There’s a tornado but the turbine is still moving so slow? You’d think they would be capitalizing on all that free wind!!
Those blades are way, way, way bigger than you think they are. They are moving extremely fast even at normal speeds. That 15ish rpm converts to around 1.5 rads/s. Modern windmill blades are something like 70m long – so we’re talking speeds of 100m/s or north of 350 kph / 220 mph.
Pretty comparable speeds to the windspeeds of the tornadoes in question during routine operation. Of course, there’s a lot more intensity with a tornado, but windmills are actually designed to let most of the air pass them unimpeded because it makes them work more efficiently.
Of course, their energy production will be deliberately curtailed under high winds because the generators and infrastructure hooking them up can only handle so much – they’ll brake the blades, or rely on back-emf from the motors, or some combination of those factors to prevent them from over-generating.
Of course, unlike typical wind being harvested by the windmills, the tornado’s airflow is far from laminar, meaning that even with their highest intensity, they will be losing a lot of efficiency in driving those blades.
…the tornado, of course, will simply knock them down.
Thank you for the detailed answer. I was really just making a joke, but I still do appreciate how much I have learned here.
Usually in a tornado you have a lot of debris flying around. The faster the blades go, the higher the probability to hit debris and damage the expensive blades.
I saw only one go down.
There is other footage which shows more going down; scroll down for the lower video.
Turbines are now built to withstand events like tornadoes, hurricanes and typhoons because of advances in technology since the early designs of the 1990s. They have built-in mechanisms to lock and feather the blades, changing their angles, when winds reach 55 miles per hour. That reduces the surface area of the blades pointed toward the wind.
“You will lose a blade here or a blade there,” during windstorms, Mr. McLachlan said. But a complete knockout is unusual, he said.
I don’t think I’ve seen anything like this since a hurricane took out a whole wind farm in Hawaii in the 1990s. Quite frankly, the loss of homes and lives is a much bigger deal.
