I assume there are some technical reasons why turbines are less practical, but could anyone explain what those are?
- costs 1): You would need a very different kite to have a turbine hanging in the air. Possibly rigid. They work with a flexible kite, that is possibly much closer to already existing high-performance kites/paragliding wings
- costs 2): You will need a much more expensive tether, as you now need to bring down the electricity that you've produced up in the air, while still being able to reliably and safely reel in your kite
- costs 3): Something happens in flight during testing, or maybe in production, and the kite comes crashing down. There goes your expensive turbine.
- power efficiency: Why would a turbine be necessarily be more power efficient? Action is reaction, so if you are going to remove a certain amount of energy from the air and your kite is stationary, you're going to have to produce a counter-force to stay in place. So how much of the potential energy are you actually using for power generation? Less than half, perhaps? So maybe the pump cycles of a dynamic kite are not that bad after all.
Just some thoughts.
Lifting things requires power, there is a formula for work done. Keeping things up does not require power, a chair does not collapse under you when it runs out of battery.
A ‘normal’ wind turbine generates a huge force on its foundations when it operates - that’s why they have to be so heavy. It’s not moving so no work is done.
That force does not care what is opposing it - whether it is fighting the strength of the tower holding up the turbine, or if it’s fighting gravity and a steel cable holding the kite. As long as the forces and their directions cancel out, it’s all the same.
Lastly, waste does not matter, wind power is available for many kilometres vertically.
If a kite is flying 500 meters above ground, it can suddenly access the power a turbine could not.
So if it accesses power that was inaccessible before, it’s a win even if half of it is wasted.
Lastly, none of this discussing has any relevance, only economics matters.
You care about cost of equipment, how long it lasts, how hard it is to repair, how many people are required to operate it and therefore salaries, where can you build it - a system could be 100% efficient but unprofitable.
> Lifting things requires power, there is a formula for work done. Keeping things up does not require power
When my helicopter is hovering it runs out of fuel. What is my pilot is doing wrong?