Plans for 1.2 GWh California battery project approved

Councillors in Poway City, California, have greenlit an application for a 300 MW/ 1.2 GWh lithium iron phosphate (LFP) battery site, despite fire and safety fears expressed by residents.

The four-hour storage system will be developed by Arevon Energy and be constructed on a 10-acre site. It will feature 329 battery enclosures hosting Tesla MegaPack batteries, according to council planning documents.

Nearby residents voiced concern about fire and safety at a pre-development conference in which details of the original application were outlined in February 2022.

As a result, Arevon opted for lithium iron phosphate battery technology to ensure safety. The developer also moved to an underground transmission line to the San Diego Gas & Electric substation at Miramar Air Base, to address criticism of overhead lines mentioned in the original application.

The community benefits pledged by Arevon as part of the planning application include an agreement to reimburse Poway City for any expense associated with fires at the site.

The battery project, on Kirkham Way, secured approval from councillors on August 20, and also features permission for an electricity substation.

Newspaper The San Diego Union-Tribune has reported plans for the underground transmission line will have to be rubber-stamped by the city authorities, on August 29, after which construction is expected to start in September and to take 10 months to 12 months to complete.

The planning documents also indicated the site will contain space for up to 987 “capacity maintenance augmentation units,” to maintain battery performance as the devices degrade over time.

Planning consent was awarded for a 30-year project lifetime. After that, the documents stated, “most of the equipment will be recycled.”

Battery fires are a sensitive topic in California following recent fire incidents, including a blaze at a 250 MW site in the Otay Mesa county of San Diego, which broke out on May 15, 2024 and took almost 17 days for firefighters to extinguish.