Comment on 'Windmill': China tests world’s first megawatt-level airship to capture high winds

AceBonobo@lemmy.world ⁨5⁩ ⁨days⁩ ago

• Kushan@lemmy.world ⁨5⁩ ⁨days⁩ ago

  The article says:

  The S1500 features a main airfoil and an annular wing that together form a giant duct. Inside this duct are 12 turbine-generator sets, each rated at 100 kW.

  That suggests to me (admittedly a layman) that each blimp is more like 1.2MW?

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  • Railcar8095@lemmy.world ⁨5⁩ ⁨days⁩ ago

    The title itself already says it’s 1MW.

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  • AceBonobo@lemmy.world ⁨4⁩ ⁨days⁩ ago

    Sorry about that, I got all excited at just a tenth of what they are trying to achieve. Oops

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    • Kushan@lemmy.world ⁨4⁩ ⁨days⁩ ago

      It’s all good mate, we’ve all got over excited at times.

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• Cocodapuf@lemmy.world ⁨4⁩ ⁨days⁩ ago

  Would it be possible to use heat to get it to float, instead of helium? Heat it up with electricity.

  Sure, that would be possible. The generators themselves will produce a fair amount of heat. It’s also going to have a fair amount of passive lift, as it’s essentially a kite. So simply being able to maintain a rigid shape and airfoil will do a lot to produce the desired lift.

  I have to wonder though, how much the power transmission lines weigh, that seems like a serious limiting factor on maximum attainable altitude.

  The transmission line question is interesting though, there’s a complex optimization calculation there. Traditionally with wind, larger turbines are more efficient. As you increase the turbine blade size, the area that the blades cover (and thus power generation potential) increases more than the mass of the blades do. So the result is (generally speaking) a larger wind turbine is more efficient than a smaller one. But now factor in the transmission line… The larger the turbine the more power it generates AND the thicker (and heavier) the transmission line has to be for its entire length. To complicate things more, higher altitudes mean stronger and more reliable wind. So now how do you optimize for turbine size/cable gauge, and cable length/altitude?

  It seems tricky, but like perhaps there’s just a right answer, an optimal size.

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  • frezik@lemmy.blahaj.zone ⁨4⁩ ⁨days⁩ ago

    Can they preference the generation to favor voltage over current? Current is what tends to need really thick cables.

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• humanspiral@lemmy.ca ⁨4⁩ ⁨days⁩ ago

  it is 1.2mw = 12x100kw

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  • AceBonobo@lemmy.world ⁨4⁩ ⁨days⁩ ago

    Did they actually generate power during the teat flight?

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    • humanspiral@lemmy.ca ⁨4⁩ ⁨days⁩ ago

      “demonstrated 1mw production” from other sources.

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• applebusch@lemmy.blahaj.zone ⁨4⁩ ⁨days⁩ ago

  Using hot air instead of helium would not work. The density of hot air is much higher than helium, so you would need a significantly larger airship to lift the same mass of payload (the useful bits). That and keeping the air hot would require constant energy input reducing the efficiency of the system dramatically. I’m pretty sure that system would be literally impossible to construct.

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  • humanspiral@lemmy.ca ⁨4⁩ ⁨days⁩ ago

    Hydrogen is simply the right lifting gas. Helium not abundant enough for sustainable scale. AFAIK, this model did use H2. Previous protototypes used helium.

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• SaveTheTuaHawk@lemmy.ca ⁨4⁩ ⁨days⁩ ago

  [face Palm].

  JFC people, take a grade 10 physics class.

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  • Hominine@lemmy.world ⁨4⁩ ⁨days⁩ ago

    How about you take a ninth-grade speech class first?

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