Light water reactor

Light water reactor (LWR, English Light Water Reactor ) is called a nuclear reactor, in which so-called light water is used as coolant and moderator. " Light Water " denotes ordinary water, whose hydrogen atoms predominantly Protium, the lightest hydrogen isotope are.

The atomic nuclei of light hydrogen ( protons) tend to capture neutrons. Therefore, a larger in comparison to heavy water reactors reactor volume and a higher content of the isotope uranium -235 in nuclear fuel is necessary. The degree of enrichment of uranium must be about 3 to 4%; with natural uranium ( 0.7 % U -235 and 99.3 % uranium -238 ) is a light water reactor is not critical.

The term light water reactor is almost always a power reactor, that meant a plant for the production of electricity. There are two basic types of light water reactor: the pressurized water reactor and boiling water reactor. Your nuclear fuel has almost always oxide form, either pure uranium oxide or uranium -plutonium mixed oxide. However, light water is used in many research reactors as a moderator and coolant.

The first nuclear power plant with boiling water reactor was the world's U.S. plant 24 MW Vallecitos, built and operated by General Electric, 1957., The first nuclear power plant with pressurized water reactor, the U.S. plant 68 MW Shippingport, built by Westinghouse was in succession to the underground world boot reactor, 1958., the world's first large-scale nuclear power plant with pressurized water reactor of 1300 MW class was the German nuclear power plant Biblis A, built by Kraftwerk Union AG (KWU ), 1975.

• Type of reactor