Rocky Mountain Power seeking to modify its net metering tariff

PacifiCorp, doing business as Rocky Mountain Power in eastern Idaho, is seeking to modify its net metering tariff to increase its Idaho territory’s “participation cap” from 714 kilowatts (kW) to 2,000 kW.

Power is generated by net metering customers as a means of offsetting all or part of their energy use, with excess energy fed back into the grid. Nearly all of Rocky Mountain’s distributed generation customers use residential and commercial rooftop solar applications. Rocky Mountain’s Idaho territory had only two net metering customers in 2007, but that number rose to 161 by the end of 2015. As a result, net metering generation rose to approximately 1,049 kW.

Financial credits are given to residential net metering customers who generate more power than they consume. Financial credits are given at the retail rate as it is established in the company’s residential rate tariff. According to PacifiCorp, however, paying the retail rate to net metering customers rather than a wholesale rate leads to subsidization from both the company and other non-net metering customers. Currently, that subsidy is not significant because enough net metering generation is not being done, but PacifiCorp warned that the issue must be addressed as distributed generation increases.

“While the subsidization may be relatively minor at this time as a percentage of total Idaho retail revenues, the company believes the issue should be addressed as soon as possible to minimize potential impacts on customers and set appropriate expectations,” Rocky Mountain Power said.

Rocky Mountain completed an analysis of the difference between the purchase prices paid to net metering customers and the wholesale prices for alternative power supplies in response to a commission order when the net metering program was established. According to the report, the company pays 10.34 cents per kilowatt-hour (kWh) to net metering customers on average compared to a wholesale rate at the Mid-Columbia Trading Hub of 2.47 cents per kWh.

During 2015, according to Rocky Mountain, a total of $44,446 was paid by the company for excess net metering generation that held a corresponding energy wholesale market value of $10,638. As a result of paying the full retail rate, the company warned, an uneconomic price signal was being sent to customers about the value of distributed generation.