But by reducing their electric bills, such residential customers are avoiding their share of the utility's fixed costs associated with electrical transmission and customer service, according to Joelle Stewart, RMP's cost-of-service manager.
"All this infrastructure is necessary to service these customers. These costs do not go away with the growth in net metering," Stewart told the PSC, the three-member panel that sets electrical rates.
This assertion, which is hotly disputed by environmental groups and solar customers, was echoed by Daniel Gimble of the Utah Office of Consumer Service.
The consumer advocate recommended charging $1.54 per kilowatt of generating capacity in contrast with the flat fee the utility proposes so those with smaller systems would pay less.
Salt Lake City Mayor Ralph Becker is among a cast of local officials asking the PSC to more fully consider the benefits of net metering before authorizing any fee that would discourage its growth, which many see as vital to a cleaner, more secure energy future.
The city's sustainability manager, Tyler Poulson, said a similar fee authorized for an Arizona utility last year led to a 40 percent drop in new solar installations. He claimed solar users may help the grid by helping to ease future load growth.
"But there are other benefits in terms of avoided environmental regulation, and reduced reliance on finite fossil fuels and price volatility associated with that, air quality and quality of life issues," Poulson said Monday on Trib Talk, the Tribune's daily online video chat with Utah newsmakers.
An RMP spokesman countered that these benefits are far from certain.
"There isn't general agreement on how to calculate environmental or societal benefits. More importantly it's unclear how those benefits are factored into the price of electricity," Dave Eskelsen said.
The PSC hearing continues Tuesday with additional testimony from experts with the Sierra Club and other "intervenor" organizations. The commission will field public comments at 5 p.m. Opponents of the fee will stage a 4 p.m. rally in front of Salt Lake City's Heber Wells Building, where the hearing is taking place this week.