EVs Can Help Support the Grid, PG&E Study Confirms
David Wagman | June 09, 2017Newly released results of a pilot program by Pacific Gas & Electric Co. (PG&E) and BMW confirm the ability of electric vehicles (EVs) to support the energy grid through smart charging and demand response.
The study finds that using EVs as a flexible grid resource could lead to cost savings associated with operating and maintaining the grid as well as owning an EV.
During the program, which ran from July 2015 to December 2016, PG&E and BMW tested how managed charging of customer-owned EVs can benefit the grid during times of high demand.
(Read the final report on the pilot program.)
PG&E sent demand response signals to BMW requesting a load reduction on the grid of up to 100 kilowatts. BMW selected vehicles for delayed charging — up to one hour delay per day — and sent a signal to the drivers through their existing BMW smart phone application.
About 100 BMW i3 drivers located in the San Francisco Bay Area participated in the pilot and earned an incentive by offering flexibility in charging their EV. Participants could choose to opt-out of participating in events based on their charging and personal needs.
BMW supplemented the smart charging of these vehicles with a solar-powered energy storage system made from “second life” EV batteries — lithium-ion batteries from BMW MINI E demonstration EVs — as a back-up to support the grid during these demand response events as necessary.
The program dispatched 209 demand response events totaling 19,500 kilowatt-hours, equivalent to the electricity to power two homes for one year. On average, 20% of the grid resources were from the 100 participating EVs and 80% from the energy storage system. The amount varied based on the time of day the demand response events were called.
Based on customer research, 98% of participants indicated they were satisfied with the program and 93% stated that they are likely to participate in a similar program in the future if offered. Because the program was designed to run primarily in the background of customers’ lives, they were able to participate at high rates and felt little to no customer fatigue.
Based on the success of the BMW i ChargeForward pilot, BMW received a grant from the California Energy Commission to lead a second phase of the pilot with support from PG&E. The next phase will explore the ability to optimize charging events wherever the vehicle is charging — at home or on the go. The goal is to expand and test new smart charging functionality to generate greater benefits to the grid and to EV drivers.