In March 2022, Pacific Gas & Electric (“PG&E”) announced a partnership with General Motors to create a bidirectional electric vehicle (“EV”) charging program in California that would allow homes and small businesses to be powered in part, by charged EVs located on site. The principal supplier of electricity in northern California, PG&E and General Motors, announced a Summer 2022 pilot program to test electric vehicle-to-grid and vehicle-to-home systems to improve electric reliability and increasingly satisfy consumer demand.
The program is included among those prompted by the 2019 passage of California’s Senate Bill 676, which required the California Public Utilities Commission (“CPUC”) to lay out strategies and metrics to integrate EVs into the grid by 2030. In 2020, the CPUC announced its approval of a framework to integrate EVs as a grid resource. The PG&E bidirectional EV program is consistent with the CPUC framework.
Under PG&E’s proposed program, EV batteries would be used to supply electricity to serve local demand at its charging location via onboard AC power electronics and garage-installed DC smart inverters. The potential for reliability benefits appears to be promising. While house-installed energy storage batteries are fairly limited in their ability to discharge for long periods of time, electric vehicle batteries are large and capable of supplying electricity to a home or small business for several days.
Trials for the pilot program will take place in summer 2022. Testing will include the installation of EV chargers, including bidirectional hardware and communication software that will coordinate among the EV, the home network, and the PG&E grid. PG&E and General Motors intend to open the pilot to broader customer trials by the end of the year.
Beyond the electrical and installation challenges that are being studied through the pilot program, PG&E is also working to determine an appropriate price signal for the use of EV batteries to serve household demand and grid load. For instance, the value of a charged EV and the transportation it affords, must be accounted for in calculating the cost of electricity supplied to the home.
Because this program is only in the pilot testing phase, PG&E customers will not see any new rate programs until the program is submitted and approved by the CPUC. PG&E currently offers two Time-of-Use EV rate plans for residential customers: (1) Home Charging EV2-A, which combines the EV’s electricity costs with the home’s electricity usage; and (2) EV-B, which separates the EV’s electricity costs from the home electricity usage and involves the installation of a second meter. Any rate adjustments proposed by PG&E to create a bidirectional EV program will likely be effectuated through adjustments to these rate schedules.
For any questions on California’s bidirectional EV charging program, reach out to Michael Blackwell, Kirsten Large, or another member of our Energy and Natural Resources team.