David Quinn, Associated Press
Rocky Mountain Power is asking Utah regulators today for an $11.6 million decrease in customer electricity bills. The proposal would reduce a average household electricity bill by $4.08 per year.

SALT LAKE CITY — Rocky Mountain Power on Monday asked the Utah Public Service Commission for an $11.6 million decrease in customer electricity bills.

The request followed a review in which the utility determined the cost of fuel and electricity was lower than previously forecast.

The commission approves customer prices based partially on the expected costs of fuel and electricity purchased on the open market. Rates are subsequently adjusted depending on whether the actual costs rise or fall. Similarly rates are also adjusted for the sales of Renewable Energy Credits that are sold on the open market with revenues credited to customers in order to lower their bills.

The utility determined actual costs of fuel and electricity purchases last year was slightly less than expected. The company also found customers received credit for more than the actual amount generated by renewable credit sales.

As a result, Rocky Mountain Power has proposed a 0.56 percent decrease in electricity rates, where an average customer would reduce their annual electricity bill by $4.08. The utility is asking the commission to make the rate changes for the renewable credit sales beginning June 1 and changes for the energy costs on Nov. 1.