We all know wind turbines can produce electricity, but have you seen them produce lightning?
When scientists trained high-speed cameras on a wind farm in Spain, they captured lightning bolts shooting out of the wind turbines. Tall structures like towers can initiate ground-to-cloud lightning, but ever-spinning wind turbines present a unique challenge.
Under certain cloud conditions, the scientists observed electrical discharges every three seconds that matched the spinning of the turbine blades. Occasionally, the discharges turned into a full-on lightning flash. Fast-moving rockets can be used to artificially initiate lightning, and rotating turbine blades work the same way.
Spinning high in the air, wind turbines have always been vulnerable to lightning damage. A whole wind field in Germany was taken out this way. While the industry is used to studying how lightning affects wind turbines, the study's authors end with a reverse question: Are wind turbines affecting how often lightning strikes in the region?
That raises another question in my mind, however impractical. Watching lightning flash around turbines—machines designed to harness energy of another kind—I found myself wondering if the dream of lightning farms could still be alive, after all. [Journal of Geophysical Research: Atmospheres]
Lead image from video via Montanya et al, Journal of Geophysical Research: Atmospheres