Liberty Utilities Proposes Residential Electricity Storage/Battery Pilot ProgramJul 25, 2018
Liberty Utilities is seeking the New Hampshire Public Utilities Commission’s approval of a battery storage pilot program in which the company would buy and install approximately 1,000 batteries having an aggregate electricity storage capacity totaling 5 megawatts. Under this program, the batteries and related equipment would be installed at the homes of participating residential customers who would pay a monthly charge to defray some of the storage system costs. Participating customers would also be billed under a new time-of-use rate instead of a fixed cents per kilowatt hour rate.
The near-term goal of the battery program is to reduce transmission costs. By using battery-stored electricity during peak demand periods, Liberty will be able to reduce its coincident peak. The company estimates that if the batteries are fully utilized, transmission cost savings will total approximately $693,000 annually. Because the transmission rate is reconciled annually, customers will receive the benefit of lower annual transmission charges. The batteries will also help Liberty avoid the cost of a second “feeder” or power line in the West Lebanon area. The estimated cost of this feeder line is $644,000 which would be passed along to Liberty’s customers if the line was installed.
Other program benefits include the customer’s ability to use the batteries as backup generators during short-duration power outages caused by storms or downed poles and wires. Customers will have access to battery capacity except when a peak demand is predicted for the following day. At those times, Liberty will control the batteries to ensure they are charged and ready for dispatch during the peak period. Liberty will also notify the customer that a peak may occur the next day and that the customer’s access to the battery will be limited. On the peak day, the company will monitor conditions and assess when battery discharge is needed. Customer load will be offset by the discharged battery, and any capacity not offsetting customer usage will be discharged by Liberty to the grid.
The battery storage pilot program’s long-term goal is to study the effects of the batteries on customers, the distribution system and transmission costs. The program will provide data concerning customer behavioral changes associated with time-of-use rates, if any, as well as customer satisfaction with increased service reliability. The pilot will also study the effects of the batteries on the electric distribution system and impacts on transmission charges. Liberty believes that the pilot program -the first of its kind in New Hampshire- will facilitate future development of distributed energy resources, thereby transforming the manner in which electricity is currently delivered to end-use customers.
The pilot program would be marketed first to residential customers in the West Lebanon area to address that region’s expected load growth and need for system upgrades. If the company cannot enlist enough customers to install batteries in the West Lebanon area, the program would be made available to residential customers in other communities where Liberty operates, including: Acworth, Alstead, Atkinson, Bath, Canaan, Charlestown, Cornish, Derry, Enfield, Grafton, Hanover, Langdon, Lyme, Marlow, Monroe, Orange, Pelham, Plainfield, Salem, Surry, Walpole and Windham. More information about this program may be found at: http://www.puc.state.nh.us/Regulatory/Docketbk/2017/17-189.html.
About the Author: Susan S. Geiger