The main nuclear fuels are uranium and plutonium, both of which are radioactive metals. Nuclear fuels are not burnt to release energy. Instead, they are involved in nuclear reactions in the nuclear reactor which leads to heat being released.
Just as with ordinary power stations, the heat energy is used to boil water. The kinetic energy in the expanding steam spins turbines, which drive generators to produce electricity.
Unlike fossil fuels, nuclear fuels do not produce carbon dioxide.
Like fossil fuels, nuclear fuels are non-renewable energy resources. And if there is an accident large amounts of radioactive material could be released into the environment. In addition, nuclear waste remains radioactive and is hazardous to health for thousands of years. It must be stored safely.
Nuclear waste is given different categories:
[ This page has been adapted from www.bbc.co.uk/schools/gcsebitesize/science