Vertical wind turbines a better option

Vertical axis wind turbines have the potential to solve some of the problems of generating energy from offshore breezes, U.S. researchers say. The economics of offshore wind power are different from land-based turbines due to installation and operational challenges, and VAWT architecture could transform offshore wind technology, scientists at the Department of Energy's Sandia National Laboratory reported. VAWTs offer three big advantages over horizontal windmill type turbines that could reduce the cost of wind energy, they said; a lower turbine center of gravity, reduced machine complexity and better scalability to very large sizes. A lower center of gravity means improved stability afloat and lower fatigue loads, and with the drive train on a VAWT at or near the surface, maintenance is potentially easier and less time consuming, researchers said. "VAWTs are elegant in terms of their mechanical simplicity," Josh Paquette, a principal investigator on the Sandia project, said. "They have fewer parts because they don't need a control system to point them toward the blowing wind to generate power." Sandia is conducting the research under a 2011 Department of Energy program to identify advanced rotor technologies for U.S. offshore wind power generation.