Nuclear power From Wikipedia, the free encyclopedia Jump to: navigation, search This page is semi-protected. This article is about applications as a power source. For the underlying energy itself, see Nuclear energy. A nuclear power station. Condensed water vapor rises from the hyperboloid shaped cooling towers. The nuclear reactors are inside the cylindrical containment buildings. A nuclear power station. Condensed water vapor rises from the hyperboloid shaped cooling towers. The nuclear reactors are inside the cylindrical containment buildings. Portal:Nuclear technology Nuclear technology Portal Portal:Energy Energy Portal

Nuclear power is the controlled use of nuclear reactions to release energy for work including propulsion, heat, and the generation of electricity. Human use of nuclear power to do significant useful work is currently limited to nuclear fission and radioactive decay. Nuclear energy is produced when a fissile material, such as uranium-235 (235U), is concentrated such that nuclear fission takes place in a controlled chain reaction and creates heat - which is used to boil water, produce steam, and drive a steam turbine. The turbine can be used for mechanical work and also to generate electricity. Nuclear power is used to power most military submarines and aircraft carriers and provides 7% of the world's energy and 15.7% of the world's electricity.[1] Contents [hide]

* 1 Use * 2 History o 2.1 Origins o 2.2 Early years o 2.3 Development * 3 Reactor types o 3.1 Current technology o 3.2 How it works o 3.3 Experimental technologies * 4 Life cycle o 4.1 Fuel resources o 4.2 Solid waste o 4.3 Reprocessing * 5 Economy o 5.1 Capital costs o 5.2 Operating costs o 5.3 Subsidies o 5.4 Other economic issues * 6 Concerns about nuclear power o 6.1 Accident or attack o 6.2 Health effects on populations o 6.3 Nuclear proliferation * 7 Environmental effects o 7.1 Air pollution o 7.2 Waste heat in water systems * 8 List of atomic energy groups * 9 References * 10 See also o 10.1 Nuclear power by country o 10.2 USAEC/USNRC studies of risk * 11 External links

Use

See also: Nuclear power by country

The United States produces the most nuclear energy, with nuclear power providing 20% of the electricity it consumes, while France produces the highest percentage of its electrical energy from nuclear reactors-80% as of 2006.[2][3] In the European Union as a whole, nuclear energy provides 30% of the electricity.[4] Nuclear energy policy differs between countries.

Nuclear energy uses an abundant, widely distributed fuel, and mitigates the greenhouse effect if used to replace fossil-fuel-derived electricity. International research is ongoing into various safety improvements, the use of nuclear fusion and additional uses such as the generation of hydrogen (in support of hydrogen economy schemes), for desalinating sea water, and for use in district heating systems. Lately, there has been renewed interest in nuclear energy from national governments due to energy security and environmental concerns. Other reasons for interest include the public, some notable environmentalists due to increased oil prices, new passively safe designs of plants, and the low emission rate of greenhouse gas which some governments need to meet the standards of the Kyoto Protocol. A few reactors are under construction, and several new types of reactors are planned.

The use of nuclear power is controversial because of the problem of storing radioactive waste for indefinite periods, the potential for possibly severe radioactive contamination by accident or sabotage, and the possibility that its use in some countries could lead to the proliferation of nuclear weapons. Proponents believe that these risks are small and can be further reduced by the technology in the new reactors. They further claim that the safety record is already good when compared to other fossil-fuel plants, that it releases much less radioactive waste than coal power, and that nuclear power is a sustainable energy source. Critics, including most major environmental groups, believe nuclear power is an uneconomic, unsound and potentially dangerous energy source, especially compared to renewable energy, and dispute whether the costs and risks can be reduced through new technology. There is concern in some countries over North Korea and Iran operating research reactors and fuel enrichment plants, since those countries refuse adequate IAEA oversight and are believed to be trying to develop nuclear weapons. North Korea admits that it is developing nuclear weapons, while the Iranian government vehemently denies the claims against Iran.