Docket Number
80 MW
San Bernardino County
Solar Thermal
Project Status
Operational (Solar Thermal)
Project Type
Application for Certification
Project Description

The Solar Energy Generating System (SEGS) IX and X project is located at 43880 Harper Lake Road, 7 miles northeast of Highway 58 on a 500-acre site. Additional SEGS projects were planned in the immediate vicinity, but were cancelled for various reasons, including the lack of transmission capacity from the area.

SEGS IX is an 80-megawatt (MW) field of parabolic mirrors supplemented by natural gas to produce electricity. Heat from the mirrors is concentrated on tubes of heat transfer fluid (HTF) which is circulated to steam boilers to produce electricity. During the peak season, the project generates 80 MW of electricity to the Southern California Edison transmission grid. Mirror washing takes place Monday through Friday from 8:00 pm to 5:30 am.

In 1991, the project owner was unable to finance SEGS X because of financial and regulatory constraints; therefore, SEGS X was never built.

On July 8, 2020, the CEC approved a PCA (TN 233900) approving the construction of a battery energy storage system (BESS), with a maximum capacity of up to 80 MW, between the SEGS VIII and IX facilities.

On September 11, 2020, a Post-Certification Amendment was docketed (TN 234663) proposing to remove SEGS X from the final CEC Decision, effectively ending the CEC’s jurisdiction over this portion of the SEGS IX and X site. Construction for SEGS X was initiated but the facility was never built and did not become operational. The project owner has indicated they may redevelop the SEGS X portion of the site for a solar photovoltaic (PV) and battery energy storage project. Permitting for such redevelopment would be under the jurisdiction of the County of San Bernardino.

Power Plant Certification and Exemption Processes

As required by the Warren-Alquist Act, the Energy Commission monitors Commission-certified energy projects throughout construction, operation, and closure to ensure compliance with the conditions of certification imposed by the Commission’s Final Decision for approving the projects.

Original Proceeding

e-Commenting has been closed. Please submit your comments in compliance proceeding above.

Docket Log (89-AFC-01)

Exhibit List

Proof of Service List

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Project Manager

John Heiser

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