Called Babcock Ranch, the city will aim to build 19,500 houses and about 6 million square feet of retail, light industrial, and office space when it is completed, the developers said.
The entire project is expected to cost $2 billion.
Syd Kitson, chief executive of Kitson & Partners, said Babcock, which will help create 20,000 jobs, can serve as a model for other communities throughout the nation.
"Babcock Ranch will be a living laboratory for companies, workers and families ready to reap the rewards of innovation," Kitson said at a press conference introducing the project.
A spokesman for the project said it will be the first solar-powered city because it will use only solar power during the day and produce more solar power than it needs and so will be a net exporter of solar power.
In addition to having its electricity generated from solar energy, the entire city is expected to have wireless Internet access and electric-car chargers.
Construction of the city center is scheduled to begin in June 2010, with the first residential and commercial buildings targeted for late 2010.
With the United States reeling from recession and falling housing prices, U.S. President Barack Obama has pledged to create millions of jobs by moving the country toward a green-energy economy.
Florida, in particular, has suffered from the housing bust. The state is now staggering under high mortgage foreclosure rates, dropping home prices and slowing population growth.
Obama wants 10 percent of U.S. electricity generated by renewable sources such as wind and solar power by 2012 and 25 percent by 2025. The stimulus package Obama signed into law earlier this year included billions of dollars for clean energy investments.
The utility and realty developers said they were not planning on using stimulus money for the projects at this point.
Groundbreaking for the $350 million to $400 million plant will begin late this year subject to state regulatory approvals, Eric Silagy, chief development officer for Florida Power & Light, said at the conference.
Silagy said the state government of Florida has been extremely supportive of renewable energy and he was optimistic about winning approval for this new plant.
"We have three projects that are under construction and I think that's evidence that they are very committed to this," Silagy said. "With that continued commitment we'll be able to move forward with project very quickly."
Florida Power and Light said the construction of its plant will not be dictated by the status of the planned city.