Colorado Democrats slammed the door Wednesday on Republican plans to undo clean-energy policies adopted in recent years.
A Democrat-controlled Senate committee narrowly rejected three Republican proposals to lower consumer utility bills.
Democrats said they sympathized with residents paying steeper power bills but insisted the proposed changes would be short-sighted.
Republicans contended the clean-energy policies have hit too hard in a poor economy. Xcel Energy, which serves about 1.4 million Coloradans, has raised rates some 20 percent over the past six years -- a hike attributed in part to upgrading power plants.
"This body should not be in the business of heaping additional costs on struggling families," said Republican Sen. Shawn Mitchell, who sponsored a failed proposal to ratchet back a requirement that utilities get 30 percent of electricity from renewable sources such as wind and solar by 2020.
Colorado's renewable-energy standard, exceeded only by California, is commonly faulted by Republican politicians who say it improperly inserts government into the private energy market.
Democrats in charge of the committee swatted down Mitchell's idea and two other GOP proposals to reduce utility rates.
Those two bills would have instructed regulators with the Public Utilities Commission to put greater emphasis on ratepayer fees, and less emphasis on possible future energy costs, when considering utility rate requests.
Both were efforts to undo Democratic-supported changes to the PUC to promote alternative energies.
All three measures failed Wednesday with 3-2 votes.
The hearing dealt a blow to Republican campaign promises to try rolling back Colorado's turn toward clean energy in recent years.
Democrats on the State Senate, Veterans and Military Affairs Committee blasted the ideas as short-sighted. Sen. Rollie Heath, D-Boulder, took special aim at a proposal by Republican Sen. Steve King to forbid the PUC from considering potential future costs such as carbon taxes.
"We might as well hire 100 robots in here and roll the dice and see what the robots are going to do," Heath said. "It makes no sense to me at all."
Two former PUC commissioners who frequently criticize legislation promoting alternative energy testified that the Republican ideas put consumers first.
"Every effort must be made to keep the cost of electricity to a minimum," said former PUC member Carl Miller, who is now affiliated with Affordable and Reliable Energy Colorado, which promotes traditional fossil fuels. The group took out full-page ads in The Denver Post recently urging the Legislature to emphasize ratepayer costs.
Democrats weren't persuaded. Sen. Bob Bacon, D-Fort Collins, said he could not support changes that wouldn't confront the prospect of irreversible climate change.
"What is the stewardship of this generation at this time to make sure that doesn't happen?" Bacon asked.