Power companies and environmental groups are gearing up for a fight over a bill to change how customers are billed for solar power.

Customers now get an offset on their bills if they generate their own electricity through solar panels or other renewables. Utilities argue those credits mean higher charges for everyone else to make up for them. The bill would trim the credit from the retail power rate to the wholesale rate, giving customers credit for the power they generate but not for the transmission costs. 

Jodi Perras with the Sierra Club contends that creates the opposite problem, allowing utilities to charge everyone else for power they didn‘t produce. Indiana Energy Association president Mark Maassel says if the credits aren‘t adjusted, falling prices for solar equipment will make the current system unsustainable and force rate hikes.

Environmental groups also object to a provision allowing utilities to seek a flat charge on customers‘ bills instead of charging purely for usage. Maassel says the flat charge would lower the cost per kilowatt hour, so that overall bills remain steady. He says the change would better reflect utilities‘ fixed costs in wiring customers for electricity.