Michigan Attorney General Dana Nessel is urging a federal appeals court to rule in favor of the Federal Energy Regulatory Commission in a dispute over energy storage.
FERC said last year that energy storage companies can sell their stored electricity to the open market on the electric grid, just like a gas- or coal-burning plant can.
Nessel supports the FERC decision.
But the National Association of Regulatory Utility Commissioners appealed, saying FERC was acting beyond its authority.
Jason Burwen is with the U.S. Energy Storage Association.
He says energy storage has the potential to reduce electricity costs for customers, because it increases competition, and he says energy storage can maximize renewable energy in cases where solar or wind create more energy than is needed at the time.
"Energy storage can bottle the sun and capture the wind for when you need it the most," says Burwen. "That is going to be increasingly important as various parts of the country move to higher and higher levels of renewables."
The utility commissioners group says FERC's decision denies states the ability to fully manage energy storage resources.
The Michigan Public Service Commission is a member of the national utility commissioners group. A spokesman for MPSC said in an email, "The MPSC is supportive of addressing barriers to energy. The Commission prefers to work collaboratively with FERC to ensure the full value of storage can be captured and so that storage is fairly compensated for the unique service it provides."
This story was updated to include the position of the MPSC on the lawsuit against FERC.