The Salt River Project (SRP), an electricity and water cooperative in Arizona, launched new incentives for energy storage on May 1. The program can be signed up for here.

The utility is offering up to $1,800, in increments of $150 per DC-kWh, for an energy storage project installed at a home within the utility load zone. Customers will be required to pay a monthly service charge of $32.44 as part of the ‘Customer Generation Price Plan’ that is specifically designed for those using solar power.

As of the launching of the incentive on May 1, there were 4,500 spaces available for the program. Currently, on the above sign up page, there are only 3,401 spaces left in the program, meaning that roughly a quarter of the reservations have already been taken.

The lawsuits that led to this incentive started when SRP implemented a rate structure that imposed discriminatory charges its customers who own pv systems, as one of the few times that a utility has imposed a demand charge on residential customers in the United States. In 2015 a judge ruled that the utility had in fact acted illegally as a monopoly in imposing this targeted rate structure.

In early March, with a Supreme Court case pending, the board of the electricity utility voted to approve the details of a settlement that included not only this energy storage incentive, but also the purchase of a massive 25 MW battery from Tesla.

At current rates, this incentive will be gone by the end of the month. And with recent studies suggesting 74% of residential solar power buyers are also interested in energy storage, this appears to be part of a national trend.