Utilities are increasingly using large battery systems to store electricity, helping meet peak demand, support renewable energy and hold down prices.

Those benefits have prompted states across the country to offer incentives for more battery storage. But the expansion has also run into resistance. A new wave of battery facilities are being built in or near densely populated areas, where some residents and local officials worry about the risk of fires.

Battery energy storage systems charge when electricity is plentiful and demand is relatively low. They then send that stored power back to the grid when demand rises.

Battery storage also allows utilities to rely more on renewable energy sources by making them more efficient: It retains excess energy from wind and solar power that can be used when those sources aren't producing. And using stored energy from both renewable and nonrenewable sources to meet high demand saves the expense and environmental impact of burning fossil fuels to ratchet up production.

There's now a push to place smaller battery systems, typically up to 5 megawatts, in urban and suburban areas. That's enough to power thousands of homes, but they usually need less than a quarter of an acre of space, with the batteries enclosed in steel-walled containers.

Putting smaller arrays closer to where people live has several advantages. Smaller projects can get up and running faster than bigger sites, developers say. Batteries near population centers relieve congestion on the grid during high demand by distributing power directly to the surrounding area. And in communities with private rooftop solar panels, the batteries can absorb excess electricity from those sources, with less of it being lost than if it had to travel to more-remote storage.

"You can fit them in the edges of unused land," says Pier LaFarge, chief executive of utility-services company Sparkfund, which is helping deploy batteries in suburban and urban areas for utility Xcel Energy in Minnesota. "It adds up to a really big impact on the grid and communities."

Worries about fires

The batteries are appearing across the country. There were nearly 370 battery sites of 5 megawatts or less in the U.S. as of July, more than triple the number in 2020, according to data provided to The Wall Street Journal by the U.S. Energy Information Administration. Their combined capacity was more than 840 megawatts, enough electricity to power hundreds of thousands of homes. The data excluded projects that are for commercial or industrial uses. Not all battery sites under 5 megawatts are in urban or suburban areas, but developers say the smaller sties are more likely than larger ones to be closer to population centers.

There might be more sites if it weren't for the concerns they often provoke. Local governments had at least 111 active moratoriums or bans on battery-storage sites as of August, up from 76 in January, according to battery-storage development company Carina Energy. Moratoriums, which are far more widespread than outright bans, typically pause development for more than a year.

The main source of concern is fear of toxic fires. New York state, where there have been five fires at battery sites since 2023, accounts for 74% of current moratoriums, followed by Washington state with 6% and California with 4%, according to Carina Energy.

As an example of what people fear, hundreds of residents in Monterey County, Calif., were evacuated early last year after a fire broke out at the Moss Landing Power Plant, a battery storage site. A second fire broke out at the site in September, during continuing cleanup and demolition, after hundreds of still-energized batteries spontaneously ignited.

Storage-site developers say the technology is safer today, and safety standards are stricter, than when many older sites were built. Dustin Mulvaney, a San Jose State University environmental-studies professor, agrees, saying that projects permitted after 2022 follow tougher industrywide standards enforced by governments, such as codes that require battery containers to be more rigid and able to contain fires, to prevent the spread of flames within a site. Newer standards also require testing of containers to see how they react to fire.

But those assurances haven't quelled the opposition.

"It is an issue residents are so passionate about that they are attending their first-ever town board meetings and sending emails of opposition to supervisors and board members," says Violet Martin, who in January started a Facebook group called No Battery Storage in the ADK, which is focused on New York's Adirondack region. The group has more than 4,000 members and has helped coordinate outreach to more than 90 towns.

"They cannot guarantee there will not be a fire," says William Scarborough, a former New York state Assembly member and current president of the Addisleigh Park Civic Organization in the New York City borough of Queens.

NineDot Energy-a developer, backed by Carlyle Group and Manulife Financial's investment arm, building dozens of battery locations in New York City-is converting a former gas station to a battery-storage site in the St. Albans neighborhood of Queens. The batteries would be more than 20 feet from the nearest home, the company says. Protesters have opposed the project, and others by NineDot, for more than a year, Scarborough says.

NineDot already has five locations operating in the city. Its projects lower costs for residents and help prevent power outages, says Adam Cohen, the company's co-founder and chief technology officer. "These projects seem novel when they come to a community," he says. "My hope and expectation is that these just become boring, everyday things." The company says battery storage in New York follows the nation's leading fire-safety rules to provide maximum protection to the surrounding communities.

Safety improvements

Scarborough says he supports stricter statewide legislation, which failed to pass last year, that would require a 300-foot buffer zone between sites and homes, among other rules.

Legislation requiring a 300-foot buffer zone would have severely limited the expansion of battery storage in the state, says state Sen. Kevin Parker, who represents Brooklyn and chairs the Energy and Telecommunications Committee. "Battery storage looks like the next major opportunity to make sure our grid is stable and we're providing sustainable energy," he says.

Even if opposition slows projects, developers say they expect more batteries to come closer to neighborhoods in the years ahead. NineDot Energy's Cohen says outside regulators and utilities are looking to New York City as an example. "If you can build it here, you can build it anywhere," he says.

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