General Motors and Pacific Gas and Electric Company are launching a pilot program that will allow electric vehicle owners to use their vehicles as a backup power source for their homes during a power outage.
They plan to test the two-way charging technology, which includes an electric vehicle and a vehicle-to-home (V2H)-capable charger, starting this summer at the PG&E Applied Technology Services facility in San Ramon, California. The pilot will involve collaboration on both bidirectional hardware and software that can manage energy flows between the EV, the home and the grid.
Following laboratory testing, the companies will conduct a field demonstration in a small subset of customer homes in the PG&E service area.
As more automakers like GM pursue aggressive electrification plans in the coming years, ways to store and reallocate energy supplies will need to be found to avoid overloading the grid. That's especially true in areas like California, where utility providers like PG&E have had to shut off power to hundreds of thousands of homes and businesses to prevent power lines from starting wildfires during high-risk weather conditions.
“We have the largest number of electric vehicles registered in our service territory in the United States, so as we look at that resource and its evolution, the genesis of it all was how do we make power outages invisible?” said Aaron August, PG&E vice president of business development, “You start looking at all these mobile batteries. How do we get them to actually help contribute to some of the different impacts that we're seeing through climate change and other climate-related events?
Other companies are also investigating ways to return power to the grid or home through EV batteries. Tesla's Powerwall, for example, uses the same batteries in Tesla vehicles to store solar power for backup protection, and Ford's new F-150 Lightning electric pickup truck will also be able to power homes in the event of a blackout.
“I can't speak for our competitors, but I can tell you that GM's pilot program with PG&E is comprehensive and focuses not only on physical charging hardware, but also software and network integration and conversion capabilities. AC-to-DC power required to ensure that bidirectional charging actually works automatically and gives our customers a consistent experience when needed,” said Phil Lienert, a GM spokesman.
Transforming alternating current (AC) into a direct current (DC) voltage, which can then be used to power electrical devices, is the current industry standard, which means that the technology that GM and PG&E propose will be more easily integrated in the path of the current network that feeds the batteries.
GM did not share which vehicles in its lineup would be used to test this technology, saying only that it would start with EV models it already has in production and ultimately intends to use its entire fleet. While GM has plenty of electric vehicles planned for the next few years, it currently only has a couple of electric vehicles in its portfolio, including the GMC Hummer EV and Chevrolet Bolt.
GM is expected to restart production of the Chevrolet Bolt EV, halted as the automaker replaces batteries in existing Bolts.
The pilot is in its early stages, so neither GM nor PG&E could share details about what the planned tests would look like in customers' homes. For example, the utility did not say whether it would selectively turn off power for certain customers, allowing them to use their electric vehicles as a backup generator.
Teams are working to scale the pilot quickly with the goal of opening larger customer trials by the end of the year, GM said.
Going forward, PG&E will use learnings from the GM pilot to advance networked vehicle technology, August said, particularly as relying on renewable energy can sometimes lead to situations where there is more demand than supply.
"Imagine a future where everyone drives an electric vehicle, and where that EV serves as a backup power option in the home and, more broadly, as a resource for the grid," said Patti Poppe, CEO of PG&E, it's a statement. "Not only is this a huge leap forward for electric reliability and climate resilience, it's yet another advantage of clean energy electric vehicles, which are so important in our collective battle against climate change."
