than the release of the same mass of fission products (in the same chemical and physical form) which had only undergone a short cooling time (such as one hour) after the nuclear reaction has been terminated. However, if a nuclear reaction was to occur again within the Chernobyl plant (for instance if rainwater was to collect and act as a moderator) then the new fission products would have a higher specific activity and thus pose a greater threat if they were released. To prevent a post-accident nuclear reaction, steps have been taken, such as adding neutron poisons to key parts of the basement.

Effects

The effects of a nuclear meltdown depend on the safety features designed into a reactor. A modern reactor is designed both to make a meltdown unlikely, and to contain one should it occur. 

In a modern reactor, a nuclear meltdown, whether partial or total, should be contained inside the reactor's containment structure. Thus (assuming that no other major disasters occur) while the meltdown will severely damage the reactor itself, possibly contaminating the whole structure with highly radioactive material, a meltdown alone should not lead to significant radioactivity release or danger to the public.

A nuclear meltdown may be part of a chain of disasters. For example, in the Chernobyl accident, by the time the core melted, there had already been a large steam explosion and graphite fire, and a major release of radioactive contamination. Prior to a meltdown, operators may reduce pressure in the reactor by releasing radioactive steam to the environment. This would allow fresh cooling water to be injected with the intent of preventing a meltdown.

Reactor design

Although pressurized water reactors are more susceptible to nuclear meltdown in the absence of active safety measures, this is not a universal feature of civilian nuclear reactors. Much of the research in civilian nuclear reactors is for designs with passive nuclear safety features that may be less susceptible to meltdown, even if all emergency systems failed. For example, pebble bed reactors are designed so that complete loss of coolant for an indefinite period does not result in the reactor overheating. The General Electric ESBWR and Westinghouse AP1000 have passively activated safety systems. The CANDU reactor has two low-temperature and low-pressure water systems surrounding the fuel (i.e. moderator and shield tank) that act as back-up heat sinks and preclude meltdowns and core-breaching scenarios. Liquid fueled reactors can be stopped by draining the fuel into tankage which not only prevents further fission but draws decay heat away statically, and by drawing off the fission products (which are the source of post-shutdown heating) incrementally. The ideal is to have reactors that fail-safe through physics rather than through redundant safety systems or human intervention. 

Certain fast breeder reactor designs may be more susceptible to meltdown than other reactor types, due to their larger quantity of fissile material and the higher neutron flux inside the reactor core. However, reactor designs such as Integral Fast Reactor model EBR II, had been explicitly engineered to be meltdown-immune. It was tested in April 1986, just before the Chernobyl failure, to simulate loss of coolant pumping power, by switching off the power to the primary pumps. As designed, it shut itself down, in about 300 seconds, as soon as the temperature rose to a point designed as higher than proper operation would require. This was well below the boiling point of the unpressurized liquid metal coolant, which had entirely sufficient cooling ability to deal with the heat of fission product radioactivity, by simple convection. The second test, deliberate shut-off of the secondary coolant loop that supplies the generators, caused the primary circuit to undergo the same safe shutdown. This test simulated the case of a water-cooled reactor losing its steam turbine circuit, perhaps by a leak.

Nuclear meltdown events

This is a list of the major reactor failures in which meltdown played a role:

United States

SL-1 core damage after a nuclear excursion.
  • BORAX-I was a test reactor designed to explore criticality excursions and observe if a reactor would self limit. In the final test, it was deliberately destroyed and revealed that the reactor reached much higher temperatures than were predicted at the time.
  • The reactor at EBR-I suffered a partial meltdown during a coolant flow test on 29 November 1955.
  • The Sodium Reactor Experiment in Santa Susana Field Laboratory was an experimental nuclear reactor which operated from 1957 to 1964 and was the first commercial power plant in the world to experience a core meltdown in July 1959.
  • Stationary Low-Power Reactor Number One (SL-1) was a United States Army experimental nuclear power reactor which underwent a criticality excursion, a steam explosion, and a meltdown on 3 January 1961, killing three operators.
  • The SNAP8ER reactor at the Santa Susana Field Laboratory experienced damage to 80% of its fuel in an accident in 1964.
  • The partial meltdown at the Fermi 1 experimental fast breeder reactor, in 1966, required the reactor to be repaired, though it never achieved full operation afterward.
  • The SNAP8DR reactor at the Santa Susana Field Laboratory experienced damage to approximately a third of its fuel in an accident in 1969.
  • The Three Mile Island accident, in 1979, referred to in the press as a "partial core melt" led to the total dismantlement and the permanent shutdown of that reactor. Unit-1 still continues to operate at TMI.

