(SALT LAKE CITY)-Rocky Mountain Power has notified state regulators that it wants to increase electricity rates by $67 million as of February 2010. The increase would mean an average Rocky Mountain customer would see their annual electricity bill go up by 4 percent, or about $2.70 a month. Rocky Mountain Power President A. Richard Walje recently told the Salt Lake Tribune editorial board that the utility needs the rate increase to help cover growing investments in power-generating facilities and transmission lines. The increase would be implemented by raising its monthly customer charge from $3$5.70.