State utility regulators have approved two first-in-the-nation home energy storage programs for Green Mountain Power customers looking to own or lease a backup battery.
The utility says that the programs will allow participating customers to improve the reliability of their power supply during storms.
GMP also projects the programs should save all its customers more than $5 million over 10 years. That’s because the utility will draw on stored power in the batteries during peak demand times when electricity is priciest — and apt to be the least green.
Under one tariff approved earlier this month by the state’s Public Utility Commission, GMP customers can sign 10-year leases for two Tesla Powerwall batteries for $55 a month. A single Tesla Powerwall battery costs $6,500.
In a second program that was approved, customers install their own batteries and receive up to $10,500 in exchange for allowing the utility to draw on the stored energy.
The approvals come after some in the renewable energy sector raised anti-competitive concerns about the GMP-owned Tesla battery program. The two-year offerings, which customers can sign up for starting this Friday, are capped at 500 customers a year.
“Team Vermont is again leading the way in home energy storage, and we’re so glad to be able to help grow this green economy by working together with our customers and partners in energy innovation in Vermont,” said Mari McClure, GMP’s president and CEO, in a prepared statement.
The utility has previously piloted similar home energy storage programs, which it says have saved customers hundreds of thousands of dollars and provided over 10,000 hours of backup power during last year’s Halloween storm.
The Department of Public Service opposed both tariffs, arguing that they place a “disproportionate share of risk” on non-participants if the savings don’t materialize and were unfairly priced. The department, which supports efforts to roll out more home battery storage systems, wanted the utility to submit a performance-based tariff for both GMP and customer-owned batteries.
Olivia Campbell Andersen, executive director of Renewable Energy Vermont, said the programs represent “the most significant investment” in home energy storage by any electric utility nationwide.
“We’re glad that the PUC saw the very obvious benefit, and the sense of an actually urgent need for a resilient energy system,” she said of the “bring your own device” program, which REV helped develop.
REV had originally asked the commission to deny the Tesla Powerwall tariff, saying it gave an unfair advantage to one battery company. Campbell Andersen said that the group feels that the final tariff, which incorporates some changes in response to the department’s and REV’s concern, is an improvement over the pilot as it will allow customers to choose what local company they would like to have install the Tesla battery.
The utility, which provides electricity to approximately 266,000 customers, has contended that running both programs will provide more options for customers looking to economically install home backup batteries. Liberty Utilities in New Hampshire has modeled its home Tesla battery pilot programs after Green Mountain Power’s efforts.
Over the past few years, Green Mountain Power also has started pairing utility-owned solar installations with large battery storage systems.
