The turbine is designed to be free yawing - such as described in this paper: https://backend.orbit.dtu.dk/ws/portalfiles/portal/5134230/Yaw+stability.pdf
It might be used in other commercial turbines, but the only one I know of is the Gaia 133
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I like the Kite-X design.
Certain aspects of it are compelling.
I do not agree though, with what was said at the beginning of their interview, that their small turbine’s mass-to-power ration can be compared to MegaWatt turbines. We all know about the cube/square laws of scaling. Pretty much ALL small wind turbines make a lot more power per unit weight than larger ones, just as a radio-controlled stunt plane can always outperform a full-scale airplane.
I don’t think the Kite-X turbine has a better power-to-weight ratio than other small turbines, assuming they are high-quality one, which has become rare with the advent of imported junk on Ebay.
The guys interviewing, however, I view as a bad source of information.
These guys will believe anything.
They do not seem to have the technical acumen to realistically analyze the technologies they purport to review.
Remember this interview with Harmony Wind Turbines?
Harmony Turbines | The Perfect Small Scale Wind Turbine? (youtube.com)
How about their enthusiasm over “Aptera” - the car that is forever in development, but never ready?
Aptera Motors: A Paradigm shift in EV technology (youtube.com)
Can Aptera Compete With Tesla?? | Disruptive Investing News (youtube.com)
At about 4:00, KiteX is given for 16 W/ kg, in contrast to 2 W/kg for a large wind turbine.
Part of the difference can actually be attributed to “the cube/square laws of scaling”.
But this is not enough to explain the low mass of KiteX which is due (and this is well explained in the interview) to its structure which is similar to that of some AWES.
Indeed, if I am correct, almost all tension forces are absorbed by a sort of TRPT, which allows to relieve the rigid parts and makes them lighter.
I didn’t rewatch it, but I also agree that it’s not fair to compare specific power without taking into account the scaling laws. (If you want to compare the technology). I think it’s just my co-founder Christoffer way of trying to explain that our turbine is very light in simple terms.
I’m still quite certain that if you had an equally well engineered version of our turbine and a conventional design at a similar size below 100 kW that the tether supported would come out significantly lighter.
Not that we really care about lightness in any case. Mostly we care about cost 
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Actually, I’d say the Kite-X turbine delivers LESS peak power per unit mass than most small turbines, but again, that comparison is not that meaningful anyway, since the Kite-X turbine is designed for max total energy capture in light winds, whereas most small turbines are simpler, but designed for areas with strong winds.
Of course, a turbine designed for light winds will not deliver the same power per unit mass as a turbine designed for a strong wind resource, as most are.
To me, that is what sets Kite-X apart from most other small turbines - good performance in light winds, which most hope to have, but few do, especially at a typical campsite. Nobody wants their tent to blow away!.
I will point out though, that with the added gearing (gears? belt drive?) the complexity and failure points are increased. It might work better to use a larger direct-drive alternator, or one designed for lower RPM, than adding all that weight and complexity. Belt drives for wind turbines is a typical newbie idea that has never gone mainstream, as far as I know. I tried a chain drive years ago, against the advice of wind energy veterans, and found out everything they said was true: more noise, and I don’t remember exactly what went wrong - rust? Whatever it was, I never used a chain drive again.
Anyway, as cool as it is, It does not seem like a very robust design overall, and to me, it looks like it might get ripped apart in a very strong wind.
Also I seem to remember a customer talking about buying new blades - this implies that the blades are not robust, since a turbine designed for occasional use camping etc., should not be getting enough wear to need new blades, and any turbine that has only been around for a few years should not need new blades yet anyway.
Still, it’s a pretty nice effort - at least it works and can be useful for something!
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Yesterday we set a new production record with our Tethered Wind Turbine: 80 kWh in a single day — from 330 kg of turbine
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What I like most isn’t the number, it’s the shape of the day. Steady output hour after hour through changing wind — at its working point from ~6.5 m/s and up, with the drivetrain fully used rather than chasing peaks. Same average wind as our previous record in June, lower gusts, and a lower peak power — yet 7% more energy. That came from simulator work, control optimization and load analysis, not from a windier day.
Simulator, control laws, fatigue and ultimate loads, and material data are now tentatively in place, with a 20-year fatigue assessment behind every primary structural member.
Next step towards IEC 61400-2 is the duration test — 6 months of operation and 2,500+ hours of production — which we plan to start in about 4 weeks.
Excited about how far we have come, and looking forward to delivering the TWT-11 to our eager customers!
Go team KiteX!
This work is supported by EUDP - Det Energiteknologiske Udviklings- og Demonstrationsprogram, and we run it alongside DTU Wind and Energy Systems, who host the turbine at Risø. Thanks for the site and the sparring on the HAWC2 model.
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Nice to hear about this. 