Yoyo (of which the recovery phase is not taken into account here) or flygen crosswind kites generate an irregular power during the figure-eight or the loop. The cyclic variations of the tether angle cause it.
About 14’ after the beginning we can see the whole loop and hear the sound variations that occur periodically on Makani’s video during each loop:
Then during figure-eight we can also hear athe sound variations:
The irregular power of FlygenKite prevents to load a laptop or a cell phone, unless implementing a sophisticated and expensive regulator.
So for small crosswind devices an irregular power can be a problem.
For large devices like Makani the quality of the produced electricty could be lower (adding irregular wind power by itself), unless implementing expensive temporary storage, or using very smart grid.
Are there some deeper studies of this concern?