Good one.
But seriously—big 3/4-spherical volume, inlet offset on the upwind side creates an internal tornado, exit at the center top into a swivel connection that always points downwind. Exhaust into a high-bypass venturi that creates a powerful suction on the air inside. Extract energy but whatever means necessary.
Bucky Fuller pitched indoor windmills for the ease of maintenance.
Since I last posted I'm wondering about a big chamber below high tide level (somewhere there's 10-20ft tides) with an air opening above low tide level, With every change of the tides, it would be a positive displacement air pump. So I'm wondering if a big chamber could recharge a smaller chamber to a higher pressure, 'cause that's recursive and scalable.
Compressed air car, here i come. Powered by the Moon!