The wind swooped along a narrow ridge of Backbone Mountain and coaxed the gigantic blades on dozens of sleek white turbines to turn in a graceful, choreographed routine, like birds pirouetting against the clouds.
The Mountaineer Wind Energy Center, which opened in December in West Virginia near the Maryland border, turns travelers' heads along winding, hilly Route 219 for good reason. Once limited largely to the Far West, electricity-generating windmills are beginning to sprout on hilltops and ridges across the nation.
Wind power developers are looking at the mountains of Western Maryland as the next frontier.
That region is ripe for development, they say, because it's windy, close enough to densely populated areas and offers plenty of available land on farms, mountaintops or coal mines, active and abandoned, in an area hungry for economic development
Developers say as many as 1,000 windmills towering more than 200 feet could someday dot Maryland's mountain ridges.
This year, Clipper Windpower Inc. and US WindForce LLC became the first two developers to win state approval to build wind energy centers with a combined 92 turbines in Allegany and Garrett counties.
The two companies have land deals in place and permits in hand to build windmill farms by the end of next year, though they still face significant hurdles.
Others hope to someday plant hundreds of wind turbines offshore in the Atlantic Ocean - including off Maryland's coast - in longer-term proposals that have stirred up far more controversy.
Improved turbines, a growing green-energy market and a federal tax credit are spurring development in the East, which has lower wind speeds than other areas of the country.
"Five years ago, the technology wasn't quite there. The cost of energy would have been too high," said Kevin Rackstraw, regional leader of eastern North America for Clipper, which plans to build up to 67 wind turbines on the Maryland side of Backbone Mountain near Oakland. The wind farm will generate 101 megawatts, enough to power 35,000 homes.
Higher energy costs and rising demand are creating a significant market for wind power, Rackstraw said, adding, "Wind is much more attractive than two or three years ago."
Officials with the state and Allegany and Garrett counties envision the first two Maryland wind projects as the start of something much bigger: a new industry for an economically lagging area of the state that has suffered more than its share of job losses.
Officials look to the wind farms to bring in construction and maintenance jobs, tax revenue and tourists.
The $110 million Clipper Windpower project is expected to be the largest single investment ever in Garrett County. It also would be the county's largest property taxpayer, generating more than $1 million annually. Project managers plan to pay $2 million to $3.5 million in construction wages.
"It's hard for us to say no to $100 million" in a single investment, Garrett County Commissioner Fred Holliday said during a community meeting last month near Cumberland.
"That's a lot of money for schools and roads and other purposes. People say, `My God, you're ruining the mountain.' But which is worse, houses or wind turbines? I think this is the way to go economically. This is going to help."
Wind power, which has been used for millennia, is the world's fastest-growing energy technology. It has burgeoned into a $10 billion-a-year industry, surpassing nuclear power in capacity installed each year, according to the U.S. Department of Energy.
Wind is free, nonpolluting and renewable, not imported and not subject to control by a cartel such as the Organization of the Petroleum Exporting Countries. And, because of the federal tax credit, the cost has come more into line with that of generators fueled by natural gas, at an average of 3 cents to 6 cents per kilowatt-hour. Coal-fired plants are generally the cheapest.
Still, wind produces a small fraction of the nation's power - about a third of a percentage point - enough for about 1.57 million U.S. homes.
The United States has about 17 percent of the installed wind capacity worldwide. Germany and Denmark are the leaders. In the mid-Atlantic region, only Pennsylvania, West Virginia and New York have wind power centers, most of which have begun operating since 1999.
Increasing wind energy, a goal of the federal government, remains challenging because, as any becalmed sailor knows, wind doesn't blow on demand. What's more, the technology costs more upfront than fossil-fuel generators do, and some prime wind sites are too remote from power customers.
Environmentalists have raised concerns over aesthetics, noise and the effects on migrating birds, which are sometimes killed when they fly into the rotors.