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'Windmill': China tests world’s first megawatt-level airship to capture high winds
(interestingengineering.com)
This is a most excellent place for technology news and articles.
Wouldn't the heavy transmission line itself act as the anchor like the chain on a cruise ship?
You are aware that a ship lays several times the depth in chain on the ground as weight. And the chain is much heavier as the tether will be, or it would not really get up high. And the distance between ship and ground is rather fixed, while the windmill blimp is in a rather floating position.
No, I think a bunch of heavy duty ground anchoring is necessary here.
On the other hand, as the Chinese are rather good at planning important things like that, I could imagine them to set up some anchor points ahead: Bury a large lump of concrete somewhere in the city. Maybe use it as an open place in a park, where nobody would notice that instead of a layer of stones it is actually going a few meters deep. Have a metal trapdor in the center where you can hook up a blimp to a connection below, and have a way to plug the power into the local grid. If catastrophy happens, drop off the blimp, blow it up and send it skywards. The park should give more than enough space to set it up.