The Massachusetts Institute of Technology (MIT) and the Department of Energy's National Renewable Energy Laboratory (NREL) researchers have been studying a new way to implement offshore wind turbines – by floating them on platforms a hundred miles out to sea where wind gusts are strong and the turbines would be out of sight.
Today's offshore wind turbines usually stand on towers driven into the ocean floor but work only in water depths of about 15 meters or less. Paul D. Sclavounos, a professor of mechanical engineering and naval architecture who has spent decades designing and analyzing large floating structures for deep-sea oil and gas exploration, along with MIT colleagues and NREL's team, has developed an alternative. Their design calls for a tension leg platform (TLP), a system in which long steel cables, or ‘tethers,’ connect the corners of the platform to a concrete-block or other mooring system on the ocean floor. The platform and turbine are thus supported not by an expensive tower but by buoyancy.
According to their analyses, MIT says the floater-mounted turbines could work in water depths ranging from 30 to 200 meters. In the Northeast, for example, they could be 50 to 150 kilometers from shore. Encouraged by positive responses from wind, electric power and oil companies, Sclavounos hopes to install a half-scale prototype south of Cape Cod.