WASHINGTON — When experts on power grid reliability asked themselves recently how a cleaner energy future would look, seven of eight regional councils imagined how their systems would work with 10 percent wind power.
Only one, representing the southeastern United States, chose a radically different option: doubling nuclear power capacity.
Thirty years after the American nuclear industry abandoned scores of half-built plants because of soaring costs and operating problems like the Three Mile Island accident, skepticism persists over whether the technology is worth investing in.
Yet the pendulum may be swinging back. The 104 plants now running have sharply raised their output, emboldening utilities across the country to make a case for building new ones.
And the industry is about to get a big boost. In the next few days, the Energy Department plans to announce the first of $18.5 billion in loan guarantees for building new reactors.
The guarantees were authorized in a bill passed by Congress in 2005.
It has taken four years for the department to set up a system to evaluate applications and determine how much the borrowers will be charged for the guarantees to compensate the government for taking the risk.
Industry experts think the first guarantee will go to the Southern Company to build two units at its Vogtle nuclear plant near Augusta, Ga.
The money will flow amid a national credit squeeze and intense jockeying among the nation’s wind, solar, geothermal and nuclear sectors. Each is trying to cast itself as an ideal “clean” energy option as the nation moves toward reining in the carbon dioxide emissions linked to global warming.