Nov 24 2009
Last year, the United States overtook Germany to become the largest producer of wind energy in the world. This capped a five year expansion of U.S. wind power during which capacity increased by about a third every year.
Robert Whittlesey and John Dabiri of the California Institute of Technology have developed a potentially more efficient wind farm design that maximizes the efficiency of land usage. They based their approach on the way that fish school, which they will present later this month at the 62nd Annual Meeting of the American Physical Society's (APS) Division of Fluid Dynamics will take place from November 22-24 at the Minneapolis Convention Center.
"When fish swim, they shed tiny vortices in their wake," says Dabiri. "By schooling together, they can potentially help each other swim by transferring energy between one another through these vortices."
Applying these same principles, Whittlesey and Dabiri have designed a wind farm of closely-spaced vertical-axis turbines (a design different from the more familiar propeller-type horizontal axis wind turbines). Their farm is arranged with the turbines closely spaced, so that as each is turned by the wind, it both extracts energy for itself and also helps to direct the flow of wind to the other turbines.
They made measurements of turbines designed by a Southern California energy company and fed the data into a computer model designed to optimally space the turbines. Their computations show that the power-per-acre of a wind farm could be increased a hundredfold. Next, the researchers will build a test field with real turbines and make actual energy production measurements.