Being the power source that determines the underwater lifetime of nuclear reactors

The difference between a nuclear-powered submarine and a conventional submarine is the power generation system. Nuclear submarines use nuclear reactors to generate power. One produces electricity to power the ship’s electric motors, while the other uses the heat generated by the reactor to produce steam power to drive the turbines. The reactors used in submarines typically use highly enriched fuel (in concentrations of more than 20%) to provide high power output from a small reactor.

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