March 12, 2014 | 3
According to Stanford Professor Mark Jacobson, offshore wind turbines could reduce onshore damage from hurricanes without sustaining significant damage themselves. According to his new study, published in the 26 February issue of Nature Climate Change, large arrays of offshore turbines can reduce wind speeds by up to 50% and storm surges by 6-79%. As a result, cities upstream of the wind turbines could sustain much less damage.
In this project, Jacobson’s group numerically modelled the atmosphere and ran simulations for Hurricanes Sandy, Katrina, and Ivan. In all cases, the presence of large offshore wind turbine arrays reduced the wind speeds of the incoming hurricane. Furthermore, the hurricanes themselves dissipated much more quickly once they hit land than when the turbines were removed from the simulations.
Taking a step back, this result broadly makes sense. Thermodynamics tells us that energy is not created or destroyed – rather, it changes form. In this case, a portion of the energy in the wind is being transformed into mechanical energy (the turning of the wind turbine’s blades) and then electricity.
For those who might wonder about the hurricane’s impact on the turbine itself – the study also found that the hurricane’s wind speeds dissipated too quickly to cause significant risk to the turbine. In fact, even in the case of Hurricane Katrina in the Gulf of Mexico, the group observed that wind speeds remained below critical levels.