Image Source: Tebbetts, H. (2017). NHPUC DE 17-189, Direct Testimony of Heather M. Tebbetts.
This holiday season Liberty Utilities announced plans to install 1,000 battery systems (5 Megawatts) in 1,000 residential homes to reduce short-term transmission costs and study potential for long-term energy storage benefits. Liberty’s outline is the first serious proposal to bring energy storage to the Granite State.
The company’s proposal, much like its author Heather Tebbetts, is candid and to the point, stating it is time for utilities to “move beyond simply selling customers more electricity.”
In the proposal, Tebbetts discusses the “Transition to a Modern Utility” through “investment in a modern and flexible distribution system, which is able to manage loads, provide real-time information, and interconnect distributed generation resources in multiple locations.” Tebbetts warns that utilities failing to embrace energy storage “will be left behind like the landline phone companies,” holding millions of dollars of stranded, useless assets as technology passes them by.
Energy storage can allow utilities to lower grid costs by deferring upgrades to distribution substations and reducing transmission costs through reductions in peak system usage.
“The near-term goal… is to reduce… transmission charges. The long-term goal is to study the effects of batteries on the distribution system and the effects on transmission costs” over a five year period, reads the testimony. Liberty estimates the project will save customers about $693,000 per year in transmission costs.
Customers hosting a battery and participating in the program will adopt a three-part weekday time-of-use (TOU) rate, under which electricity will be priced higher between 2pm and 7pm (critical peak), moderately between 7pm and 8am (on-peak), and lower between 8am and 2pm (off-peak). The batteries will allow customers to shift their reliance on the grid to off-peak hours when electricity is cheapest.
The Public Utility Commission (PUC), whose approval is required for the project, began the regulatory process with a prehearing conference on January 4th. Liberty plans to begin battery installations in November 2018. Other intervenors in this proceeding may contend that it is not in the best interest of consumers to have utilities own storage behind their customers' meters and could hurt this growing, competitive market.
New Hampshire’s other two investor-owned utilities, Eversource and Unitil, have announced no plans to utilize batteries to reduce customer costs.
Tebbett’s testimony, a mere 24 pages (infinitesimal by PUC standards) and written mostly in plain English (as opposed to the usual PUC legalese and technobabble), is surprisingly readable and can be accessed here. (There are, however, more complicated and detailed appendices). Liberty will be submitting revised testimony on February 9th.
Liberty provides electricity service for roughly 44,000 NH residents, primarily in Sullivan and Grafton counties, but also in four Rockingham county communities.