Hawaiian Electric Co. is expected to file a proposal Tuesday with the state Public Utilities Commission to cut nearly in half the net energy metering reimbursements offered to customers with rooftop photovoltaic systems.

The utility seeks to end the current NEM structure to make way for a new reimbursement model for rooftop-solar customers, said Leslie Cole-Brooks, executive director of the Hawaii Solar Energy Association, and Robert Harris, a representative of the Alliance for Solar Choice.

Customers now receive full retail credit for the excess net electricity sent to the grid from their rooftop PV systems. For January electrical bills the retail rate for Oahu customers is 29.5 cents per kilowatt-hour.

The utility will submit an application to the PUC requesting that the reimbursement rate be about 17 cents a kilowatt-hour, Cole-Brooks said.

The proposed reimbursement would change the credit that customers are receiving to a price structure closer to the base rate, Cole-Brooks said.

For wind projects the lowest PUC-approved base rate paid by HECO is 15 cents per kilowatt-hour to Na Pua Makani Power Partners. That rate was approved last month.

HECO declined to comment on the proposal ahead of a news conference scheduled for Tuesday.

Cole-Brooks said that while HECO can provide its analysis of net energy metering’s costs and benefits to ratepayers, the PUC is best suited to make the final determination.

"It is significantly less than what we are getting now," she said. "Our concern is we believe that the utility’s job is to have safe, reliable power and at reasonable cost. To make a decision on the NEM program, on whether or not it is fair, we believe is what the PUC does."

Accompanying the proposed changed reimbursement model for rooftop solar customers, the utility is expected to announce an increase in the capacity of rooftop solar that the grid can handle. Saturated areas are currently considered to have 120 percent photovoltaic penetration.

"They are recommending several changes, and some of them, including increasing the minimum daily load to 200 percent, is good news. It’s going to open up circuits," Cole-Brooks said.