Electricity was generated by a nuclear reactor for the first time ever on September 3, 1948, at the X-10 Graphite Reactor in Oak Ridge, Tennessee, which was the first nuclear power station to power a light bulb. The second, larger experiment occurred on December 20, 1951, at the EBR-I experimental station near Arco, Idaho.
On June 27, 1954, the world's first nuclear power station to generate electricity for a power grid, the Obninsk Nuclear Power Plant, started operations in Obninsk of the Soviet Union. The world's first full scale power station, Calder Hall in England, opened on October 17, 1956. The world's first full scale power station solely devoted to electricity production—Calder Hall was also meant to produce plutonium—the Shippingport Atomic Power Station—was connected to the grid on December 18, 1957.