EF-3 Tornado snakes through a wind farm hitting just one turbine.

The blades are destroyed. The tower and the generator remain upright.

The rest of the units remain ready to be available to the grid as soon as the wind where they are drops below 49 miles an hour.

Other video I saw showed two turbines entirely surviving a less powerful tornado.

Bob is right to look into the source on this. Wind Watch gives us a bit of slight of information. The imaged event took place last year. By now, the extent of the damages should be clear, even the cost and speed of the repairs. That we are shown an “enhanced” video but not presented with that information raises enough of a question to suggest that Bob is correct in interpreting the video as more likely to be showing blade destruction rather than turbine destruction.

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When one googles “Wind Watch” here’s what turns up –

“National Wind Watch is a nonprofit coalition for raising awareness of the shortcomings of industrial wind energy and its negative impacts on the environment,”

Then if you go on to their site what you find is a lot of misinformation about industrial wind. “Industrial wind” is a recent friends of fossil fuels anti-renewable term.

You get BS like this “the giant turbines have not been shown to meaningfully reduce the use of other fuels on the electric grid “.

How stupid would have to be to not realize that if wind is producing electricity then some other generation source isn’t? Most likely dispatchable natural gas turbines.

BTW, people shouldn’t miss Thomas’s article on The Breakthrough Institute and their anti-renewable energy disinformation campaign.

http://cleantechnica.com/2013/06/17/the-breakthrough-institute-why-the-hot-air/#comment-932998769

There’s evil afoot….

The odds of an EF-5 hitting a wind farm are slight.

What’s encouraging to me is this gives us some indication how turbines/blades might stand up to large hurricanes. Hurricanes have much larger footprints.

Fortunately, locations where typical wind velocities are high enough to make attractive sites for wind farms are not highly correlated with locations at high risk for serious tornadoes.

One might also note that the path of even a high EF scale tornado probably would not take out a lot of the turbines in a large wind farm, so there would still be some power output to deal with. I’d be more concerned about hardening the transmission system.

I would think that the towers and turbines should be designed to resist a lot more wind than the blades.

http://www.aweo.org/windmodels.html

World’s largest blade –

“Remarkably, the 75-meter-long (246-ft) blades consist of a single component made from epoxy resin and balsa reinforced with glass fiber, cast in a gigantic mold using a process Siemens has cunningly named IntegralBlade.

Initially, three B75 blades will be put to use in a prototype 6-MW offshore turbine at Denmark’s national test center at Østerild. The sweep of the completed turbine will cover 18,600 sq m (200,200 sq ft) and the tips of the blades will move at 290 km/h (180 mph) at full lick. At a wind speed of 10 m/s (19.4 knots), the turbine will be hit by 200 tons (181 metric tonnes) of air every second.”

http://www.gizmag.com/worlds-largest-wind-turbine-blades/23578/

In the linked article in the piece it states that the taller tower turbine had blades installed when the tornado hit but the shorter tower turbine did not.

So we have one data point. I would have expected the blades to be ripped off with winds above 200 MPH. I figured that offshore wind farms that are hit by Category 5 hurricanes would need blade replacements. Perhaps not.

Despite taking a direct hit, two wind turbines at the Canadian Valley Technology Center (CVTC) stood intact after the storm passed. The turbines, on 85- and 126-foot towers–both fully constructed and used for educational purposes–did not suffer any visible damage.”

http://www.evwind.es/2013/06/06/wind-turbines-withstand-tornado-with-nearly-300-mph-winds/33454

Joshua boiled this down to a nutrient-less “A tornado that did little or no damage to two wind turbines located at the Canadian Valley Technology Center (CVTC).”