Nuclear energy light water reactors

ISO (1992) Nuclear energy - Light water reactors Calculation of the decay heat power in nuclear fuels, ISO 10645. 

In the current structure of nuclear power, light water reactors (LWRs) are predominant over a small number of heavy water reactors (HWRs), and even smaller number of fast breeder reactors (FBRs). However, an increase of FBR share can be predicted for the future, taking into account their unique properties. First of all, there is the capability of nuclear fuel breeding by involving into the fuel cycle. Secondly, there is the fast reactor s flexibility permitting its use as plutonium incinerators and minor actinides transmutation. Thus, unless new sources of energy are found, the development of nuclear power will be necessarily based on fast breeder reactors. 

LDH LEU LIBD LAW LET LILW LIP LLNL LLW LMA LMFBR LOI LREE L/S LTA LWR Layered double hydroxide Low enriched uranium Laser-induced breakdown detection Low-activity waste Linear energy transfer Low- and intermediate-level nuclear waste Lead-iron phosphate Lawrence Livermore National Laboratory Low-level nuclear waste Law of mass action Liquid-metal-cooled fast-breeder reactor Loss on ignition Light rare earth elements (La-Sm) Liquid-to-solid ratio (leachates) Low-temperature ashing Light water reactor... 

Advanced Proliferation Resistant, Lower Cost, Uranium-Thorium Dioxide Fuels for Light Water Reactors, Nuclear Energy Research Initiative, Idaho National Engineering and Environmental Laboratory, Idaho Falls, ID, 2000. 

The United States derived about 20 percent of its electricity from nuclear energy in 2002 (EIA, Electric Power Monthly, 2003). The 103 power reactors operating today have a total capacity of nearly 100 gigawatts electric (GWe) and constitute about 13 percent of the installed U.S. electric generation capacity. The current U.S. plants use water as the coolant and neutron moderator (hence called light-water reactors, or LWRs) and rely on the steam Rankine cycle as the thermal-to-electrical power conversion cycle. Other countries use other technologies—notably C02-cooled reactors in the United Kingdom and heavy-water-cooled reactors (HWRs) in Canada and India. 

Electricity generated at nuclear power stations presently accoimts for some 8.4 EJ y or 2% of global energy use (USDoE, 2003). The technology used is primarily light water reactors, a commercial spin-off from the submarine nuclear-powered propulsion systems introduced in the 1950s. The situation after World War II was characterised by two factors of some importance for the development of nuclear energy and the specific reactor choice ... 

The projections are based on a recent forecast (Case B) by the Energy Research and Development Administration (ERDA) of nuclear power growth in the United States (2) and on fuel mass-flow data developed for light water reactors fueled with uranium (LWR-U) or mixed uranium and plutonium oxide (LWR-Pu), a high temperature gas-cooled reactor (HTGR), and two liquid-metal-cooled fast breeder reactors (LMFBRs). Nuclear characteristics of the fuels and wastes were calculated using the computer code ORIGEN (3). 

With regard to the heat market, a light-water reactor (LWR) of the 1200 - 1400 MW(e) class has the potential to provide 10,000 GJ/h of low-temperature heat ( 320 °C) in the CHP mode. Since hot water and process steam cannot be transported directly over long distances, nuclear power can be economically used only in areas with large heat consumption density like chemical industrial complexes, or in long-distance heating systems where some of the candidate chemical energy transmission systems can be operated at lower temperatures. 

In conclusion, the nuclear properties of thorium can be a source of vast energy production. As demonstrated by the Light Water Breeder Reactor Program, this production can be achieved in nuclear reactors utilizing proven light water reactor technology. 

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