PHOENIX - Ignoring a threatened lawsuit, a House panel voted Tuesday to give lawmakers the power to approve - or veto - policies of the Arizona Corporation Commission.

HB 2789 is designed to overturn a ruling by the state Court of Appeals that the five-member panel has exclusive authority to require utilities to produce some of their power from renewable sources. It also would throw into question a separate commission ruling forcing utilities to conserve energy.

The 6-3 party-line vote by the Republican-dominated Government Committee came despite a warning from Paul Newman, one of the commissioners, that the legislation runs afoul of the specific constitutional authority of the commission to not only set rates but deal with related issues like renewable energy.

But Gary Pierce, the commission chairman, said he sees nothing wrong with the regulators sharing authority over setting policies with the Legislature.

Pierce, a Republican, conceded under questioning that the commission's own lawyers believe that the legislation runs afoul of last year's appellate court ruling, a decision that was upheld without comment by the Arizona Supreme Court.

And Newman, one of the two Democrats on the commission, predicted that any effort by lawmakers to intrude into what the courts have said is exclusive commission jurisdiction will end up in court.

Clint Bolick, an attorney for the Goldwater Institute, which mounted the unsuccessful legal challenge to the commission rules, argued that the appellate court got it wrong, and that a new legal challenge might bring a different result.

Central to the dispute are regulations first adopted in 2006 that require investor-owned utilities to generate 15 percent of their power from renewable sources by 2025. That includes solar, wind and geothermal.

These sources cost more than power generated from nuclear energy or coal-fired plants. Commissioners gave utilities permission to impose a surcharge to make up the difference.

While that surcharge is capped below $5 for residential customers, the amount taken from business and industrial customers is much larger.

A parade of business owners and lobbyists from companies that manufacture and install solar energy devices urged lawmakers to back off.

John McDonald, representing the Solar Energy Industry Association, told legislators they should not take up this legal battle solely because some people do not like the renewable energy standard and what he called the "small surcharges" on customer bills.

Bolick, however, said they were more interested in protecting a policy that increases their business.

And Rep. Debbie Lesko, R-Glendale, who is sponsoring the measure, said there's nothing small about the charges.

The bill, which now needs full House approval, wouldn't void the existing renewable energy and conservation requirements. Instead, it says any change proposed by the commission beginning next year couldn't take effect without legislative and gubernatorial permission.