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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.
What matters is scalability and how much material and cost you need to produce per energy unit. Kites (either parasails or fixed wing) are much simpler, can be scaled up too, and you only need a simple cable that pulls the generator's winch. Overall kites seem much more efficient to scale up.