Base Power has just unveiled Core, a supersized 39.2-kWh home battery that it says can keep a house running for up to 36 hours and be installed in under an hour.
The Austin energy company designed Core to do two jobs: provide automatic whole-home backup during an outage and operate as part of Base’s growing virtual power plant when the grid is running.
Base says Core stores about three times the capacity of a typical home battery. Homes can get two units for 78.4 kWh of storage and up to 72 hours of backup with reduced electricity use. Actual runtime will depend on what’s running – air conditioning, for example, will drain it faster.
Core can be connected to solar, and it also has a built-in port for recharging from a portable generator. The Base app provides real-time estimates of how much backup time remains based on both current and reduced power use.
When the grid goes down, Core switches the home to battery power in 50 milliseconds. The lithium iron phosphate (LFP) battery is designed to operate between -22F and 122F, carries an IP67 rating for submersion in up to 3 feet of water, and has also undergone high-pressure water and flash-flood testing.
“We brought together the best hardware and software engineers in the world to build Core – a battery designed to protect American homes while supporting the grid,” said Zach Dell, CEO and cofounder of Base Power. “It installs in under an hour, switches over seamlessly, is built to handle extreme weather, and delivers extended outage protection at a price Americans can afford.”
Base designs, builds, installs, and maintains Core, and it retains ownership of the battery. That’s important because homeowners aren’t buying a 39.2 kWh system outright. Instead, they sign up for a Base plan, and the company uses the networked batteries to supply power to the grid when demand and wholesale prices spike.
That grid revenue helps subsidize the customer’s backup system. As one current Texas example, Base advertises a $695 installation fee and a $19 monthly membership fee in Oncor territory, along with a fixed electricity plan.
Core is now rolling off the line at Base Factory 1 in Austin. The company says the factory is producing thousands of systems a month, with Base’s in-house deployment crews installing them at homes.
That’s quite a leap from where Base was in October 2025, When Electrek reported on its previous $1 billion raise. At that point, the company had deployed more than 100 MWh of residential battery capacity and was preparing to open its first factory. Its battery fleet has since grown to more than 500 MWh, and Base has expanded from Texas into Illinois.
Base has also launched utility programs with El Paso Electric, Austin Energy, and CoServ totaling more than 200 MW of capacity.
Now, Base has raised another $1 billion, this time in a Series D that values the company at $13 billion post-investment. Ribbit, Addition, Valor Equity Partners, and JPMorganChase’s Strategic Investment Group led the round, with participation from new and existing investors.
The financing brings Base’s total capital raised to more than $2.5 billion. The company says it will use the money to put Core in more homes, expand across the US, and hire more employees.
Base Core is available now to homeowners in select parts of Texas and Illinois.
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