| Nuclear power is the controlled use of | | | | Creating various radioactive isotopes, such |
| nuclear reactions to release energy for work | | | | as americium for use in smoke detectors, and |
| including propulsion, heat, and the | | | | cobalt-60, molybdenum-99 and others, used for |
| generation of electricity. Use of nuclear | | | | imaging and medical treatment |
| power to do significant useful work is | | | | |
| currently limited to nuclear fission and | | | | Research applications including: |
| radioactive decay. Nuclear energy is produced | | | | |
| when a fissile material, such as uranium-235. | | | | Providing a source of neutron and positron |
| (235U), is concentrated such that nuclear | | | | radiation (e.g. Neutron activation analysis |
| fission takes place in a controlled chain | | | | and Potassium-argon dating) |
| reaction and creates heat — which is | | | | |
| used to boil water, produce steam, and drive | | | | Development of nuclear technology |
| a steam turbine. The turbine can be used for | | | | |
| mechanical work and also to generate | | | | The United States produces the most nuclear |
| electricity. Nuclear power provides 7% of the | | | | energy, with nuclear power providing 20% of |
| world's energy and 15.7% of the world's | | | | the electricity it consumes, while France |
| electricity and is used to power most | | | | produces the highest percentage of its |
| military submarines and aircraft carriers.[1] | | | | electrical energy from nuclear |
| | | | reactors—80% as of 2006. In the |
| Disquiet over the safety of nuclear power was | | | | European Union as a whole, nuclear energy |
| exacerbated by the unsafe design and | | | | provides 30% of the electricity. Nuclear |
| operation of the Soviet-built plant at | | | | energy policy differs between countries, and |
| Chernobyl. However, new plants designed to be | | | | some countries such as Austria and Ireland |
| safer than current Western plants are on the | | | | have no active nuclear power stations. |
| verge of being built - and global warming | | | | |
| concerns may spark a resurgence. Controversy | | | | As of 2007, the IAEA reported there are 435 |
| remains (see Nuclear energy policy). | | | | nuclear power reactors in operation in the |
| | | | world , operating in 31 different countries . |
| Use | | | | Together, they produce about 17% of the |
| | | | world's electric power. The U.S., France, and |
| Power: | | | | Japan together account for 49% of all nuclear |
| | | | power plants and 57% of all nuclear generated |
| Heat for electricity generation | | | | electricity. |
| | | | |
| Heat for domestic and industrial heating | | | | International research is ongoing into |
| | | | various safety improvements, the use of |
| Hydrogen production | | | | nuclear fusion and additional uses such as |
| | | | the generation of hydrogen (in support of |
| Desalination | | | | hydrogen economy schemes), for desalinating |
| | | | sea water, and for use in district heating |
| Nuclear propulsion: | | | | systems. Lately, there has been renewed |
| | | | interest in nuclear energy from national |
| Nuclear marine propulsion | | | | governments due to energy security and |
| | | | climate change. Other reasons for interest |
| Proposed nuclear thermal rockets | | | | include the public, some notable |
| | | | environmentalists due to increased oil |
| Proposed nuclear pulse propulsion rockets | | | | prices, new passively safe designs of plants. |
| | | | The low emission rate of greenhouse gas which |
| Transmutation of elements: | | | | all countries, excluding the US and |
| | | | Australia, need to meet the standards of the |
| Production of plutonium, often for use in | | | | Kyoto Protocol. A few reactors are under |
| nuclear weapons | | | | construction, and several new types of |
| | | | reactors are planned. |