History of nuclear power : the United States : Life History

History of nuclear power : the United States : Life History 

 We begin in 1896. In Paris, physicist Henri Becquerel accidentallydiscovers during an experiment that uranium leaves a trace -- or darkens -- a photographic plate without any other light source. He concludes that uranium naturally emitsa ray he calls “uranique” in French. In the following years, physicists Pierreand Marie Curie discover other elements that also naturally emit radiation. They call the phenomenon radioactivity. Later, Ernest Rutherford, a British physicistborn in New Zealand, suggests that radioactivity is radiation that accompanies the disintegration of atoms, which were previously considered to be indestructible. 

Other findings are then used to better understandthe structure of the atom, with electrons revolving around a nucleus composed of protons and neutrons. In 1938, two German chemists, Hahn and Strassmanndiscover nuclear fission. Bombarding an atom of uranium with a neutron,it is divided into two, releasing energy. 

The following year in Paris, Frédéric Joliot-Curiediscovers that during the nuclear fission of uranium, three neutrons are ejected whichin turn could cause further fission of atoms. He discovers the ability to initiate a chainreaction and thus produce a large amount of energy. In Europe, World War II breaks out.

 While Germany continues to conduct researchon uranium, Albert Einstein is convinced by Hungarian physicists to sign a letter addressed to Roosevelt, the President of the United States informing him of recent nuclear discoveries and the possibility of creating a very powerful bomb using uranium. The United States benefits from the influxof European scientists fleeing war and invests in research. 

At the University of California, Glenn Seaborgdiscovers that irradiated uranium produces a tiny amount of plutonium, a new metal that is radioactive and fissile, i.e. it can trigger a chain reaction. In Chicago, Enrico Fermi creates the firstatomic pile and - for the first time - manages to control the first chain reaction of thefission of uranium atoms. Research is accelerated and substantial resourcesare invested. The United States secretly launches the Manhattan Project in collaboration with Canada and the United Kingdom. 

Top scientists gather in about 30 secret locations, with the best laboratories at the time made available to them. Their goal is to create the atomic bomb. The goal is to create a bomb from uraniumand another from plutonium. In nature, uranium is composed of more than99% of Uranium 238, i.e. with a nucleus of 92 protons and 146 neutrons, and 0.7% of Uranium235, with three neutrons less. Only the latter is fissile and therefore usefulin the project. The challenge is isolating and concentratingit to obtain so-called enriched uranium. 

The United States manages to produce 64 tonsof highly enriched uranium to be used in the manufacture of the first bomb. By propelling a highly enriched uranium blockonto another, the material becomes supercritical. Fission begins and in a split second, a chain reaction ensues, releasing tremendous amounts of energy. For a plutonium bomb, a maximum of uranium piles are created in order to collect the plutonium produced.

 A few pounds are concentrated in the centerof the bomb. By simultaneously causing explosions all around, the material is compressed, becomes supercritical and explodes. On 16 July 1945, the first successful nucleartest takes place in the desert of New Mexico. By this point, Germany had already surrendered. Only the Empire of Japan is still at war againstthe United States. After Japan refuses to surrender unconditionally, the United States drops two atomic bombs on the country a uranium bomb on Hiroshimaand a plutonium one on Nagasaki. The two bombs cause about 200,000 civiliancasualties. Days later, Japan surrenders. With the United States demonstrating its powerto the world, the USSR accelerates its own nuclear program to try and catch up. 

The USSR conducts its first nuclear test. During the Cold War, both powers engage in a frantic arms race. Large sums are spent to gain technological superiority and possess the world’s largest nuclear arsenal with the ostensible aim ofdeterring the enemy from attacking. While the United Kingdom tests its first atomic bomb, the United States tests its first thermonuclear bomb, also known as the hydrogen or H-bomb. This is a fusion bomb, i.e. it reproduces the reaction occurring in stars by fusing two light atoms, deuterium and tritium, under high pressure and a temperature of several million degrees Celsius. 

To achieve these conditions, it is decidedto use the atomic bomb as a trigger. The explosion of the plutonium bomb createsthe right conditions to trigger the fusion of atoms. The explosion that follows is far more powerfulthan nuclear fission. The Soviets, in turn, develop the H-bomb. In parallel, research is made to develop nuclear power. The first nuclear power plants appear. The majority of future reactors would be withpressurized water. In the core of the reactor is a vessel inwhich low-enriched uranium is placed and used as fuel. Chain reactions are controlled to last about3 years.

 The heat emitted increases the temperatureof pressurized water in the primary circuit. This circuit is brought into contact with the secondary circuit in which water heats to transform into steam. This is used to rotate the turbine which islinked to a generator that produces electricity. A cooling circuit pumps water from a riveror sea to cool the vapor in the secondary circuit. Sometimes cooling towers are built to coolthe water in the last circuit. To encourage research in nuclear power, the International Atomic Energy Agency (IAEA) is created under the aegis of the United Nations.

 The organization is responsible for ensuringthe safe and peaceful use of nuclear energy. In addition, nuclear would also be used inmedicine, notably in medical imaging and the treatment of certain cancers. While France tests its first atomic bomb, the arms race between the USSR and the United States takes a turn for the worse. The two powers have already developed intercontinental missiles and nuclear submarines. The USSR conducts the most powerful test of the Tsar Bomba, with a capacity of 50 to 57 megatons of TNT. The following year, 

the US tests a hydrogenbomb at an altitude of 400 km. The explosion creates an artificial auroravisible even from New Zealand; while the emitted radiation damages at least 8 satellites. The same year, while the United States threatensSoviet territories with nuclear missiles installed in Turkey and Italy, the USSR placesin Cuba nuclear missiles pointed at the United States. Just as tensions build to a climax, negotiationstake place between the two powers after which both parties withdraw their missiles and thesituation calms down. China tests its first atomic bomb.

