MIT designs 'invisible,' floating wind turbines

Paul D. Sclavounos, a professor of mechanical engineering and naval architecture, worked with the National Renewable Energy Laboratory (NREL) to design a system that uses cables to tether large turbines to floating platforms.

The tethers connect the platform to concrete blocks on the ocean floor in up to about 650 feet of water. According to Sclavounos and the NREL, the arrangement is stable enough to operate even in large waves brought by a hurricane because the design limits the turbine to mainly back-and-forth movements, rather than up and down.

Wind power is one of the fastest-growing clean-energy sectors worldwide, but proposals to build offshore wind turbines have met public resistance in the United States, largely due to aesthetic concerns.

Traditional offshore turbines are placed in relatively shallow water and visible from the shoreline. One notable example is the Cape Wind proposal--a 420-megawatt facility that has drawn opposition.

Encouraged by positive responses from wind, electric power and oil companies, Sclavounos--who previously worked building offshore platforms for deep-sea oil and gas exploration--hopes to install a half-scale prototype south of Cape Cod.

In a statement, he said that the 90-meter-high systems would generate twice as much electricity per installed megawatt as near-shore turbines because the winds are strong and steady farther out at sea.

Construction of the turbines, which would be large, multi-megawatt systems, would most likely take place onshore at a shipyard. They could conceivably be towed to different locations, according to MIT and the NREL.