OUC now offers a rebate of up to a $2,000 to residential customers who supplement their solar photovoltaic systems with a battery. Battery storage can serve as a backup power source during outages, extended cloud cover and periods of darkness.

The incentive is available only to OUC residential solar PV customers, including those with OUCollective Solar, and it applies to batteries with at least 8 kilowatt hours of capacity and a 10-year defect warranty.

To apply for the rebate, applicants must submit a copy of the manufacturer’s specification, electrical one-line diagram, proof of warranty, proof of purchase (must be submitted within six months of purchase, and the purchase must have been made on or after Nov. 1, 2019), and an invoice (if the battery was installed at the same time as the solar system, the battery price must be itemized separately). There’s a limit of one rebate per customer or service address. Customers may install a battery at the same time as they install a solar system, or they may retrofit an existing solar system with a battery at a later date. The battery rebate is not part of OUC’s preferred contractor network offering.

Among the batteries available is the 13.5-kWh Tesla Powerwall 2, one of the more popular units in OUC’s electric service territory. The Powerwall 2 measures 43.3 inches long by 29.7 inches wide and 6.1 inches deep and weighs 276 pounds. It can be mounted on the floor or wall, indoors or outdoors. Tesla lists the basic cost of a two-Powerwall battery system at $14,000, excluding installation.

Battery storage charged by solar energy is eligible for a federal tax credit of 30 percent, but only if you own the solar PV system, which must be co-located with the battery. To claim the full amount of the investment tax credit the battery must be charged by renewable energy 100 percent of the time. Click here for more information on tax credits for batteries hooked up to renewable energy systems.

The credit falls to 26 percent in 2020 and 22 percent in 2021 for owners of new residential solar installations. Currently the tax credit for residential solar installations is set to expire in 2022.