Early results from the first electric cooperative test of an electric-vehicle-to-grid charger show promise that such systems can help reduce peak demand and save members money.

Roanoke Electric Cooperative in Ahoskie, North Carolina, is testing a device from Fermata Energy that can charge an EV and allow power from the car’s batteries to directly feed a building or the electric grid. This bidirectional, or V2G, capability could help utilities avoid peak power costs by tapping into the lower-priced energy stored by an EV during nighttime or off-peak hours.

“The overall goal is to stabilize our rates, become more efficient as a utility and prove new with ways to save our members money,” said Curtis Wynn, president and CEO of Roanoke Electric, which serves about 14,000 members.

Fermata Energy asked Roanoke Electric last year to help test its FE-15 charger using the co-op’s two leased Nissan LEAF EVs. The device can draw up to 111.6 kilowatt-hours in V2G capacity from the vehicles’ 62-kWh lithium ion batteries.

The system shaved 3.8 kW off the December peak at the co-op’s headquarters, saving about $36 in avoided demand charges, and 11 kW off its January peak, saving another $105, said Anita Knight, Roanoke Electric’s manager of engineering.

“It’s a very small percentage based on average demand on a monthly basis, but it is proving the concept,” she said.

Wynn said the co-op will use the test results to inform an upcoming commercial EV rate design study that will enhance its current pilot residential EV rate. The ultimate goal is to determine how to pass on savings and create EV incentives for members.

A post-pilot report will look at how the charger might be better used with commercial members who decide to convert their fleet to EVs. Wynn said he is happy to share the results with other co-op leaders.

Roanoke Electric is collaborating with and gaining technical assistance from Advanced Energy, Clean Energy Works, North Carolina State University’s Clean Energy Technology Center and the Environmental Defense Fund, which are equally interested in the potential value of the V2G technology.

Fermata Energy’s bidirectional charger is the first in the country to be certified by Underwriters Laboratories, the global science safety firm.

“Being in a rural area and at the forefront of this innovative technology is an interesting dynamic,” said Wynn. “Great partnerships make a difference for us.”