Soviet Union

Japan

Switzerland

Canada

United Kingdom

France

Czechoslovakia

China syndrome

The China syndrome (loss-of-coolant accident) is a hypothetical nuclear reactor operations accident characterized by the severe meltdown of the core components of the reactor, which then burn through the containment vessel and the housing building, then (figuratively) through the crust and body of the Earth until reaching the opposite side (which, in the United States, is colloquially referred to as China). The phrasing is metaphorical; there is no way a core could penetrate the several-kilometer thickness of the Earth's crust, and even if it did melt to the center of the Earth, it would not travel back upwards against the pull of gravity. Moreover, any tunnel behind the material would be closed by immense lithostatic pressure. Furthermore, China does not contain the antipode of any landmass in North America. 

In reality, under a complete loss of coolant scenario, the fast erosion phase of the concrete basement lasts for about an hour and progresses into about one meter depth, then slows to several centimeters per hour, and stops completely when the corium melt cools below the decomposition temperature of concrete (about 1,100 °C). Complete melt-through can occur in several days, even through several meters of concrete; the corium then penetrates several meters into the underlying soil, spreads around, cools, and solidifies. It is also possible that there is already a harmless dense natural concentration of radioactive material in the Earth's core (primarily uranium-238, thorium-232 and potassium-40, which have half-lives of 4.47 billion years, 14.05 billion years and 1.25 billion years respectively.)

The real scare, however, came from a quote in the 1979 film The China Syndrome, which stated, "It melts right down through the bottom of the plant—theoretically to China, but of course, as soon as it hits ground water, it blasts into the atmosphere and sends out clouds of radioactivity. The number of people killed would depend on which way the wind was blowing, rendering an area the size of Pennsylvania permanently uninhabitable." The actual threat of this was tested just 12 days after the release of the film when a meltdown at Pennsylvania's Three Mile Island Plant 2 (TMI-2) created a molten core that moved 15 millimeters toward "China" before the core froze at the bottom of the reactor pressure vessel. Thus, the TMI-2 reactor fuel and fission products breached the fuel plates, but the melted core itself did not break the containment of the reactor vessel. Hours after the meltdown, concern about hydrogen build-up led operators to release some radioactive gasses into the atmosphere, including gaseous fission products. Release of the fission products led to a temporary evacuation of the surrounding area, but no injuries. 

A similar concern arose during the Chernobyl disaster: after the reactor was destroyed, a liquid corium mass from the melting core began to breach the concrete floor of the reactor vessel, which was situated above the bubbler pool (a large water reservoir for emergency pumps, also designed to safely contain steam pipe ruptures). The RBMK had no allowance or planning for core meltdowns, and the imminent interaction of the core mass with the bubbler pool would have produced a considerable steam explosion, increasing the spread and magnitude of the radioactive plume. It was therefore necessary to drain the bubbler pool before the corium reached it. However, the initial explosion had broken the control circuitry which allowed the pool to be emptied. Three station workers volunteered to go manually operate the valves necessary to drain this pool, and later images of the corium mass in the pipes of the bubbler pool's basement reinforced the prudence of their actions.

History

The system design of the nuclear power plants built in the late 1960s raised questions of operational safety, and raised the concern that a severe reactor accident could release large quantities of radioactive materials into the atmosphere and environment. By 1970, there were doubts about the ability of the emergency core cooling system of a nuclear reactor to prevent a loss of coolant accident and the consequent meltdown of the fuel core; the subject proved popular in the technical and the popular presses. In 1971, in the article Thoughts on Nuclear Plumbing, former Manhattan Project (1942–1946) nuclear physicist Ralph Lapp used the term "China syndrome" to describe a possible burn-through, after a loss of coolant accident, of the nuclear fuel rods and core components melting the containment structures, and the subsequent escape of radioactive material(s) into the atmosphere and environment; the hypothesis derived from a 1967 report by a group of nuclear physicists, headed by W. K. Ergen. In the event, Lapp’s hypothetical nuclear accident was cinematically adapted as The China Syndrome (1979).

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