a16z-backed Base Power offers cheaper electricity to power grids, addressing interconnection queue delays and reducing data center electricity costs.

Energy storage startup Base Power began selling its massive home battery systems to residents of Illinois yesterday, Canary Media reported. Crucially, this marks the startup's first foray into the grid territory operated by PJM Interconnection, the largest U.S. grid operator by territory, and one that has particularly struggled to cope with an onslaught of new data centers.

Beyond Illinois, PJM's territory includes Northern Virginia, one of the densest data center regions on the planet. That density, coupled with a paucity of new generating sources, has caused wholesale electricity prices in PJM to nearly double over the past year. The power crunch has gotten so bad that AEP, one of the region's largest utilities, has threatened to leave the market.

Base Power launched two years ago in Texas to build a virtual power plant centered around residential batteries. Base's batteries start at 25 kilowatt-hours and are larger than those of many competitors. Rather than sell the batteries, the company requires customers to purchase electricity from it. In Illinois, its rates are 25 percent below ComEd's.

The startup's timing has also been impeccable. Base is currently operating more than 500 megawatt-hours of battery storage in Texas, charging when electricity prices are cheap and dispatching them when the grid needs it most.

Base's entry into the PJM grid comes at a time when the operator has come under scrutiny for bungling its handling of rising electricity demand. PJM had paused applications for new generating sources starting in 2022, only reopening the queue in April. The timing for PJM could not have been worse—electricity demand has skyrocketed in the last four years.

Base's rollout has gathered pace since October, when it announced a $1 billion round led by Addition. That round followed closely on the heels of a $200 million round led by Andreessen Horowitz, Lightspeed Venture Partners, and Valor Equity Partners in April 2025.

Historically, PJM has been slow to adopt new technologies like distributed energy storage, but Base's residential focus helps it do an end-run around the sclerotic grid operator.

"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," Zach Dell, Base Power's founder and CEO, told Canary Media.