Battery energy storage systems, or BESS, will not be permitted by Solano County for now. On Tuesday, the Board of Supervisors voted unanimously to extend an emergency moratorium on permits through Jan. 23, 2026.

The energy storage units are a key component of Gov. Gavin Newsom’s push for California to obtain 100 percent of its electricity from carbon-free sources by 2045. In theory, municipalities can use the energy they store to power their grids with less of a carbon footprint. But questions about their long-term effects persist.

Permits for BESS were temporarily prohibited by Solano County in January, in response to public concerns over their safety.  The 45-day moratorium was requested by Allan Calder and James Bezek, planners in Solano County’s Department of Resource Management.  

Their request was triggered by a permit application from Corby Energy, a subsidiary of NextEra Energy Resources, for a new BESS near the PG&E Vacaville-Dixon substation. If constructed, it would be one of the largest BESS facilities in the state, and it would be situated on prime-agricultural land.

A Battery Energy Storage System, or BESS, is shown in a framegrab from an undated product video. A state law allows BESS developers to obtain permits directly from the California Energy Commission, bypassing local approval processes. But that is raising concerns in places like Solano County that the giant lithium-ion battery farms could put communities at risk from fires, hazardous materials, and loss of agricultural land. (TE Connectivity/YouTube)

BESS facilities are rows of containers that house hundreds of lithium-ion batteries. They store energy from wind and solar farms that can be used after the sun sets and the wind dies down. Fires caused by the systems are rare, but they can release chemicals and gasses that are new for local governments to manage.

The planners say they need the time to write local building codes and regulations that will reduce potential harms the facilities might create over time, but even then, local governments do not have full permitting power over BESS facilities.

In 2022, California passed a bill giving energy companies the ability to get opt-in certification directly from the California Energy Commission, overriding local permits or requirements by other agencies.

Calder said the county’s ordinance would not, and could not, preclude a potential developer from opting into the state process.

As of Tuesday, a spokesperson for the California Energy Commission said they have not been contacted by Corby Energy to request an opt-in certification.