TEMPE — The outcome of the Arizona Corporation Commission race in November could determine whether there will be more nuclear power plants in the state — and possibly even new coal-fueled generators.

At a debate Monday, all three Republicans said that nuclear needs to remain one of the options for the state to meet its future demands.

“In order for the state to grow and sustain itself, we must have reliable electricity,’’ said Barry Wong. “We need to support a balanced portfolio ... whether it’s from coal generation, nuclear, natural gas or renewables.’’

And Marian McClure said coal in particular cannot be ignored.

“It is still the least expensive,’’ she said. McClure also said that with “scrubbers’’ to remove smokestack pollutants “there is very little emissions that are harming your environment.’’

But Paul Newman, one of the Democrats running for the three open seats on the panel, said the regulators need to be cautious when proceeding down that path.

“We need diversification,’’ he said. “But there are some problems, big problems, with nuclear expansion.’’

Newman said the Nuclear Regulatory Commission, which would have to approve new plants, has called the design for the next generation of nuclear plants is “problematical at best.’’

“That means a long delay for nuclear development,’’ he said.

The other Democrats, running as the self-described “solar team,’’ also questioned expanding those two sources of power in Arizona.

Sandra Kennedy said solar and wind should be the primary sources of new power, with new natural gas power plants “a distant third.’’

Kennedy acknowledged that power from “renewable’’ sources currently is more expensive. But she predicted that the cost advantage of both nuclear and fossil fuels would disappear by 2015.

And Sam George even wants to accelerate the current mandate on utilities to generate at least 15 percent of their power from “renewable’’ sources by 2025.

Some of the debate took on partisan tones as the Democrats were critical of the current five-member commission, composed entirely of Republicans.

On one hand, it was the Republican-controlled commission which gave that renewable energy mandate final approval in 2006. But

George complained that it took five years from when the idea was first discussed to make it happen.

There also were marked differences in the level of regulation each side believes is appropriate.

“Our future could be one of higher taxes on energy and more regulation of renewable energy industries, including solar, which will slow our economic growth, hamper innovation and make our country less clean,’’ said Bob Stump. He said a better alternative is when “innovation arises from a healthy economy based on economic liberty.’’

Wong said government intervention is appropriate only when private companies and a free market do not work. “However we must tread carefully on regulation as well so as to not overregulate ... which could also stifle and minimize market growth and market entrepreneurship.’’

George, however, said the state cannot rely on the private sector to deal with issues like climate change, which is why he wants to mandate alternate energy sources. He called that “a real crisis which is greater than any war.’’

And Kennedy said the commission needs to protect ratepayers.

“Who’s going to look after the consumer when the Corporation Commission basically is an agency that really looks after the big guy,’’ she said. “We just really need to return the power to the people.’’

All the candidates had some questions about allowing utilities to pass along at least some of their advertising costs to ratepayers.

George said utilities have used consumer dollars to conduct “image campaigns’’ on renewable energy. But he said the reality is that less than 1 percent of all power used in this state comes from alternate sources.

“When it comes to advertising, I’m still at a loss to understand why a monopoly needs to advertise in the first place,’’ said Stump. “We don’t have a choice of choosing between utilities.’’

But Joe Salkowski, spokesman for Tucson Electric Power, said the advertising his company does with ratepayer dollars is designed largely to inform customers about incentives and other programs

designed to get customers to install solar devices — part of the commission mandate to boost solar generation in the state. And he noted that spending has been approved by the Arizona Corporation Commission.

Arizona Public Service spokesman Marty Shultz echoed a similar sentiment, saying the company uses commission-approved funding to promote conservation and safety.

McClure said she would use her background in reading financial reports to ensure that any rate hike requests include money for only “appropriate’’ advertising.