The Colorado House passed a key part of the state’s clean energy plan during a Saturday session.

House Bill 1313 is aimed at helping electric utilities transition away from old power generation to green energy sources. The vote was 40-22.

Republicans argued that the Democrats’ bill would hike rates for residential customers.

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“Retiring anything, especially coal plants, before the end of their useful life is going to cost money,” said Rep. Susan Beckman, R-Littleton.

Not so, replied the bill’s sponsor, Rep. Chris Hansen, D-Denver. Modernizing facilities and shifting to cheaper sources or energy ultimately will save money for ratepayers.

“We can do this transition and do it in a way that improves the health, safety and air quality of this state, and at the exact same time save money for customers,” he said.

The goal is to reduce carbon dioxide emissions by 80% by 2030 and 100% by 2050, based on 2005 levels.

The bill passed 40-22 and now heads to the Senate to start over.

Rep. Matt Soper, R-Delta, sided with Democrats in support of the bill. Democratic Reps. Adrienne Benavidez of Adams County and Donald Valdez of La Jara opposed it.

“(House Bill) 1313 is definitely a measured approach,” Soper said. “It’s an industry- and market-driven approach that definitely will have significant customer savings.”