It was in 1934 that the Hungarian-born American Leo Szilard (see photo) came up with the basic idea for nuclear power. The brain-wave came while he was waiting for the traffic lights to change in London. He visualized one atom of uranium disintegrating, and giving off a neutron or two that went on to split yet more uranium atoms. Leo Szilard thought that this would bring about a 'chain reaction' leading to an enormous release of energy. In 1942, he set up, with Enrico Fermi, the first atomic 'pile' at Chicago University. Later, he became part of the Manhattan Project which aimed at making the first atom bomb. He feared that nuclear attack of Japan would produce terrible tragedies. But his pleas for a demonstration test of an atom bomb to scare the Japanese into surrender fell on deaf ears.
By latest count (Jan 2010), there are 440 nuclear power stations in the world, producing 3,73,000 megawatts of electricity. These numbers may increase rapidly in the time to come.
Leó Szilárd (Wikipedia)
Nuclear power (Wikipedia)