- Pacific Gas & Electric (PG&E) and General Motors (GM) on Tuesday announced a pilot aimed at using electric vehicles as on-demand home power sources in the utility's Northern California service area.
- The two companies plan to test bidirectional charging technology – which would allow customers to send power from their vehicles to, for instance, a home – thereby enabling EVs to power essential home needs, while also contributing to electric reliability in PG&E's footprint.
- "We see this as... electric vehicles becoming mobile power sources or mobile batteries, if you will, offering greater energy reliability and resilience," Aaron August, PG&E's vice president of business development and customer engagement, said during a media briefing, adding, "this is a huge shift in the way we're thinking about electric vehicles."
California passed legislation in 2019 that required the state’s Public Utilities Commission to lay out strategies and metrics to integrate EVs into the grid by the end of the decade. In late 2020, the agency approved a decision laying out a framework for vehicle-grid integration in the state.
The biggest hurdle to implementing bidirectional charging will be getting the price signals right, Michael Colvin, director of regulatory and legislative affairs at the Environmental Defense Fund, said in an email.
“It’s relatively easy for the utility to send a price signal to the vehicle to “not charge”, but [it's] much harder to say “we need your power from your vehicle,” Colvin added.
California is aiming to ensure that 100% of new passenger car and truck sales are zero-emission by 2035. EVs play an important role in the state's decarbonizing goal – currently, the transportation sector contributes almost 40% of its greenhouse gas emissions.
"EVs are already providing a ton of benefits to consumers but the value proposition of EVs in general [is] continuing to build and expand. We see this expansion as being the catalyst for what could be the most transformative time for two industries – both [the] utility and automotive industry," August said.
The companies intend to test a "vehicle-to-home" capable EV and charger by this summer, including the use of bidirectional hardware and software-defined communication protocols that will automatically coordinate among the EV, home and PG&E's network. After that, the pilot will focus on testing vehicle-to-home interconnections in a small number of customer homes. PG&E and GM hope to open the pilot to larger customer trials by the end of the year.
Given the early stage of the pilot, the utility was not yet able to provide detailed information on how much it expects to spend on the project, or how many homes will be included in the pilot.
"Not only is this a huge advancement for electric reliability and climate resiliency, it's yet another advantage of clean-powered EVs, which are so important in our collective battle against climate change," PG&E Corp. CEO Patti Poppe said in a statement.
The pilot could also offer valuable lessons on bolstering electric reliability and resilience in PG&E's service territory. As a simple rule of thumb, an average California home uses about 20 kWh of electricity a day, Rick Spina, vice president of EV infrastructure at GM, said. A fully charged Chevy Bolt, meanwhile, has around 60 kWh of power.
"You basically can easily say that if you really pushed it hard enough, you could run about three days of an average California house off of a fully charged Bolt," he said.
California regulators have been paying particular attention to the ways in which demand response can support the grid after utilities in the state were forced to initiate rotating blackouts during a record-breaking heatwave in the summer of 2020. In such a situation, a charged EV could offer a few days of potential power, and utilities could also manage EV charging during certain times of day so as to smooth out grid conditions, August noted.
"There's a variety of ways to actually orchestrate when these vehicles are charging or how they're going to be putting power back to the home," August said.