Waymo Robotaxis Give Used Batteries Second Life on Power Grid

The robotaxis driving themselves around San Francisco and Austin are about to do double duty for the planet.

Waymo announced a partnership with B2U Storage Solutions on June 4 that will send thousands of used batteries from its autonomous taxi fleet to power grid storage facilities. Once these batteries retire from shuttling passengers, they'll spend several more years capturing solar and wind energy and releasing it when communities need it most.

The timing couldn't be better. Waymo's robotaxis rack up far more miles than typical electric vehicles because they're working around the clock. That means batteries degrade faster and need replacing sooner, but they still have plenty of life left for less demanding work.

"There's still a lot of life left in the battery," Adam Lenz, Waymo's head of sustainability, told Ars Technica. The company swaps batteries proactively to keep its fleet running efficiently, not because the batteries are useless.

The numbers add up to serious impact. Waymo's nearly 4,000 vehicles mostly use Jaguar I-Pace models with 90 kilowatt-hour batteries. Even after losing some capacity from years of taxi duty, each battery can still store enough energy to power several homes.

Freeman Hall, CEO of B2U Storage Solutions, says the partnership could eventually deliver "hundreds of megawatt-hours" of storage capacity to support local grids. His company has already repurposed over 1,300 electric vehicle batteries at its Lancaster, California facility.

The Ripple Effect

What makes this partnership especially clever is the circle it creates. Waymo robotaxis charge on local power grids, many powered by renewable energy. When their batteries retire, they flow right back into those same communities to help stabilize the grid.

Used Waymo batteries will support energy storage projects across California and Texas, including a 24 megawatt-hour facility in Bexar County, Texas that serves San Antonio where Waymo operates. The batteries capture excess solar and wind power during low-demand periods, then release it during evening peak hours when families come home and crank up their air conditioning.

B2U has already started receiving the first batches of batteries from Waymo's fleet. The agreement gives Waymo flexibility on timing and quantities, but both companies expect the flow to grow as the robotaxi fleet expands.

The arrangement extends battery usefulness by years while supporting the clean energy grid that charges the next generation of Waymo vehicles. It's the kind of circular solution that makes both environmental and economic sense.

This partnership rides a bigger wave of progress too. The United States installed 9.7 gigawatt-hours of battery storage in the first quarter of 2025 alone, the largest first quarter in history and a 32 percent jump from the previous year.

Every retired robotaxi battery is getting a chance to keep serving communities long after its road trips end.