EVs provide valuable grid services, but regulations are needed to ensure that the benefits are maximized, according to a report about a BMW/PG&E pilot program, BMW iCharge Forward.
BMW and PG&E partnered in a demand response program involving 100 BMW i3 cars in the San Francisco Bay area plus a solar-powered stationary BMW 2nd life battery system built from reused EV batteries.
During demand response events, BMW signaled drivers to delay charging through telematics embedded in the car. Drivers had the option of opting out of participating based on their charging and personal needs.
“Over the course of the 18 months, the program dispatched 209 demand response events totaling 19,500 kWh – equivalent to the electricity to power two homes for one year,” said David Almeida, program manager for the PG&E and BMW iChargeForward pilot program. “We knew that EVs could be an effective grid resource.”
The pilot demonstrates the possibility of scaling smart charging options to support the grid, he said. “As EV adoption continues to grow, the potential for these clean vehicles as a grid resource becomes more significant.”
However, new regulations are needed to maximize the benefits of EV-to-grid resources, said Rebecca Kiehne, BMW spokeswoman.
“Vehicles have the capability to serve as a grid resource right now. BMW i ChargeForward demonstrated that the existing communication system can be used to respond to utility signals for grid events,” she said.
Two measures needed
Two measures are needed to realize the benefits: First, regulations are needed that allow different parties to access the value that vehicles can create. Second, the grid value of vehicles should be clearly quantified, she said.
“Vehicles need new market aggregation rules that take into account the unique benefits that vehicles have as a mobile resource, as well as utility programs that spell out what the grid value is and how it can be accessed,” she said.
For each one-hour demand response event, BMW provided PG&E with 100 kW of grid resources by delaying charging for roughly 100 BMW i3 vehicles in the San Francisco Bay Area and also by using a stationary energy storage system.
Twenty percent of the resources provided came from the 100 EVs and 80 percent came from the energy storage system, according to the report.
For participating in the pilot, drivers received an initial $1,000, and rewards of up to $540 at the end of the program, based on how much they participated in surveys and demand response events, said Almeida.
Day-ahead and real-time events
During the course of the pilot—from July 2015 to the end of December 2016—the BMW resource provided grid services for both day-ahead and real-time events.
“The results indicated that there was no significant difference in the vehicle and battery contribution percentage between Real Time and Day Ahead across all DR events,” said the report.
The pilot program gleaned information about the size of future load reductions. If 20 percent of customers enroll in the program, and have an 8 percent participation rate and a contribution of 4.4 kW per vehicle, the potential load reduction of a single event in 2030 is about 77.6 MW, said the report. That’s enough to power about 58,000 homes in California.
In response to the results of the pilot, BMW received a grant from the California Energy Commission for a second phase of the project, working with 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,” said Almeida.
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