Wow, where to begin. First off, I'm really happy that Google continues to fund energy related start-ups, their solar and wind efforts are commendable.<p>Also, I'm fairly sure that the engineers behind this project are top notch and giving this project all they've got, it sure looks like they have picked some interesting challenges.<p>That said, I don't think this will ever 'fly' (pun intended) on any appreciable scale.<p>Wind is a fickle thing, and if you look at the design parameters of even the smallest windmills you realize that it takes bullet proof engineering to get a windmill to operate at all for any stretch of time without catastrophe, tying one to a kite seems to compound those problems to the point where even if the power generated were substantially higher than that on the ground you'd still be left with a higher per KW bill. Being able to operate in places where windmills are otherwise not viable is nice, but at 600 meters above the ground there will be substantial risk from getting kits entangled so the closest spacing will probably be such that a 'farm' of these will generate relatively little power for a given area of the planet over which the kites fly.<p>1 MW seems to be a pretty ambitious goal for a first setup, think about it, a 1 MW turbine sitting on the other side of a line will pull on the tether with a very impressive force, the kite will have to pull aloft a tether strong enough to withstand that force and up to 600 meters of power transmission cabling. These are not simple challenges. What I don't understand is why they don't build a 10 KW or so scale model and gain experience from that before going for a full MW, even a 10KW system flown for a year or two would give them plenty of experimental data to help design a larger one.<p>Then there are the liability issues, windmill towers are pretty solid and yet they've been known to fail. I figure the failure rate of kite lines+power lines would be substantially higher than that of a tower and so you'd have to contend with the occasional free flying kite+windmill combination.<p>All that said I wish these folks best of luck with what they're doing, but unlike the cheap solar panel revolution I highly doubt that this will ever be deployed at a scale large enough to be notable. Neat project though!