Nuclear power plants
Nuclear reactors. General

Today's nuclear technologies make varying degrees of use of natural resources in fissile materials (²³⁵U) and fertile materials (²³⁸U and ²³²Th) capable of producing fissile materials (²³⁹Pu, ²³³U) by neutron absorption. They also produce more or less minor actinides (isotopes of Np, Am and Cm), radionuclides that are more or less long-lived, radiotoxic and, in the case of those with shorter half-lives, non-negligible sources of heat in the waste. Waste streams can be classified according to their characteristics in these two areas, distinguishing between uranium and thorium streams.

Uranium technologies that use plutonium can be classified into three families (Box 2).