Germany’s GICON has completed one of the more remarkable wind-turbine construction projects in recent years. Its Schipkau prototype reached a hub height of 300 meters in September, putting the upper blade tip at a reported 365 meters. The lattice structure and telescoping inner tower allow the turbine assembly to be raised into place without a conventional crane lifting it to that extreme height. The engineering achievement is substantial, and the attraction of stronger winds higher above the ground is easy to understand.

But while GICON was developing its tower, conventional wind towers were getting taller too. Max Bögl recently erected a Vestas V172-7.2 MW with a 199-meter hub on a series-production hybrid tower. That changes the commercial comparison considerably. The generation advantage of reaching 300 meters looks impressive against a conventional tower at 100 or 150 meters. It becomes a different proposition when developers can already choose a hub approaching 200 meters.

I modeled two hypothetical wind farms using identical 7.2 MW turbines, rotor diameters and turbine counts, changing only their hub heights from 199 to 300 meters. Under the screening model’s wind assumptions, the taller farm produces 11.4% more electricity annually. That’s valuable additional output from the same generating equipment, although the gain varies considerably with the site’s vertical wind profile. Measurements at Schipkau suggest that some locations could do substantially better.

The construction question is less straightforward. GICON’s approach addresses some of the transport and lifting problems associated with very tall conventional towers, but a giant lattice structure has a different assembly burden.

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