> 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 wit

> 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-turbines-driving-performance-52701/ https://www.renewableenergyworld.com/storage/small-wind-turb...