Base Power brings cheap batteries to residents in power-starved PJM

PJM Interconnection, which serves 67 million people across 13 states from the mid-Atlantic to the Midwest, has become a poster child for how not to keep up with soaring energy demand. Startup Base Power is taking a whack at that problem by installing a network of unusually large home batteries in one corner of that regional grid.

Starting today, the first 2,000 customers in Illinois utility ComEd’s territory who sign up with Base Power can get a 40-kilowatt-hour home backup battery for just $95 up front. Subsequent customers will pay $295, still a mere sliver of the $10,000 or more that a backup-capable home battery normally costs. All these customers will then buy retail electricity from Base Power at a 25% discount to the prevailing ComEd rate, which was 10.4 cents per kilowatt-hour this summer. Customers sign a 12-year battery agreement, but can pay a $500 deinstallation fee if they want out early.

This business model gives customers in Chicagoland more options for cheap and resilient power while also giving Base Power the rights to operate the battery fleet in response to broader market dynamics. Base Power will be adding capacity in the northwesternmost territory of the constrained regional grid, but its unique model allows it to avoid PJM’s ossified procedures for expanding large-scale grid production.

“We are deploying capacity behind the meter at the residential home, where an interconnection already exists, so we don’t wait in the interconnection queue,” said Base Power’s founder and CEO Zach Dell. ​“There’s some work around that, but it’s certainly less onerous and much faster than the large-load interconnection queue.”

PJM famously hosts the densest corridor of data centers, in northern Virginia, but the AI buildout has taken off in Indiana, Ohio, and Pennsylvania as well. While hyperscalers stare down yearslong waitlists for new gas turbines to meet their colossal power needs, Base Power can install miniature power plants every day, which add up over time.

The Illinois offering is even cheaper than Base Power’s prices in its home state of Texas, where it has installed more than 500 megawatt-hours of storage since it launched in 2024. Base Power operates most of that in the Texas’ freewheeling, competitive energy market, but it also is working with a cooperative utility to install 100 megawatts of instant discharge capacity at customer homes over the next two years.

Base Power’s two-part pitch of customer benefit and aggregated grid resource has made it arguably the most effective fundraiser in the residential battery space — it netted a billion-dollar raise last fall from mainstream VCs like Andreessen Horowitz and Valor Equity Partners, an early backer of Tesla and SpaceX. Base Power needs that cash to fuel its vertically integrated model: It designs, manufactures, markets, installs, owns, and operates all the batteries in-house.

After a few years of tremendous growth, though, the question had remained whether this model would work outside the particularities of the Texas market. Now, Base Power is staking a claim on a new state that provides access to the country’s biggest regional power market.

Several layers of policy and regulation made Illinois the right entry point for Base Power in PJM. The state allows retail competition, so Base Power can sell power directly to customers. However, it still has to get permission from a wires utility to hook up the batteries to the distribution grid, and ComEd stood out as a partner.

“ComEd, they’re an innovative utility,” said Travis Kavulla, Base Power’s head of policy, who on Monday was tapped to run the Bonneville Power Authority, a New Deal–era federal power agency. ​“They’ve done things that other utilities have not done.”

In particular, ComEd has rules that compensate homes at market rates for discharging power to offset high capacity prices in PJM. These rules emerged from a recent revision to the long-standing net-metering policy, which originally paid homes for shipping excess rooftop solar to the grid; now, the policy also allows stand-alone batteries to export power and participate in the market.

Base Power will also tap into a new Illinois policy to encourage virtual power plants that was created by the Clean and Reliable Grid Affordability Act, which became law in January. Starting this summer, battery customers can receive a rebate if they install a battery and agree to discharge it to the grid for multiple hours during the evening peak on a certain number of summer nights. It’s a simple way to ensure that the batteries make themselves useful, and Base Power will apply that rebate to support its very low pricing.

All this means that Base Power will not rely on specific PJM programs to make money in Illinois. The grid operator is working on a new mechanism for distributed energy resources to play a broader role in capacity markets, in response to the Federal Energy Regulatory Commission’s Order 2222. That process will have its first auction next month, to pay for capacity in 2028 and 2029, Kavulla noted.

“Our approach is not something that has to wait on that. It’s more ready to go to market if you’re configuring it on the retail side through a competitive retailer, in the way we’re doing it,” he said.

Down the road, the startup could tap another source of revenue by selling aggregated capacity to hyperscalers that need power for new data centers. Google signed a bilateral deal with demand-response provider Voltus to do just that in PJM. Sunrun, Tesla, and Renew Home just announced a national strategy to tap existing home batteries and smart thermostats to sell capacity to data center customers. Dell confirmed that Base Power is in talks with data center clients, but said his Illinois strategy does not depend on that kind of deal.

Whether or not Base Power deals directly with data centers, the households in Illinois are feeling upward pressure on their energy bills as the region struggles to supply the AI arms race. Some governors have threatened to exit PJM if the capacity costs keep rising, though that would take years of thorny wrangling to execute. If other PJM states want to do something to help customers short of the nuclear option, they could look to the ComEd policy that rewards households for peak exports.

“One of our takeaways here is that if you’re a state in PJM, this is something that you can kind of cause your utilities to do,” Kavulla said.