THE WEATHER CHANNEL reminds me of my Oklahoma years and the ecstatic weather presenters who would gloriously point to Doppler radar pictures of impending microburst activity. Some of America's best Doppler radar observers live in Oklahoma, home of several massive wind power towers towering more than 200 feet high (not the low profile freeway turbines at left). When the wind turbine blades spin rapidly, their vortices produce the same radar effect of sudden downdrafts, leading to red spots on the weather radar that might appear to be significant thunderstorm activity. In the heart of Tornado Alley, new installations come with a health warning for untested weather radar observers. During high-stress periods just before the arrival of snowballs called "hail", some meteorologists might react to red blotches next to wind farms as deepening mircoburst activity. Wind farms built within 11 miles of Doppler radar sites can confuse the special tornado radar arrays. And while the weather detection technology improves, the interim solution may be to stop and park blade rotation. That's not always the least stressful tactic for a 20m blade so I'm interested in technology that lets big blades freewheel below a vortex-generating speed. Sent mail2blog using Nokia E90 Boingo-powered Barnes & Noble wifi service in Lancaster, PA 17601.