 The United States and Soviet Union takes adim view of the arrival of new competitors. Via the UN, they propose a Treaty on the Non-Proliferation of Nuclear Weapons. This differentiates the 5 so-called nuclearpowers from the rest of the world. Existing nuclear powers cannot share knowledgeor supply weapons, while remaining countries cannot attempt to obtain the atomic bomb. In addition, nuclear powers are supposed todisarm as much as possible. 

This treaty would gradually be signed by allcountries of the world with the exception of India, Pakistan and Israel, which denies having atomic weapons despite heavy suspicion of the contrary. Latin America goes further by creating thefirst populated area free of nuclear weapons. Finally, the United States and Soviet Unionagree to limit the production of strategic weapons. 1973 sees the world’s first oil crisis. In a short time, the price of a barrel ofoil explodes, undermining global powers whose economy largely depends on the black gold. The world looks for alternatives to ensuretheir energy supply. France and Japan mainly rely on nuclear energy. In the following years, many power plantswould be built around the world.

 In India, a so-called “peaceful” nuclear test takes place, worrying its Pakistani rival which in turn embarks on nuclear research. In 1979, a major nuclear accident takes placein the United States.

 One of the reactors at the Three Mile Island nuclear power plant surges and the primary circuit leaks. As the fuel is no longer submerged, it over heatsand then melts in its vessel. Fortunately, the containment resists and preventsradioactive leaks. A few years later at the Chernobyl nuclear power plant, after a series of human errors, technicians lose control of the reactor. When the temperature of its core becomes toohigh, an explosion blows up the concrete roof, part of which falls and fractures the vessel. A highly radioactive cloud is released intothe air. It spreads and contaminates a large part ofthe European continent. Around the power plant, a 2,600 sq km exclusion zone is created and more than 200,000 people are displaced.

 Around the world, the accidents generate orstrengthen popular opposition to nuclear power, which puts a heavy brake on the developmentof the industry. After the fall of the USSR and the end ofthe Cold War, the US and Russia continue to reduce their nuclear arsenals. In addition, after more than 2,000 officialnuclear tests in the world, the Comprehensive Nuclear-Test-Ban Treaty (CTBT) is introduced. It does not enter into force because out ofthe 44 countries with nuclear reactors at the time, three do not sign it and five otherssign but do not ratify it. 

Two years later, India and Pakistan conducta series of nuclear tests. Abdul Qadeer Khan, considered the father ofthe Pakistani atomic bomb, acknowledges having developed a clandestine network originatingin Dubai, which has been providing Libya, Iran and North Korea with the plans and materialsnecessary to create an atomic bomb. North Korea, after withdrawing from the Treatyon the non-proliferation of nuclear weapons, now declares that it has carried out its firstnuclear test. At the same time, Iran announces that it hassuccessfully enriched uranium, which worries the international community. Israel for its part maintains ambiguity overits nuclear program. Many believe the country has dozens of atomicweapons, but the latter neither confirms nor denies reports to deter any potential enemy. 

One of the advantages of nuclear power isthat it emits little CO2. However, it generates radioactive waste witha lifespan of up to several hundred thousand years. While most of the waste has a lifespan ofa few decades, current technologies do not offer a definitive solution for high-level, long-lived waste. Most countries rely on deep geological repositoriesto store nuclear waste more than 300 meters under the Earth’s surface. On 11 March, 2011, Japan suffers a tripledisaster. 

After an 9.1-magnitude earthquake -- the mostviolent ever recorded in the country -- its coasts are hit by a powerful tsunami with a height of over 10 meters, affecting the Fukushima nuclear plant. Crashes prevent the cooling of the core ofits reactors. Within days, 4 reactors explode, releasinga highly radioactive cloud that is blown towards the Pacific Ocean, reaching the North American continent and then spreading throughout the northern hemisphere. 

All 39 Japanese nuclear reactors are then shutdown. In the aftermath, Germany announces a phasingout of nuclear power. Elsewhere, most nuclear countries review thesafety of their plants. While 9 countries still have 16,000 nuclear bombs, at the UN, a Treaty on the Prohibition of Nuclear Weapons, which aims at the complete elimination of nuclear weapons, is voted by 122 countries. Only the Netherlands votes against, whileSingapore abstains. But the vote is marked above all by the absenceof many countries, including the nuclear powers and member countries of NATO. If the treaty is ratified by 50 countries,it will come into force. Today, 34 countries have already ratifiedit. In terms of nuclear power, 417 operating reactorsproduce just over 10% of the world's electricity. 46 reactors are under construction, including10 in China whose energy needs are increasing. Elsewhere in the world, the nuclear fleetis ageing. Two thirds of global reactors are older than 30 years, out of their originally planned lifespan of 40 years.

 Their future dismantling promises to be costly. New generations of nuclear power plants struggleto meet the world’s rising energy needs, while its construction suffers significantdelays and additional costs. Meanwhile, 35 countries are collaborating around the International Thermonuclear Experimental Reactor, which is being carried outin France. The aim is to study the possibility of buildingnuclear fusion power plants over the long term. Its budget has already jumped from 5 to 19billion euros, but if the project is successful it could offer a new type of power plant thatwould produce a large amount of electricity with little raw material and very little radioactivewaste. 

...........................Life History........................