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World’s first megawatt-level airborne 'windmill' feeds power to grid
(interestingengineering.com)
Everything about energy production and storage.
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Interesting but i have a number of serious doubts about this ever becoming a viable technology. Foremost of which is what happens if the helium container bursts? It would result in a massive building-size object crashing to the ground anywhere within a 6500 foot radius of the ground tether point.