Vacaville council holds study session on utility-scale battery storage as large, often emotional public turnout urges ban on lithium-ion systems

Vacaville ' The Vacaville City Council on Dec. 9 heard more than two hours of public comment and a staff presentation during a study session on utility-scale battery energy storage systems (BESS), a technology state law encourages and that several energy companies have proposed to site near the city.

Senior planner Albert Enoltz told the council staff's draft ordinance would allow large, front-of-meter BESS only in limited zones (public facility, industrial park and business park), exclude high or very-high wildfire hazard areas and Nut Tree Airport compatibility zones, and require a rigorous permitting process that includes a preliminary community meeting, technical analysis and a public benefit plan. Enoltz said the draft uses a 300-foot buffer from sensitive receptors (residences, hospitals, nursing homes) and is modeled in part on Solano County's ordinance; the city currently has a moratorium on new BESS projects that expires May 14, 2026.

The session drew more than two dozen speakers, many representing an organized group calling itself "Keep Back Vaca Safe," and included Solano County Supervisor Mitch Mashburn. Speakers urged the council to prohibit lithium-ion BESS inside city limits, citing incidents elsewhere that released toxic smoke and heavy metals, forced large evacuations and shut corridors. "A BESS fire could spread toxic, breathable dust throughout our community," said organizer Sarah Dunn, representing the neighborhood coalition. Supervisor Mashburn urged the council to prioritize rural industrial sites the county has identified, rather than city-adjacent locations near schools, water facilities or neighborhoods.

Council members pressed staff on legal limits given state statutes (AB 205 and SB 254) that allow certain projects to opt into California Energy Commission (CEC) review. Staff and the assistant city attorney said a well-documented local ordinance gives the CEC a framework to consider and can strengthen the city's position in that process; the city manager said staff will work with lobbyists and partners to pursue legislative changes if council wishes. Mayor John Carley framed the meeting as a study session to collect public comment and refine options before returning for further hearings.

Several councilmembers explicitly said they were unwilling to approve siting that uses lithium-ion chemistries prone to thermal runaway. "I am not going to support any lithium-ion or any battery technology that poses a thermal-runaway risk anywhere near our community," Councilmember Stockton said. Staff said it will continue technical work (including battery-type assessments with outside consultants), refine setbacks and suitability screening, coordinate with the county and return with a revised ordinance and options for council direction.

Because the CEC can consider local rules but also can make overriding determinations in some opt-in cases, councilmembers discussed parallel strategies: adopt a stringent local ordinance, seek regional alignment with Solano County, and pursue state-level legislative or administrative changes to tighten the opt-in process. The study session generated substantive technical questions about plume modeling, water contamination, emergency-response capacity and utility interconnection needs; staff noted some of those answers will require further engagement with PG&E, Caltrans and other agencies.

The council did not take a final vote on the draft ordinance; staff will revise the draft, complete additional analyses requested by council, and return for planning commission and subsequent council hearings ahead of the city's moratorium expiration.

Next steps: staff will refine the draft based on council feedback, pursue technical analyses (plume, water, noise, rail and utility coordination), continue public outreach, and consider legislative outreach to state representatives to address perceived gaps in the opt-in process.