Flying Wind Farms

you can operate kites to do this. You need to stop the wind generator from blowing down wind = net zero perceived wind velocity. Ever ride in a hot air balloon. At 20 MPH ground speed you feel no relative wind at 1000 feet. Lower down you get ground turbulance and mixed winds as the wind on the ground is slowed by trees etc

something like a ship anchor can make the wind turbine stable. Wind tunnels are not really sharp like rivers so that makes a lot of distance. tou can get wind data from sodars or sound echo systems.

I doubt they would use a movable anchor. a tethered device with a pair of conductors to the ground for the power might get a lightning strike or two every day or two. A risky endeavour and it is probably not workable

you don't transport that energy to earth. perhaps good for using in space. something like filling fighter aircrafts in air. start war and other programs will find it OK and migrant birds fly from USSR to India on those wind channels easily.

I still think it will not be economic to use high altitude wind power. You must remember the max tether length is only a mile, maybe two for a tethered kite with wind generators attached due to mass of generators and alternate means to maintain altidute in zero wind co0nditions.

The jet stream is out of reach unless they get stronger tethers, although work in an orbital elevator has been talked about, we still need two orders of magnitude increase in strength to do that.

Some day a carbon or other strong stiff fiber might do this?

There is enough energy above and we really don't need much of it.

I really know how to use that wind power and this idea is not a joke. It is great fun and worth using it. Imagine traveling the entire world 100s of times without use of much fuel. Problem with wind tunnels is that they may make the crew up side down. Birds some how don't care for it and can come back into form from any angle. Best idea is to have a balloon shaped ship such that you have no idea of its tilting as long as inside stuff balances with respect to the gravity like water inside a balloon.

Learn from migratory birds.

Migrating birds fatten before the trip and can lose 40% or more of their bodyweight.

High flying sun powered planes with long glide ratios have been made, but they lose a lot of hieght in the dark. Balloons have been made that do the same, but high speed winds at high altitudes are more than they can combat to stay in one place. I expect that it is possible to make a sun powered very light plane with a great range ability. So far few have bothered to do it.

Back in 1975 NASA Dryden (at Edwards A.F.B.) worked on microwave transmission of power up to an electrically powered aircraft. I later saw the idea in Popular Science magazine excellently illustrated including interviews with Dale Reed, the project engineer. He also talked about exploring the idea of drone aircraft using the jet stream to generate and relay microwave energy to an earth station.