[jo909]

But with a traditional wind turbine with 80 meter long blades, the total "footprint" for each one is roughly a 160 meter wide circle. In principle you don't need much space between those circles in a bigger wind farm (but because of turbulence and the wind shadow there usually is).

What is your "wind farm" model? Reserving a kilometer wide circle for each kite pair does not really seem feasible even off-shore.

[Grustaf]

The wind shadow from a traditional wind turbine is actually very significant. For example, at the London Array, a very modern wind farm, they have 175 wind 3.6 MW rated turbines over 90 square kilometres, so about two per square kilometre.

Some scholars believe that kite energy can best this by a wide margin. For example, you can put the kite systems at alternating heights to combat the problem with wind shadow, and there is no reason why you wouldn't be able to have a significant overlap in the circles, since the wind will be blowing in close to the same direction throughout the wind farm.