Potentia-Viridi 400 MW/3200 MWh BESS

The Potentia-Viridi Battery Energy Storage System (BESS) project in Alameda County, California, was approved by the California Energy Commission (CEC) on May 26, 2026, as the third project to successfully navigate the State’s AB 205 Opt-In Certification Program. Developed and owned by Clearway Energy Group, the project is currently planned as a 400 MW battery energy storage facility with up to 3,200 MWh of storage capacity.

Coffman supported the project with multidiscipline design engineering and permitting services from early conceptual design to regulatory approval.

In collaboration with specialty consultants, Coffman developed preliminary designs, environmental evaluations, and application documentation. Scope of services included development and optimization of multiple configurations including combinations of 2-, 4-, and 8-hour Energy Storage Solution (ESS) yards, a high-voltage collector substation, and gen-tie line for interconnection to the nearby Tesla PG&E substation. Specific efforts included civil, electrical, and fire protection engineering related to proposed infrastructure. Fire Protection support included negotiation and interface support with the local Fire Marshal, and development of key documentation such as the Fire Protection Basis of Design (BOD), Fire Master Plan (FMP), and Emergency Operations Plan (EOP).

Rendering provided by Clearway Energy Group