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Comment by searchhn | Hacker News Reader

This is cool ! How does it compare in size and power generation to a modern upgright wind turbine ?

Thanks! The size we're targeting now is a system of two kites on one tether, each with a wing span of 20 m and weighing 1650 kg. This would generate around 1 MW.

The largest off-shore wind turbines right now have 80 m blades and generate 8 MW at a weight of 1300 tonnes (excluding foundation), but the main reason they are so large is economies of scale, off-shore wind turbines are expensive.

Kite wind turbines do not have to be as large to be economical.

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.

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.

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