Is New Hampshire on the verge of battery energy storage history?
A small investor-owned utility in New Hampshire may be on the verge of regulatory approval for one of the most ambitious U.S. tests yet of utility-owned, customer-sited battery energy storage systems.
In the process, regulators and stakeholders of the DE 17-189 proceeding are wrestling with a question of vital interest to the rest of the 3,000-plus U.S. utilities: Should a utility own customer-sited storage or is it a distributed energy resource (DER) that should be left to private sector providers?
Utilities have already seen the benefits that large-scale battery energy storage offers in shaving peak demand, providing grid services, and making systems more flexible. There is a clear opportunity to use customer-sited battery storage in the same way. But the question of how far utilities can intrude into markets so far served by private sector vendors must first be answered.
Vermont goes first
The only major U.S. utility-owned, behind-the-meter (BTM) battery storage is the Green Mountain Power (GMP) pilot project, according to GTM Research Energy Storage Analyst Brett Simon. GMP, the dominant Vermont electricity provider, is installing 2,000 behind-the-meter Tesla Powerwalls that will provide dispatchable energy and other grid services to New England’s wholesale electricity markets. Customers pay a one-time $1,300 fee or a monthly $15 fee to participate.
New Hampshire’s Liberty Utilities wants state regulators to approve a pilot project of 1,000 utility-owned Tesla Powerwalls. They would be provided to customers for a one-time $1,000 fee or a monthly $10 fee.
Approximately 300 would be installed in homes along a circuit where Liberty wants to test the viability of a non-wires alternative to a distribution system infrastructure upgrade. The other 700 batteries would be available to customers who apply to participate in the pilot.
Like GMP, Liberty would use the BTM storage to reduce its customer base’s costs for power market peak demand charges and to provide other system services. Liberty would also use the pilot to introduce a new time-of-use (TOU) rate to support customer participation.
Private sector DER providers and the New Hampshire Public Utilities Commission (NHPUC) Staff say the pilot should not be approved. Solar and storage providers Sunrun and ReVision Energy argue Liberty customers would benefit more by working through the private sector. Staff argues the proposal is too costly and not technically workable.
Liberty wants ownership
“We believe the utility can do this just as well as the third-party providers,” Liberty Senior Rates and Regulatory Affairs Analyst Heather Tebbetts told Utility Dive. “Part of the pilot addresses a non-wires alternative program, and we believe utility ownership for it is appropriate. Since we will own a portion of the batteries, we felt owning all of them for the pilot was appropriate.”
The parties are now engaged in settlement talks. Several confided to Utility Dive they are optimistic about finding common ground. If they do not reach an agreement by early July, the debate will go to commissioners for a ruling.
The utility proposal
As the power grid takes on new challenges, like high renewables penetrations and the need for greater flexibility, residential storage can be “another avenue for utilities to expand their business models,” GTM Research’s Simon, emailed Utility Dive.
Liberty Utilities expects the 5 MW nameplate capacity of the 2,000 batteries to save its customers “about $693,000 a year in transmission costs,” according to its NHPUC filing. The savings will come in the near term by reducing local and regional peak demand period transmission charges.
Over the pilot’s proposed five-year period, Liberty will incur cost savings through use of batteries as a non-wires alternative, the filing adds. Through the pilot, Liberty expects to get a better understanding of “how batteries interact with the distribution system, how to efficiently utilize the stored energy, and the overall savings in avoided distribution system upgrades.”
The cost for each installation, including battery and software, is estimated at $7,000 to $9,000, Liberty reports. The utility will request cost recovery through rates in the rate case that follows deployment.