In Utah, Idaho and Wyoming more than 42,000 Rocky Mountain Power customers were participating in Blue Sky at the end of last year, a 10 percent increase over 2011.
"A growing number of Rocky Mountain Power customers are helping to build a stronger market for renewable energy through their voluntary participation in Blue Sky," Richard Walje, the Utah utility's president and CEO, said in a statement.
Under the Blue Sky program, consumers pay a premium on their monthly electricity bills $1.95 for each 100 kilowatt-hour block of Blue Sky energy they buy so they can be assured they are supporting the production of electricity from renewable resources.
Once a customer signs up, Rocky Mountain Power purchases "renewable energy certificates" from wind farms and other green power production facilities on their behalf. That guarantees electricity from those renewable resources is put on the regional power grid, reducing the need for non-renewable energy and benefiting the environment.
The federal agency's National Renewable Energy Laboratory noted that green power sales from the Top 10 utility programs exceeded 4.2 million megawatt-hours in 2012, up from 3.9 million in 2010. Wind energy represented approximately 85 percent of electricity generated from green energy programs nationwide.
A megawatt is enough energy to run the major appliances in 750 homes.
Despite the federal government's ranking, the Blue Sky program has its critics.
HEAL Utah, one of the state's leading environmental groups, believes PacifiCorp and Rocky Mountain Power should do more to expand the program.
"When we look around the country there are other programs that we like more," said Christopher Thomas, executive director of HEAL Utah.
Thomas said he would like Rocky Mountain Power to increase the amount of renewable energy it produces in Utah so it won't have to buy as many renewable-energy credits from out of state. He emphasized, though, that HEAL doesn't think Utahns should stop buying Blue Sky energy.
"The fact that we rank so high is really a reflection of the fact that so many Rocky Mountain Power customers like and want renewable energy," Thomas said. "But we get so little from that investment."
For Blue Sky information
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