Too much wind not good for windmills

Winds are gusting to 30 miles an hour as a cold front replaces Iowa’s unseasonably warm weather. Sometimes you can have too much wind, even if you’re running a windfarm like Steve Dryden, head of Midwest Renewable Energy. Optimum windspeed for the maximum electrical generation is about 35 miles per hour, and when wind reaches 56 miles an hour, he says the turbines are shut down so their turbine generators aren’t over-stressed. Eighty-nine giant turbines spin atop 235-foot towers in Worth County but Dryden explains they shouldn’t spin too fast. The tips of the fins have airbrake switches that flip open at a certain speed, slowing them and when they get to a reduced speed, brakes around the shaft in the generator lock, like the hand brake on your car. While there’s a maintenance crew with a shop at the Top of Iowa Windfarm for minor repairs, a system of computers will automatically handle the shutdown if winds get too gusty. A computer sees the windspeeds and automatically shuts them down at a certain speed, mainly because they’d overheat the generator. Dryden says with a buyer signed up for the electricity from a second windfarm, they may begin construction of another array of the turbines on the east wide of Interstate 80 by spring.