Offshore Wind Farms Could Cut Hurricane Winds

John Davis

jacobson1Not only do they generate lots of clean energy, but offshore wind farms could help lessen the winds of hurricanes. A new study from Stanford University researcher Mark Z. Jacobson, a professor of civil and environmental engineering at the school, says the data could give shore-based communities another reason to put in the turbines.

The researchers simulated three hurricanes: Sandy and Isaac, which struck New York and New Orleans, respectively, in 2012; and Katrina, which devastated New Orleans in 2005.

“We found that when wind turbines are present, they slow down the outer rotation winds of a hurricane,” Jacobson said. “This feeds back to decrease wave height, which reduces movement of air toward the center of the hurricane, increasing the central pressure, which in turn slows the winds of the entire hurricane and dissipates it faster.”

In the case of Katrina, Jacobson’s model revealed that an array of 78,000 wind turbines off the coast of New Orleans would have significantly weakened the hurricane well before it made landfall.

In the computer model, by the time Hurricane Katrina reached land, its simulated wind speeds had decreased by 36-44 meters per second (between 80 and 98 mph) and the storm surge had decreased by up to 79 percent.

While the researchers admit there is political resistance to putting in large wind turbine farms offshore, the incentive of saving a city billions in damages might give wind energy advocates another tool in their belt in the fight. For example, Hurricane Sandy in the fall of 2012 caused about $82 billion in damage across three states. Big arrays such as the ones proposed would cost between $10 billion and $40 billion per installation.