Columbia Generating Station

The Columbia Generating Station, is a nuclear power station located on the United States Department of Energy Hanford Site, 12 miles (19 km) NW of Richland, Washington. Its site covers 1,089 acres (441 ha) of Benton County, Washington.

This plant is owned and operated by Energy Northwest, a consortium of Pacific Northwest public utilities. Energy Northwest's original name was the Washington Public Power Supply System (WPPSS). Construction began in late 1975, and the NRC issued an operational license for the plant to begin producing power in March, 1984.

In 2000, WPPSS changed its name to Energy Northwest, and later the plant's name was changed from WNP-2 (Washington Nuclear Power unit number 2) to Columbia Generating Station. Of the five commercial reactors originally planned by WPPSS for the State of Washington, this reactor was the only one completed (WNP-1 may yet be completed but WNP-4, WNP-3 and WNP-5 were abandoned).

The reactor provides Washington with approximately 4% of the state's electrical generation capacity. With the 1992 retirement of Oregon's Trojan Nuclear Power Plant, it is the only commercial nuclear power reactor remaining in the Pacific Northwest. The nearest operating reactor is the Diablo Canyon Power Plant located on the Southern California beach in San Luis Obispo County, California. The plant's sole reactor is a General Electric Type 5, a newer version of the type of reactor used at the Fukushima Daiichi Nuclear Power Plant. The plant had a new Westinghouse Electric turbine-generator installed in 1999, which brought its output rating to 1,150 MWe.

The Columbia Generating Station features six low-profile fan-driven cooling towers. Each tower cascades warmed water, a byproduct of water heat exchanging with steam after leaving a turbine, down itself and subsequently cools the warmed water via a combination of evaporation and heat exchange with the surrounding air. Some water droplets fall back to earth in the process, thereby creating a hoar frost in the winter. At times, the vapor cloud from the cooling towers can reach 10,000 feet (3 km) in height and can be seen at a great distance. Replacement water for the evaporated water is drawn from the nearby Columbia River.

Columbia's original license to operate would have expired in 2023. In January 2010, Energy Northwest filed an application with the Nuclear Regulatory Commission (NRC) for an extension until 2043. In May 2012, the NRC approved the 20-year extension.