OMEC is a combined-cycle power plant, fueled by natural gas and fitted with air emissions control technology. In addition, Calpine paid to retrofit older marine vessels and sanitation vehicles with emission control technology in order to generate mobile emissions credits that have reduced overall pollution in the region.

The company said that these permanently retired emissions more than offset emissions from the plant, resulting in a net air quality benefit for the San Diego region. The facility will conserve water by eliminating the need to use ground or potable municipal water to cool recirculated steam.

The plant, with a capacity of almost 600MW, began commercial operation on October 3 and is generating electric power for customers of San Diego Gas & Electric in the region.

Michael Peevey, president of the California Public Utilities Commission, said: “By bringing this facility online we can further our goal of retiring older, aging power plants in the region.”

The Otay Mesa Energy Center is expected to increase Calpine’s California portfolio to 38 power plants and more than 5,800MW including 725MW of renewable geothermal energy. Calpine’s geothermal facilities at The Geysers supply about 20% of California’s renewable electric generation.

Jack Fusco, president and chief executive officer of Calpine, said: “We are excited about this and our future projects in this great state and look forward to breaking ground on two other facilities, the Russell City Energy Center in Hayward and the expansion of Los Esteros Energy Center in Northern California.”