Colusa Generating Station

The Colusa Generating Station (CGS) is located in the unincorporated portion of Colusa County, approximately 6 miles north of the community of Maxwell, on a 100-acre parcel that is leased from the 4,800-acre Holthouse Ranch property, approximately 14 miles north of Williams and 4 miles west of Interstate 5.

CGS is a nominal 660-megawatt natural gas-fired, dry-cooled, combined-cycle electric generating facility, consisting of two General Electric (GE) Power Systems Frame 7FA combustion turbine generators equipped with dry, low-NOx combustors designed for natural gas. Included are two multi-pressure heat recovery steam generators (HRSG) with duct burners and a selective catalytic reduction system (to be used with aqueous ammonia) and equipped with an oxidation catalyst to control volatile organic compounds and carbon monoxide emissions, one steam turbine generator system with multi-cell, air-cooled condenser and associated auxiliary system and equipment, and a 1,000-kilowatt standby diesel generator for extended utility outages during maintenance and shutdowns.

Water for the project is provided by the Glenn-Colusa Irrigation District (GCID) via the Tehama-Colusa Canal (TCC), which is located to the west of the project site. CGS uses a Zero Liquid Discharge wastewater system which recovered the water from the combustion turbine generator’s evaporative coolers for reuse in the plant, and the remaining salts are concentrated for disposal off site. Air emissions from the facility are controlled using Best Available Control Technology with air pollution credits obtained from the Colusa County Air Pollution Control District.

The facility is interconnected to the nearby existing electrical infrastructure owned by Pacific Gas and Electric (PG&E). The electrical switchyard and transmission facilities allow delivery of the power plant’s output to PG&E’s existing Cottonwood to Vaca-Dixon 230-kilovolt (kV) transmission corridor located approximately 1,800 feet east of the project site.

On April 2014, the California Energy Commission approved a Post-Certification Amendment (TN 202974) to construct an approximately 0.86-mile back-up water supply pipeline from Glen Colusa Canal, owned by the GCID, to the CGS. The back-up water supply pipeline transports GCID water allocated to the CGS when there is insufficient water in the TCC for use by CGS. The back-up water supply pipeline eliminates the need for trucking the water to the site, as approved under an emergency amendment petition approved in April 2014.