Just two years ago, the president of Duke Energy Florida said the Sunshine State had too many clouds for solar power to be effective.

But since early this year, Alex Glenn, the Duke Florida president, has touted one solar project after another, with promises of up to 500 megawatts over the next 10 years — more than twice the state's current solar capacity.

Last week, for instance, Duke announced plans for about 1 percent of its goal with 48,000 panels laid out in a Disney-themed design near Orlando. That followed a solar power event filled with great fanfare, including a set of Tesla electric cars, a week earlier at the University of South Florida St. Petersburg.

Duke isn't alone.

Florida Power & Light, the state's largest investor-owned utility, pledged in January to build three solar farms that would nearly double the state's current solar capacity. Gulf Power, the smallest of the investor-owned utilities, this year entered an agreement with the military for the state's largest solar power system so far.

So why have the Sunshine State's utilities suddenly changed their tune about solar?

Critics of the utilities say it's because they feel threatened by a ballot initiative that would essentially deregulate solar power in Florida through a constitutional amendment. Landlords could install solar panels on properties they own and sell that power directly to tenants, a practice that is currently illegal.

When asked at a Tampa Bay Regional Planning Council energy conference on Friday whether the ballot initiative is influencing the utilities' push for Solar, Glenn curtly responded: "No."

There are two reasons, he said: For one, panels have dropped in price by 60 percent, and second, battery storage systems are developing to allow energy storage when it is cloudy and at night.

"The most significant change is solar panels have come down," Glenn said.

Still, he said, natural gas-generated electricity remains cheaper than solar. But "four or five years from now, we think that's going to change" and solar will be even cheaper than natural gas.

Utility critics argue that the power companies have stymied solar's growth in Florida.

Florida ranks 15th in solar development, behind the likes of North Carolina and New Jersey. Georgia has been nipping at the Sunshine State's heels and has threatened to surpass Florida in solar development.

Meanwhile, the Solar Energy Industries Association ranks Florida third in potential for solar power generation.

Scott McIntyre, president of the Florida Alliance for Renewable Energy and CEO of Solar Energy Management, said solar panels have dropped substantially in price, but not just "in the last two or three months or the last six months."

"We would like them to participate and get behind the constitutional amendment," McIntyre said.

If the measure passes, solar proponents argue that it would open up Florida's solar energy market, which has largely stagnated for years. The measure would allow business or property owners to produce up to 2 megawatts of solar power and then sell that power directly to others, such as tenants, without having to go through a utility.

Under Florida law, only utilities can sell electricity directly to consumers, though solar proponents argue that 36 other states allow residents to sell it. By removing the utilities as middlemen, the argument goes, it could spur solar as a clean alternative.

The ballot initiative is currently before the state Supreme Court for review, and final approval of the language to place it on the 2016 ballot. The coalition will need an additional 600,000 signatures to get the petition on the ballot.

In a radio interview with WGCU public radio, state Sen. Jeff Brandes, R-St. Petersburg, described the ballot initiative as "game changing when it comes to solar."

"I'm not a fan of putting things in the Constitution like this," Brandes said. But "the people of Florida are rising up. Boy, what a wakeup call. I think it forces the conversation."

A large part of the success of the ballot initiative so far is that it enjoys broad support of an unlikely coalition that includes tea party and Christian Coalition conservatives and libertarians, as well as liberal environmentalists such as the Southern Alliance for Clean Energy, the Sierra Club and Greenpeace.

The coalition says the utilities have become fearful that they are losing their monopoly over the Sunshine State, so they're now reacting with plans for solar only to appease their customers.

"I think they're trying to do their best to try to stop the ballot initiative," said Tory Perfetti, director of the Floridians for Solar Choice, which is organizing the ballot initiative.

"They're going gung ho for this now," Perfetti said. "The fact that they realize that we the people have an alternative to the Legislature … I think all of a sudden they're trying to run for cover."

Debbie Dooley, a Georgia Tea Party leader who is helping with the ballot initiative, said if the utilities do support solar and the best interest of consumers, they should back the petition.

"They can't have it both ways, these utilities," Dooley said. "Duke Energy wants solar, but they don't want the consumers to have the choice of third-party sales.

"They're trying to say, 'We're not anti-solar, look at these solar projects,' " Dooley said.

Glenn and other utilities officials disagree with Dooley.

On the same radio show that Brandes appeared on this month, FPL executive Buck Martinez said his utility has been involved in solar since the 1980s. "We want to do solar in a manner that best meets the needs of our customers," Martinez said.

Glenn said in the analysis that he has seen, about 20 to 30 percent of rooftops are viable for solar in Florida. That means, he said, that while solar will play a significant role in the future, economics support more use of community-sized solar projects.

That supports the utilities' business model of centralized power, where they make their money from building power plants and selling electricity — something that rooftop solar and batteries in garages won't do.

But with the state becoming increasingly reliant on natural gas as its electricity generation source, Glenn said solar with its declining costs and battery storage can help it diversify.

"We think large scale needs to play a role," Glenn said. "You have to have your eggs in different baskets."

Contact Ivan Penn at ipenn@tampabay.com or (727) 892-2332. Follow @Consumers_Edge.