"High-altitude winds between 1,640 and 3,281 feet (500 and 10,000 meters) above the ground are stronger and steadier than surface winds. These winds are abundant, widely available, and carbon-free.

"The physics of wind power makes this resource extremely valuable. “When wind speed doubles, the energy it carries increases eightfold, triple the speed, and you have 27 times the energy,” explained Gong Zeqi "

  • WFloyd@lemmy.world
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    14 days ago

    When wind speed doubles, the energy it carries increases eightfold,

    Edit: I’m wrong, see edit below!

    Huh? Kinetic energy increase is square, not cubic.

    KE=1/2 m v^2

    So every doubling of speed should increase the available kinetic energy by 4 times, not 8. 3 times the speed is 9 times the energy. Granted there are probably some efficiency gains in excess of this at the low end, but as a rule that’s just wrong.

    Edit: Cool, I learned something new! I neglected to consider it in terms of power, just thought about kinetic energy.

    So something like: KE = 1/2 m v^2

    = 1/2 ( rho V) v^2

    = 1/2 ( rho A d) (d/t)^2

    = 1/2 rho A d^3 1/t^2

    Where P = KE/t

    Thus:

    P = 1/2 rho A (d/t)^3

    = 1/2 rho A v^3

    Lots of other aspects I’m sure I have wrong, but I see how the cubic came to be.

    • Beaker@lemmy.blahaj.zone
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      14 days ago

      Increasing the speed increases both the kinetic energy of the wind hitting the turbines and the amount of wind that hits the turbines each second.

    • humanspiral@lemmy.ca
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      13 days ago

      It has to do with type of turbine that uses “airfoil principle”. Your formula works for “cup”/Parachute design, but airfoils/upwind sails are “magic”