REDDING, Calif. (AP) — State regulators are set to vote on a measure that would require California's major utilities to buy enough energy storage capacity by 2020 to power nearly a million homes.

The goal, in part, is to help develop the market for energy storage technology. That technology, which includes batteries, is currently being pursued by utilities, energy companies, startups and researchers, the San Jose Mercury News reported Wednesday. The California Public Utilities Commission is scheduled to take up the proposal at its meeting in Redding on Thursday.

Experts say the ability to store energy effectively would help the electric grid harness renewable energy sources that generate power sporadically. It would also build in excess capacity that could prevent service disruptions during events such as storms and wildfires.

They say California's regulations are being watched around the country.

"This is transformative," Chet Lyons, an energy storage consultant based in Boston, told the newspaper. "It's going to have a huge impact on the development of the storage industry, and other state regulators are looking at this as a precedent."

The utility commission's proposal would require Pacific Gas and Electric, Southern California Edison and San Diego Gas & Electric to acquire 1,325 megawatts of energy storage by 2020, with installations no later than the end of 2024.

It stems from a 2010 bill in the state Assembly.

In comments to the commission, the utilities expressed support for energy storage, although they raised concerns about the costs of the proposal given the nascent state of storage technology.

It's not clear yet how the storage mandate will impact ratepayers, the Mercury News reported.