Here's one of the more awe inspiring developments in renewable energy that I've seen - Super Kites for harnessing wind energy:
Its exciting because this is a totally new way of thinking about wind energy production. It even seems a bit science fiction. If successful in scaling and achieving performance, it would present a real paradigm shift.
In many ways this reminds me of the shift from sails into steam engines for propelling ships (a case in which the further addition of sales did not provide sufficient power gains). Ironically, here the shift is moving in the opposite direction: Back from a rotating blade design and into a sail / wing design.
But back to reality... Achieving such solution will take many years, and significant funding to get to commercial scale.
As with many of the early stage, disruptive innovations in the energy space, this is a good example of the many hurdles a project must overcome, as it moves from the drawing board, to a pilot system, and through to a commercial grade system. These include proving the technology works, its performance, the full system reliability (across various conditions and time periods), the lifetime system costs (including ongoing operations and maintenance which seem high in this case), etc... Even once all these are achieved, there is still the challenge of finding appropriate locations, permitting, accessing grid transmission (a huge problem, which I'll try to touch on separately), air space permits (beware low flying planes), and so on.
Not an easy task - but if you're going to change a paradigm - I guess that's what it takes.
And there's one great thing in going after the wind energy space - The potential is so great that there's room for any successful and economic solution.