The first electrical power was produced on December 18, 1957 as engineers synchronized the plant with the distribution grid of Duquesne Light Company.

[6] The third and final core used at Shippingport was an experimental, light water moderated, thermal breeder reactor.

[8] Over its 25-year life, the Shippingport power plant operated for about 80,324 hours, producing about 7.4 billion kilowatt-hours of electricity.

A proposal by Duquesne Light Company was accepted by Admiral Rickover and the plans for the Shippingport Atomic Power Station started.

The only suitable reactor available at the time was the one that was intended for the nuclear-powered aircraft carrier desired by the Navy, but which Eisenhower had just vetoed.

The ground-breaking ceremony was initiated by Eisenhower from Denver where he was giving a talk on atomic energy on Labor Day; Rickover ensured that the unmanned bulldozer pushing dirt did not dig in and stall by having the dozer blade riding along two railroad rails buried under six inches of dirt.

[6] Shippingport was created and operated under the auspices of Admiral Hyman G. Rickover, whose authority included a substantial role within the United States Atomic Energy Commission (AEC).

[citation needed] The third and final core was a light water breeder, which began operating in August 1977 and after testing was brought to full power by the end of that year.

After five years (29,000 effective full power hours)[14] the core was removed and found to contain nearly 1.4% more fissile material than when it was installed, demonstrating that breeding had occurred.

[17] In December 1988, the 956-ton (870-T) reactor pressure vessel/neutron shield tank assembly was lifted out of the containment building and loaded onto land transportation equipment in preparation for removal from the site and shipment to a burial facility in Washington State.

While the Shippingport Reactor has been decommissioned, Beaver Valley Nuclear Generating Station Units 1 and 2 are still licensed and in operation at the site.

[citation needed] The $98 million (1985 estimate) cleanup of Shippingport has been used as an example of a successful reactor decommissioning by proponents of nuclear power[who?