With the sweltering days of summer behind us and New Englanders reluctantly turning their minds to winter storm season, it is worth asking how we can keep our electric grid running affordably and efficiently during both heat waves and cold snaps. Behind-the-meter energy storage is one solution that is showing increasing promise.
In-Home Energy Storage
Behind-the meter energy storage refers to when customers store electric power purchased from the grid or power generated themselves (such as from rooftop solar panels) in batteries installed in their homes. The market for behind-the-meter storage is growing rapidly due to decreasing costs and growing awareness. In addition to providing backup power to homeowners during outages, like a traditional generator, this storage can provide backup power for the grid itself.
Battery storage can also be combined with innovative electric rates. For example, time-varying rates could encourage customers to purchase power from the grid during periods of low demand and use energy stored in their battery during periods of high demand. This would lower storage users’ bills directly while reducing the use of expensive and polluting backup plants typically needed during times when temperatures surge or plunge. In turn, avoiding these expensive resources will cut energy prices for all customers.
Policies and Pilots
Many states are currently experimenting with adding battery storage to the grid to help reduce prices and integrate renewable energy sources that produce power intermittently. This wide range of pilots is providing valuable lessons for putting storage to good use. For example, Vermont’s Green Mountain Power (GMP) claimed it saved customers $500K during a heat wave this summer through its pilot of in-home batteries. During the hours of highest demand, the program allows GMP to withdraw energy stored in customers’ batteries instead of paying very high prices on the wholesale market. This year, GMP also expanded its pilot program to allow customers to purchase third-party storage devices. In New Hampshire, Liberty Utilities is proposing a similar pilot that would combine storage with time-varying rates to provide customers with incentives to use electricity during times of lower demand.
To support a future electric grid where consumers are empowered to produce, store, and use their own electricity, state policies should enable residents to own and operate batteries to the largest extent possible. Utility ownership of residential batteries can stifle the development of competitive markets and reduce customers’ flexibility in deciding how and when to deploy their power. Acadia Center will continue to advocate for programs that prioritize a customer-centered model, helping states pursue and expand programs like those detailed above.
Ellen Hawes is Senior Analyst for Energy Systems and Carbon Markets, working out of Vermont and New Hampshire. Her work focuses on energy systems, land use, and bioenergy.