Batteries on wheels: General Motors and SDG&E look at EVs as an energy source

An increasing number of car makers are staking their futures on milliions of drivers buying electric vehicles.

They’re also envisioning electric vehicles, or EVs, not as mere modes of transportation but as miniature battery-storage centers on wheels — and that may lead to a different way of thinking about the auto industry and, by extension, the electric grid and the utilities that deliver power to their customers.

General Motors and San Diego Gas & Electric recently announced an agreement to look at the feasibility of integrating electric cars and trucks into the power system to help make the grid more resilient and reduce the impacts of blackouts on homeowners.

“We connected with GM, one thing led to another and opened it up an opportunity for us to collaborate and figure out ways that we can develop this nascent technology,” said Miguel Romero, SDG&E’s vice president of energy innovation.

Progress hinges on the bi-directional charging capabilities of EVs. That is, charging that goes two ways.

For example, taking electricity stored in an EV’s battery and sending it to the grid, especially when the power system is under stress. That’s called “vehicle to grid,” or V2G for short.

Closer to home, it can mean powering your household with the electricity stored in your EV — especially when there’s a power outage affecting your neighborhood. That’s called “vehicle to home,” or V2H.

Taking the technology a step further, there’s even V2X, which means “vehicle to everything,” that would include applications such as synchronizing data for things like speed and direction of travel to avoid traffic jams and greatly enhance road safety.

“As GM continues on its journey towards an all-electric future, expanding the capabilities of EVs represents a significant opportunity to help strengthen grid resiliency and mitigate the impact of disruptions,” Travis Hester, GM’s vice president of EV Growth Operations, said in a statement.

GM and SDG&E will also explore creating virtual power plants — that is, taking a collection of energy resources (including EVs), interconnecting them and using cloud-based software and artificial intelligence to enhance power generation, or even trade or sell power on the electricity market.

The collaboration grew out of each company taking part last year in a U.S. Department of Energy memorandum that brought together national laboratories, state and local governments, utilities, and private companies to explore how to incorporate bi-directional charging into energy infrastructure.

“Bi-directional charging holds tremendous potential for increasing the country’s energy security and grid reliability in addition to supporting economic opportunities for communities throughout the nation,” Rima Oueid of the Department of Energy said when the GM and SDG&E deal was announced.

Leveraging electricity from EVs may well prove to be an opportunity waiting to happen. According to research from UCLA professor Donald Shoup, typical passenger cars are parked for 95 percent of their useful life.

Part of the fleet of eight electric school buses in the Cajon Valley Union School District use vehicle-to-grid technology.

(Pat Hartley/The San Diego Union-Tribune)

Last summer, SDG&E and local tech company Nuvve rolled out a pilot project at the Cajon Valley Union School District in which a fleet of eight all-electric school buses successfully deployed V2G technology.

Each bus has up 210 kilowatt-hours of battery capacity, which is five times more than a typical EV. The buses typically charge overnight when electricity prices are low.

After the buses pick up and drop off students and drivers complete other chores, the batteries quickly get recharged and can then send electricity back to the grid.

“This is a platform that is able to aggregate vehicles across multiple sites and make them act like a big battery, basically,” Nuvve CEO Gregory Poilasne said at the time.

The agreement between GM and SDG&E is in its early stages and the two companies recently conducted remote discussions. The deal does not involve spending ratepayer dollars.

Should the entire transportation sector become fully electrified, Romero of SDG&E said the hope would be to tap into the energy stored by light-duty and heavy-duty vehicles and provide grid reliability and resiliency.

“That means we (wouldn’t) have the need to maybe build a power plant or build a transmission line, for example,” Romero said. “This is obviously a big vision that would ultimately result in economic benefits for everyone.”

A 2024 Chevrolet Silverado RST in a residential home garage with a vehicle charger.

(General Motors)

GM is also working with other utilities on separate efforts, including a V2H pilot project with Pacific Gas & Electric — the largest investor-owned utility in California.

The company recently launched a new division called GM Energy that will focus on fusing electric cars with the grid applications such as dedicated home backup power and a network of charging stations.

GM intends to become a leader in the global EV market. The company plans to stop producing vehicles with internal combustion engines by 2035 and vows to introduce 30 all-electric models by 2025. Those attending the recent San Diego International Auto Show saw GM’s latest EV entry, the all-electric Chevy Equinox, with a starting price of around $30,000.

Seeking to reduce greenhouse gas emissions, California policymakers have set a goal to derive 100 percent of the state’s electricity from carbon-free sources by 2045, if not sooner, and Gov. Gavin Newsom has issued an executive order banning the sale of new gasoline-powered passenger cars by 2035.

The EV transition faces some challenges, though.

Among them are concerns about whether the materials (such as cobalt, nickel, lithium) that go into batteries can be developed at a pace to keep up with the dramatic increase in EV adoption that’s anticipated.

Toyota may have kicked off the clean car movement when the Prius made its U.S. debut in 2000 but the company’s president made headlines last month when he said there is a “silent majority (that) is wondering whether EVs are really OK to have as a single option. But they think it’s the trend so they can’t speak out loudly.”

Talal Shamoon, CEO of Intertrust Technologies, a Silicon Valley software tech company that partners with global energy companies, said it’s crucial for bi-directional technologies to integrate smoothly.

“At the end of the day, you want to flip the switch and get the electricity, regardless of who stored it and who made it, so it’s very important that GM and the power company down there (SDG&E) are working together,” said Shamoon, who is not affiliated with the GM-SDG&E agreement. “This is a good experiment, but this stuff’s only going to succeed if the distributed energy technology works seamlessly, regardless of the vendor.”

It’s complicated and sounds a bit sci-fi, but Shamoon is confident that applications like virtual power plants will come quickly.

“The technology that’s required to make it work is already out there. It’s what made the internet a consumer product,” he said. “And when people start thinking of grids as networks and the locomotion of electricity in the same lens as the locomotion of data, this problem would solve itself a lot sooner than people think it will. And it’s going to be good for electricity, it’s going to be good for consumers and it’s going to be great for the planet.”