[Obi_Juan_Kenobi]

> efficiency of 42% of Betz limit, which is inferior to standard utility-scale turbines

That isn't surprising at all; wind generation scales very very well with larger size. If it actually achieved 42% at that size, it would still be a major innovation.

But that's also a strong claim that requires very strong evidence. The reasons for inefficiency at smaller scales are fundamental: higher drag to lift. Essentially what they're doing is using the existing building as part of the device to direct wind. This is not a new idea, and in favorable conditions you can get some impressive numbers. But in real life..

https://www.renewableenergyworld.com/storage/small-wind-turb...