- Docket Number
- 660 MW
- Colusa County
- Combined Cycle
- Project Status
- Operational (Natural Gas-Fired)
- Project Type
- Application for Certification
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.
- Order Approving Modification of Air Quality Conditions of Certification, TN 52443, 07/16/2009, Order No. 09-0715-02, Commission approval to modify the general equipment arrangement, eliminate diesel emergency generator, replace diesel fire pump with electric fire pump, eliminate aux boiler, relocate natural gas metering station, incorporate natural gas water bath heater system and add a wet surface air cooler.
- Notice of Determination for Approval to Install a New Type of Clarifier, TN 201431, 12/13/2013, Staff approval to remove existing Lamella clarifier, which is part of the water filtration process.
- Notice of Determination for Approval of On-Site Storage of a Spare Generator Step-Up Transformer, TN 201878, 03/14/2014, Staff approval to store a spare three-phase, 265 MVA Generator Step-Up transformer on site for future use as replacement equipment.
- Order Approving a Petition to Amend to Allow Project Water to be Temporarily Trucked to The Site, Not in Docket, Order No. 14-0422-05, Commission approval of temporary truck water delivery to the project site until a new alternate water supply pipeline can be constructed.
- Notice of Determination for Approval to Construct a Permanent Back-Up Water Supply Pipeline, TN 202974, 08/22/2014, Staff approval Construct new permanent underground pipeline along access road to directly draw water from Glen Colusa Irrigation District’s Glen Colusa Canal.
- Approval of Requested Modifications to Install a Fin Fan Cooler and Expand Turbine Deck Grating, TN 204312, 04/22/2015, Staff approval of two separate petitions to install a fin fan cooler to cool HRSG effluent; and to expand the deck grating area around the steam turbine.
- Order Approving a Petition to Amend to Revise Air Quality Conditions of Certification, TN 207036, 12/15/2015, Order No. 15-1209-03, Commission approval to modify Air Quality Conditions of Certification for Consistency with Federal Title V Operating Permit issued by the Colusa County Air Pollution Control District (District) on September 1, 2014.
- Notice of Determination for Approval to Add a New Warehouse and Electrical Equipment for ACC Soft Start, TN 214076, 10/17/2016, Staff approval to add a new warehouse and to add electrical equipment to allow gradual load increase to electrical motors of the air-cooled condenser.
- Notice of Determination for Approval to Install Rotating Intake Screens to Control Algae Blooms, TN 217513, 05/09/2017, Staff approval of installation of rotating intake screens to control algae blooms at the water intakes for the Tehama Colusa Canal, and associated equipment at the TCC pump.
- Notice of Determination for Approval to Add a Permanent Stairway, TN 217920, 06/07/2017, Staff approval for addition of permanent stairway to access two condensate return pumps for the air-cooled condenser.
Attention: Non-hypertext items above will need to be requested from the Compliance Project Manager, along with the document TN number, if provided above.
Power Plant Certification and Exemption Processes
The CEC has the exclusive authority to certify all thermal power plants 50 megawatts (MW) and larger and related facilities proposed for construction in California. The Application for Certification (AFC) process is a certified regulatory program under the California Environmental Quality Act (CEQA). As a certified regulatory program, the CEC does not prepare environmental impact reports (EIRs) in an AFC proceeding, but instead prepares environmental assessment documents that are functionally equivalent to EIRs. A certificate issued by the CEC is in lieu of any permit, certificate, or similar document otherwise required by any state, local or regional agency, or federal agency to the extent permitted by federal law, and supersedes any applicable statute, ordinance, or regulation of any state, local, or regional agency, or federal agency to the extent permitted by federal law.
e-Commenting has been closed. Please submit your comments in compliance proceeding above.
Public Participation Questions
Media & Public Communications Office