A constant story in the United States is the battle between utilities and their customers who want to adopt solar and energy storage. But for at least one utility, there is no conflict.
Last week Vermont utility Green Mountain Power (GMP) announced that it had begun installation of Teslas Powerwall lithium-ion residential battery systems for its customers, as the first utility in the United States to do so.
The Powerwall is being offered under three arrangements: one where the customer owns and operates the battery, another where the customer owns the battery but allows GMP to access it for grid services, and a third where the customer leases the battery which GMP owns and utilizes.
Under the latter two arrangements the utility will use these batteries for peak shaving and other grid services. Under all arrangements the batteries can be used to supply backup power for these customers in the event of outages, and GMP notes that it will stop using the batteries in the event of a pending storm to allow for full customer use.
Green Mountain Power is known as perhaps the most solar-friendly of U.S. investor-owned utilities, and as early as 2008 began providing a US$0.06 per kilowatt-hour incentive to its customers who installed solar PV, on top of net metering. GMP Spokesperson Dotty Schnure says that the utility sees the benefit of solar and storage.
There is value for the system, in bringing generation closer to where the power is used, Schnure told pv magazine. We think this will help us have a more resilient, cost-effective future.
Customers who purchase the Powerwall and allow GMP access will receive a monthly bill credit of US$31.76. Customers may also lease the Powerwall for around $1.25 per day.
Schnure says that around 700 customers have expressed interest in the batteries. GMP initially ordered 500 Tesla Powerwalls, but has arranged for more batteries due to customer demand.
GMPs proactive attitude towards renewable energy is shared by the state of Vermont, which has the second-most aggressive renewable energy mandate in the nation. By 2032, utilities will be required to procure 75% of their electricity from renewable energy, including hydroelectric plants.