A growing number of scientists and engineers are betting that a huge part of America's struggle with greenhouse gases and dependence on foreign oil can be partly solved by returning to one of the first energy sources tapped by humans -- wind.
Harnessing the wind could produce enormous amounts of clean energy, but even this seemingly benign resource is not without its problems.
Environmentalists who at first embraced the idea of dotting the land ape with windmills have cooled to the concept because they can be deadly to birds, and, to put it bluntly, they can be pretty ugly.
Suitable land is also scarce and frequently needed for other purposes, so development of wind farms in this country has lagged behind some other areas of the world. Wind power set a new record in Europe last year, growing by 23 percent, and it is second only to gas-fired generators in new capacity.
But in Europe, as well as other parts of the world, developers are increasingly moving offshore with their wind turbines, erecting them on huge platforms in relatively shallow water where the winds are more reliable than on land.
That's not happening in this country. At least not until now. But there is evidence that is about to change, and change dramatically.
Several proposed projects are moving toward approval for sites off the mid-Atlantic shore, from the Carolinas to New England, aided by a new study that has put some numbers on the energy potential of that coastal region.
"The numbers are amazing," says Willett Kempton, professor of marine policy at the University of Delaware, who led the study. "We didn't expect them to be that big, for sure."
Offshore wind turbines could produce enough electricity to power nine states, plus the District of Columbia, with a surplus of 50 percent for future growth, according to the study. At the same time, carbon dioxide emissions would be reduced by 68 percent, and all greenhouse gases would be reduced by 57 percent, according to the study, published in the Jan. 24 issue of Geophysical Research Letters.
But to reach those numbers, the scale of the project would have to be equally huge. The numbers are based on 166,720 wind turbines, scattered over more than 50,000 square miles from Cape Cod to Cape Hatteras.
Most would be visible from shore, and intrusion into coastal waters by any type of industrial activity is a hot-button issue in many quarters. But Kempton, along with fellow researchers at Stanford and the University of Delaware, is convinced it not only can be done, but will be done, at least in part.
"I'm almost certain it will happen," he says. "We have a proposal off Cape Cod, another proposal off New York, one off Delaware, [and] New Jersey has said they're going to do it. Maybe one of those will get blocked, but even Cape Cod has passed every review, every regulatory hurdle it's faced."
That's significant, he says, because a well-financed opposition group has fought in several arenas to block the wind turbine project.
Kempton's group has completed surveys in two communities to sample public opinion, and found very different sentiments. In Cape Cod, he says, they found "a statistically significant majority that were opposed." In plain English, most people hated the idea.
But in Delaware, he says, they got "amazingly different results."
The researchers say they are puzzled by that difference, but it's likely because of a subtle difference in the two surveys. One question was asked in Delaware, but not in Cape Cod. It went something like this:
"Would you rather develop offshore wind, or would you prefer to continue to develop more power plants that run on coal and natural gas?"
That may be partly why only 5 percent of the people surveyed in Delaware said they would prefer more coal and gas production, and 95 percent said they would rather have offshore wind. That is, of course, the fundamental question concerning any form of energy. It's always a tradeoff. And wind is like all other sources of energy -- you tap into it where you find it, not where you would like for it to be.
But is the proposal to develop the mid-Atlantic area technologically feasible? The researchers say they were guided by one fundamental principle: No breakthroughs are needed.
"We're not assuming any new technology," Kempton says. "We didn't assume anything that's not already been done and is in the water and generating electricity."
None of those examples are in this country, however. Denmark is the world leader in offshore wind farms, but other countries, including Scotland, are jumping in.
Not all areas are suitable for offshore wind farms. The Delaware researchers excluded large areas because they were in migratory bird flyways, or heavily traveled shipping lanes, or too close to popular beach resorts.
And much of the Pacific coast is too steep for offshore towers, although that may change as well.
Paul D. Sclavounos, a professor of mechanical engineering and naval architecture at MIT, has designed a floating platform that could be anchored 100 miles offshore, where it would be invisible from land. Sclavounos, who has spent decades designing large floating structures for deep-sea oil and gas exploration, is hoping to try out his idea in a smaller model off the coast of Cape Cod.
"We'd have a little unit sitting out there and could show that this thing can float and behave the way we're saying it will," he says.
Kempton and his group did not include floating platforms in their study because they have yet to be proved. But is it really practical to think in terms of 166,720 offshore wind turbines? That's a lot of stuff.
Richard Garvine, Kempton's colleague at the University of Delaware, points out that the United States has muscled its way past big hurdles in the past. He notes that in the military buildup prior to World War II, the U.S. produced 2,000 warplanes in 1939. By 1946, the U.S. had put 257,000 aircraft into service.
"We did that in seven years, using 1940s technology," Garvine says.
So a few wind farms? A piece of cake, technologically speaking.