With all the discussion around offshore oil drilling (following the recent accident in the Gulf of Mexico) I’ve had a renewed curiosity about the effects of wind turbines. People have proposed that we should limit the use of offshore drilling in favor of new energy technologies, and wind turbine farms have been proposed as a good alternative. Frankly, I agree. The risk profile of a wind turbine is insignificant compared to that of an offshore drilling platform.
However, given mankind’s propensity for shortsightedness, I’ve had to ask myself what we’re overlooking in the risk discussion. One long-term effect that I’ve wondered about is whether wind turbines would slow the wind. Clearly they operate by using the wind’s energy, which leads me to assume that the wind would be less energetic/powerful as a result. A quick search of the literature suggests that my assumption is right. Most of the wind turbine work I’ve come across is focused on the technology. But amongst this background noise I found an article Can large wind farms affect local meteorology? by S Baidya Roy, SW Pacala, & RL Walko of Princeton University.
Here is an excerpt from the abstract:
A wind turbine was approximated as a sink of energy and source of turbulence. The wind farm was created by assuming an array of such turbines. Results show that the wind farm significantly slows down the wind at the turbine hub-height level. Additionally, turbulence generated by rotors create eddies that can enhance vertical mixing of momentum, heat, and scalars, usually leading to a warming and drying of
the surface air and reduced surface sensible heat flux.
Does this imply that we shouldn’t use wind turbines? I don’t think so, but it does suggest that we need to keep thinking about what’s next. Wind power may be a great alternative to carbon-based power. But what will be the great successor to wind power? (stealing energy from other planets?) Clearly we can’t leverage the wind without some negative effects. Perhaps it’s an inherently lost battle, because anything that draws power is going to have a systematic effect. But that shouldn’t stop us from working toward a solution.
