Fission process that leads to generation of electricity
Enriched uranium gives off energy through nuclear fission.
A nuclear power station, big enough to power a city of a million people, consumes just 3 kg of uranium a day. So it is by far the most concentrated and cheap source of energy used by man.
A tiny push caused by neutrons divide the uranium nucleus. And when a nucleus splits, it releases huge amounts of energy, in a process called 'nuclear fission'. During this process, at least two extra neutrons are produced, which fly off and cause further fission – so that once the process has started it can continue indefinitely.
The energy of fission can be released slowly, bit by bit, and used to heat water. The steam from the water is then used to drive a generator, which produces electricity. This is the principle of nuclear reactor.
Because of the technical difficulties and safety concerns the use of nuclear power is limited. When nuclear power is released from an atom, deadly rays can escape. This nuclear radiation is very harmful. Hence the nuclear reactor at a power plant is surrounded by thick concrete walls for safety.