PHOENIX (AP) — The Arizona Supreme Court has ended an effort to bar a proposal requiring the use of more renewable energy in Arizona from appearing on the November ballot.

In an order Wednesday, Chief Justice Scott Bales rejected an appeal that sought to prevent the measure from appearing on the ballot. The decision upholds a lower-court ruling that rejected arguments that backers of the measure hadn't gathered enough valid signatures from supporters to let voters decide the issue.

Earlier this month, the state said the campaign in favor of the proposal had gathered enough signatures to appear on the ballot. But opponents pushed forward with a lawsuit alleging that not enough valid signatures were collected.

The Clean Energy for a Healthy Arizona proposal, also known as Proposition 127, would require half the state's energy to come from renewable sources by 2030, compared with the current mandate of 15 percent by 2025.

A campaign opposing the measure is funded by Arizona Public Service Co.'s parent company. APS has said proposal would cause utility rates to rise and harm reliability.

A large amount of the renewable energy campaign's funding has come from a group backed by San Francisco billionaire Tom Steyer. Supporters of the initiative say Arizona hasn't taken advantage of its role as the sunniest state in the nation to develop more solar energy.

Matthew Benson, spokesman for a group opposing the ballot proposal, said in a statement that the group disagrees with the ruling, but knew from the start that challenging signature petitions would be an uphill fight. Benson said the group will now shift its efforts to informing voters about the adverse effects of the measure.

"Once Arizonans know the facts, we're confident they'll vote NO on Prop 127," Benson said.

DJ Quinlan, a spokesman for the Clean Energy for a Healthy Arizona campaign, said in a statement that the ruling is a failed attempt by APS to deny consumers a choice on clean energy. "This decision is great news for all Arizonans who want a cleaner, healthier environment for future generations," Quinlan said.