Published on February 28th, 2014 | by James Ayre8
Offshore Wind Farms Hold Potential To Weaken Hurricanes, Research Finds
February 28th, 2014 by James Ayre
Large offshore wind farms — ones possessing thousands of wind turbines — hold the potential to notably diminish the power of large hurricanes, according to new research from Stanford University and the University of Delaware.
In particular, the research found that such wind farms could have limited the power of three recent real-life hurricanes (Sandy, Isaac, and Katrina), both decreasing their wind speeds and limiting the accompanying storm surge. These are factors which would have greatly lessened the billions of dollars in damages that the storms all caused.
The findings were the result of computer simulations by Professor Mark Z. Jacobson, a professor of civil and environmental engineering at Stanford — one who has spent the last 24 years using computer modeling to study climate, weather, air pollution, and energy. Recently, his work has turned to the simulation of hurricane development, and also to the investigation of wind turbine energy extraction potential.
This new work bridges those two subjects — what would happen if a hurricane encountered a large array of offshore wind turbines? That question entered Jacobson’s mind while performing earlier research, and led to this new research. Would the energy extraction due to the storm spinning the turbines’ blades slow the winds and diminish the hurricane, or would the hurricane destroy the turbines?
What he found was that wind turbines “could disrupt a hurricane enough to reduce peak wind speeds by up to 92 mph and decrease storm surge by up to 79%.”
“We found that when wind turbines are present, they slow down the outer rotation winds of a hurricane,” Jacobson explained. “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.”
Stanford University provides more info:
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%. For Hurricane Sandy, the model projected a wind speed reduction by 35-39 meters per second (between 78 and 87 mph) and as much as 34% decrease in storm surge.
Jacobson acknowledges that, in the United States, there has been political resistance to installing a few hundred offshore wind turbines, let alone tens of thousands. But he thinks there are two financial incentives that could motivate such a change.
Those two financial incentives are, of course, the reduction of hurricane damage costs (Hurricane Sandy caused $82 billion in damages), and the simple fact that wind farms pay for themselves in the long-term — especially when you factor in the health and climate-related costs of fossil fuel power.
“The turbines will also reduce damage if a hurricane comes through,” Jacobson stated. “These factors, each on their own, reduce the cost to society of offshore turbines and should be sufficient to motivate their development.”