Indeed, in current wind power, the power take-off (PTO) axis would correspond to a small-diameter ball bearing.
But when the diameter of the rotor increases the generator rpm decreases while the linear speed remains low (corresponding to the diameter of the generator), leading to the implementation of a heavier generator. This is not a problem for wind power until the larger dimensions come, leading to Sway attempt for a larger annular generator which increases the linear speed. But weight is a crucial concern for flygen AWES.
We can consider Beaujean’ system as giant 1350 m diameter rotors whose power take-off is taken at the periphery. The designer was aware of the problem. If a central PTO shaft was designed like for current wind turbines, the generator would be far too slow and too heavy, resulting in a large and heavy gear.
The construction of a large annular generator can be too difficult. So I propose using large rings acting several small high speed generators.
If it is possible to set up a large ring by using a light construction, one can benefit from high speed generators (around 6000 rpm) with a density of several kW / kg, instead of a generator of 120 RPM which would be tens of times heavier to equal power. Let’s compare the Makani light generators at high rpm vs the generators of current wind turbines. And now high speed gas or airspace generators are proving to be sustainable.