Other nuclear reactors
In addition to commercial nuclear power plants, there are about 240 research reactors operating, in 56 countries, with more under construction. These have many uses including research and the production of medical and industrial isotopes, as well as for training.
The use of reactors for marine propulsion is mostly confined to the major navies where it has played an important role for five decades, providing power for submarines and large surface vessels. About 150 ships are propelled by some 180 nuclear reactors and over 13,000 reactor-years of experience has been gained with marine reactors. Russia and the USA have decommissioned many of their nuclear submarines from the Cold War era.
Russia also operates a fleet of six large nuclear-powered icebreakers and a 62,000 tonne cargo ship which are more civil than military. It is also completing a floating nuclear power plant with two 40 MWe reactors for use in remote regions.