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About Uranium

Nuclear Power

Nuclear energy supplies around 14% of the world's electricity, more than the world used from all sources in 1960.  Today 30 countries use nuclear energy to generate up to three quarters of their electricity, and a substantial number of these depend on it for one quarter to one half of their supply. In Europe and Japan, the nuclear share of electricity is over 30%. In the U.S., nuclear power creates 20% of electricity.

Some 14,000 reactor years of operational experience have been accumulated since the 1950s by the world's 440 nuclear power reactors. More than half of the world’s population lives in nations where nuclear power plants are an integral part of electricity production and industrial infrastructures Half the world's people live in countries where new nuclear power reactors are in planning or under construction. Thus, a rapid expansion of global nuclear power would require no fundamental change - simply an acceleration of existing strategies.

Around the world, scientists in more than 50 countries use nearly 300 research reactors to investigate nuclear technologies and to produce radioisotopes for medical diagnosis and cancer therapy. Meanwhile, on the world's oceans, nuclear reactors have powered over 400 ships without harm to crews or the environment.

In the Cold War's aftermath, a key activity is the removal of nuclear material from weapons and its conversion to fuel for civil nuclear power.

Many countries have a strong commitment to nuclear power. Among these are China, India, the United States, Russia and Japan, which together represent half of world population. Other nations - such as Argentina, Brazil, Canada, Finland, South Korea, South Africa, Ukraine, the United Kingdom and several other countries in Central and Eastern Europe - are acting to increase the role of nuclear power in their economies. Key developing nations without nuclear power - such as Indonesia, Egypt and Vietnam - are considering this option.

Nuclear power provides energy independence and security of supply. France, with 60 million people, obtains over 75% of its electricity from nuclear power and is the world's largest net exporter of electricity. Italy's 60 million people have no nuclear power and are the world's largest importers of electricity, much of it generated by nuclear power plants.


Uranium occurs in most rocks in concentrations of 2 to 4 parts per million and is as common in the earth's crust as tin, tungsten and molybdenum. It occurs in seawater, and could be recovered from the oceans if prices rose significantly.  It was discovered in 1789 by Martin Klaproth, a German chemist, in the mineral called pitchblende. It was named after the planet Uranus, which had been discovered eight years earlier.

Like other elements, uranium occurs in slightly differing forms known as 'isotopes'. These isotopes (16 in the case of uranium) differ from each other in the number of particles (neutrons) in the nucleus. 'Natural' uranium as found in the earth's crust is a mixture largely of two isotopes: uranium-238 (U-238), accounting for 99.3% and U-235 about 0.7%.

The isotope U-235 is important because under certain conditions it can readily be split, yielding a lot of energy. It is therefore said to be 'fissile' and we use the expression 'nuclear fission'

The nucleus of the U-235 atom comprises 92 protons and 143 neutrons (92 + 143 = 235). When the nucleus of a U-235 atom captures a neutron it splits in two (fissions) and releases some energy in the form of heat, also two or three additional neutrons are thrown off. If enough of these expelled neutrons cause the nuclei of other U-235 atoms to split, releasing further neutrons, a fission reaction can be achieved. When this happens over and over again, many millions of times, a very large amount of heat is produced from a relatively small amount of uranium.

It is this process, in effect "burning" uranium, which occurs in a nuclear reactor. The heat is used to make steam to produce electricity.