The steam turns a turbine to generate electricity. Another nuclear process could also yield energy. Nuclear fusion takes place when two hydrogen atoms join together to form a larger helium atom. The helium atom is not quite as heavy as the two hydrogen atoms were. The lost mass is converted into energy.
Nuclear fusion is the process that makes the sun burn.
People have not been able to recreate fusion on Earth yet, except in very brief tests. Researchers are still studying ways to do this. Some special features of nuclear energy Nuclear power plants use uranium as fuel because uranium atoms are fairly easy to split. The fuel and its waste products are radioactive. They give off a kind of energy called radiation that can be harmful to living things.