FROM INDIANA PUBLIC BROADCASTING

Nearly half of all the solar installed in Indiana came online last year, mostly from the state’s utilities. The state also made big waves in clean energy during the first quarter of this year.

Indiana added the third most solar of any state in the first quarter of this year. It also quadrupled its battery storage — mostly due to a new, 200 megawatt facility at AES Indiana’s Petersburg Generating Station in Pike County. The utility plans to convert the coal plant to natural gas and hopes to finish another solar and battery storage project in the county next year.

Indiana Public Broadcasting reports that these stand-alone batteries allow utilities to buy energy off the grid when it’s cheap and store it for their customers or sell it back to the grid. Because that could be any combination of wind, solar, gas, and coal — it’s hard to say if the energy stored is particularly green.

Mallory Duncan, communications director for AES Indiana, says:

“It changes every day, every hour, every month, where that energy comes from.”

But the American Clean Power Association says even if batteries aren’t paired with solar or wind, their flexibility can help make all the energy sources on the grid run more efficiently. The association also says battery storage is becoming cheaper and more efficient — which makes it more attractive to utilities.