Even some energy-conscious Massachusetts residents oppose a plan to put dozens of electricity-generating wind turbines on towers about eight kilometers off the southern coast of Cape Cod, saying they would be an eyesore. But huge turbines in development at General Electric could make battles with coastal residents a thing of the past. Researchers say the turbines could be placed on floating platforms, far at sea and invisible from the shore.

In March, GE announced a $27 million partnership with the U.S. Department of Energy to develop 5- to 7-megawatt turbines by 2009, supplanting the company's current 3.6-megawatt turbines. Each of these giant energy factories, with rotors 140 meters in diameter, would produce enough electricity to power up to 1,750 homes -- and at a more economical rate than smaller turbines, since the cost of building offshore wind farms depends more on the number of turbines than on their size.