GM's Electric Vehicles Can Now Power Homes and the Grid

Some 250,000 electric vehicles manufactured by General Motors are driving around the US today with an oft-secret capability: Their big, powerful batteries can charge other things. Potentially appliances, homes, and now, thanks to a software update pushed by the automaker this week, an electrical grid. Twelve of GM's EVs have this "bidirectional charging" capability, way more than US competitors' battery-electrics.

The potential for this tech, known as vehicle-to-grid charging, is exciting. An EV should not only be able to power a home through a days-long outage. It should also support the wider grid, helping utilities balance out electricity use during periods of high demand, like the moment the heat becomes undesirable and everyone turns on their air conditioning at once.

Even better, car owners can charge up their batteries on wheels when demand and prices are low, and discharge it into the wider grid when it's high—making them money in the process. The company can "turn every GM EV on the road into a distributed power resource," Sterling Anderson, the automakers' chief product officer, said at a company event in San Francisco on Tuesday. As US automakers work through policy about-faces that have upended EV sales projections in the US, forays into energy solutions like bidirectional charging give car companies opportunities to train their battery-making muscles.

Anderson also says that while V2G charging looks like an automaking side quest, it also helps GM answer the bigger and maybe even existential question of, "How do we make a car more valuable?" Maybe it can be really fun to drive. Maybe, one day, it can drive itself and run your errands. Or maybe, one day, it can make energy for you when it's plugged in in your driveway.

But as any parent knows, the chasm between potential and reality can gape. To use their cars to power their homes, drivers need to buy a $20,000 system from the automaker's four-year-old GM Energy subsidiary, and have it installed by someone who knows what they're doing. Also, they need to make sure their local utilities—and there are nearly 3,000 of them across the US—have worked with GM to not only OK the equipment, but to create programs that guarantee the owner money when their car helps out their whole region's electrical grid.

(GM says that homeowners generally get that $20,000 upfront price back after five or so years of use.) Though a quarter million Americans have GM vehicles with the bidirectional charging capacity, GM Energy's customers only number in the "thousands," according to the company. (A spokesperson declined to share more specific numbers.) Hundreds of thousands of GM electrics on the road right now can, with the right hardware and the local utility's support, feed excess power back into the grid. Why this matters: The integration of GM's electric vehicles with the electrical grid marks a significant shift in the role that EVs can play in supporting energy infrastructure.