The Finch Formerly Known As Gold

16 November 2004

We may as well try and catch the wind

Mike at Okiedoke turns up a tale of turbines and what they can do, and the models suggest that the more we have, the greater the impact on the weather:

For the study, a [virtual] wind farm consisting of an array of 10,000 turbines with rotor blades 50 metres long was set up in a 97 x 97 kilometre area in north-central Oklahoma.

During the course of the experiment, the turbines were seen to trap a cool nocturnal jet of air, present in the Great Plains in Oklahoma, that separated the cool moist air near the ground from the drier, warmer air above.

The bottom line:

During the day, the model suggests that wind farms have very little effect on the climate because the warmth of the sun mixes the lower layers of the atmosphere. But at night, when the atmosphere is stiller, the wind turbines have a significant effect.

At 3 am the average wind speed in Oklahoma is 3.5 metres per second, but it increased to around 5 m/s in the model wind farm. The model also suggested that the temperature would increase by around 2°C underneath the 10,000 turbines. Over the course of a day this averages out to an increase in ground-level wind speed of around 0.6 m/s and a rise in temperature of around 0.7°C.

And without so much as a single extra molecule of carbon dioxide. Imagine that.

Of course, there ain't no such thing as a free lunch, and some of us are already buying the output from wind turbines. Still: 10,000 of them? OG&E's commercial facility is using a total of thirty-four, and they're smaller than the ones described in the experiment: 34-metre blades, rather than 50. I'm inclined to think we're going to have to see some serious conversions en masse to wind power before we start to see major atmospheric disturbances.

Then again, every air mass in the world passes over Oklahoma, or so it seems; the cumulative effect might be greater somewhere farther away. Further studies will obviously be needed.

Posted at 9:25 PM to Family Joules , TANSTAAFL