I have to say I am impressed by this news of the first flying wind farm. It is at a prototype stage but it is the very idea that is amazing me.
Rather than having those gigantic wind farms built on ground why can we get a similar result by setting them hovering in the sky? I would have never dreamt of such a solution because at first glance it makes little sense. Sure, there is plenty of wind some hundred metres above ground (slightly more, actually, that at ground level!) but it would take power to keep this infrastructure hovering so in the end the balance will be negative, or so I assumed.
It turns out that is not the case. A few years ago a “moonshot” company, Makani, came up with the idea of using a wind power generator on a kite, tethered to ground, to produce power at low cost. They developed a prototype but in the end the idea proved impossible to turn into a viable -affordable- product. They released their ideas, patents and experience in open source for others to continue.
Now Kitekraft, a German start up, has completed its maiden flight for their wind power generator installed on a “drone” kite. Technology, in these last few years, has progressed enormously in the drone domain and this is what is enabling Kitekraft solution. The drone is raising the structure to an appropriate position and then the structure morphs into a kite that is self sustaining in the wind. At the same time the wind spins the wind blades of the turbines (see first photo) and the electricity is harvested through the tethering cable.le
By merging drone and kite technologies Kitekraft feels they can deliver an effective product that can operate in areas where wind farms are not feasible (for technical /economical / societal hurdles).
A case in point would be providing power in small islands where the space available is limited (think of Maldives atolls). The kite structure is much less intrusive than a wind power generator, it is smaller and stays up in the sky, almost un-noticeable. The expected power output is lower than today’s wind turbine, they expect to deliver some 100 kW per kite. Not very much but quite adequate for small places.
The energy budget is ok, since you have to use power to lift the structure, but that takes very little time, and then it hovers like a kite being self-sustained by the wind. It is tethered and so it can be (automatically) controlled from ground at very low cost. Again, in a use scenario like powering a small island community, the kite can hover over the sea some hundred meters from the shore.
It is not a product yet, Kitekraft is planning for a serie of test in the coming months and the are confident to be able to deliver commercially in 2022.