Nuclear power stations. Oskarshamn 1 and 2 nuclear power stations. These stations use boiling water reactors (BWR). A BWR is a design in which water is used as both the coolant and the moderator. The moderator slows down the neutrons emitted by nuclear fission, in order to sustain a chain reaction. The water boils in the reactor core and the resulting steam is used to drive a turbine, generating electricity. The combined output of these two reactors is over 1000 megawatts. Photographed in Sweden.