With a quarter of all solar project proposals in the US including batteries, transmission grid operators across the country are taking a variety of steps to evaluate the role that can be played in wholesale electricity markets by hybrid power plants – defined as generation coupled with energy storage.

Revisions aimed at enabling energy storage’s participation in wholesale markets, proposed by New England’s Independent System Operator (ISO) have been accepted by the Federal Energy Regulatory Commission (FERC), effective 1 April this year.

Transmission system operators in the US have begun making their moves to accommodate energy storage into their wholesale markets, with New England ISO and Southwest Power Pool both making filings in the past month.