PHOENIX — Arizona utility regulators are moving toward requiring electricity providers to draw significantly more of their power supplies from sources seen as environmentally friendly.

"Arizona's strength is the sun. This rule is going to help us play to our strength," Commissioner Kris Mayes said Thursday during a meeting on rule changes expected to be formally proposed next month.

After more than a year of studies and workshops, the commission is considering changes to a "environmental portfolio standard" that now requires electricity utilities regulated by the commission to get 1.1 percent of their power from solar or other renewable energy sources.

Under the proposal, the new minimum would be 5 percent by 2015 and 15 percent by 2023, with at least 20 percent of the required power coming from solar.

The changes also would increase monthly surcharges paid by customers. The surcharges are intended to let utilities recoup the higher costs of producing renewable energy.

Under the plan, the current 35-cent surcharge for residential customers would rise to $2. Surcharges for nonresidential customers would be higher; the largest power users would see their surcharge increase from $39 to $220.

Members of the all-Republican commission acknowledged the change will cost consumers but say the mandate is in the public's long-term interest.

Commissioner Mark Spitzer said he's seen seniors and children in Phoenix-area hospital emergency rooms because of respiratory conditions worsened by poor air quality.

"The status quo, you could argue, is a train wreck," Spitzer said.

Commissioner Bill Mundell said the current standard has already led to construction of solar generating stations in Springerville and Prescott and a biomass plant in Eager that burns plant waste.

However, Mundell said, "we have our work cut out for us to explain the long-term results."

Some environmental activists and advocates for producers of renewable energy said Thursday the commission was moving in the right direction but not far enough. A higher standard would help produce jobs, reduce pollution, save water and stimulate economic development in rural areas, they said.

"It makes good business sense," Valerie Rauluk of the Greater Tucson Coalition for Solar Energy said during a news conference before the commission meeting.

However, Commissioner Mike Gleason said the state has enough energy resources and doesn't need to increase what amounts to subsidies for selected industries.

"We're not in an emergency," Gleason said. "Nothing will be paid by the utilities. It's paid by the ratepayers."

Commission Chairman Jeff Hatch-Miller vowed that the commission won't repeat mistakes which the state made in providing effective and costly subsidies for solar energy equipment in the 1970s and, more recently, for alternative-fuel vehicles.

"This isn't about corporate welfare. This is about building an energy future for Arizona," he said.

Affected utilities have a mix of positions on the issue.

Ed Fox, an executive for Arizona Public Service Co., said the Phoenix-based company — the state's largest utility — can make the financial aspects of the commission's plan work.

However, an executive for Sulphur Springs Valley Electric Cooperative said the higher charges would be burdensome to the Willcox-based co-op's member customers.

Sierra Vista's public school system would pay an estimated $35,000 more annually because of per-meter surcharges while the city itself would pay $85,000 more, said Jack Blair, the co-op's chief marketing officer.

"Let's go slow on this and make sure we get it right," he said.

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Arizona Corporation Commission: http://www.cc.state.az.us