this post was submitted on 25 Sep 2025
709 points (99.0% liked)

Technology

75645 readers
3368 users here now

This is a most excellent place for technology news and articles.


Our Rules


  1. Follow the lemmy.world rules.
  2. Only tech related news or articles.
  3. Be excellent to each other!
  4. Mod approved content bots can post up to 10 articles per day.
  5. Threads asking for personal tech support may be deleted.
  6. Politics threads may be removed.
  7. No memes allowed as posts, OK to post as comments.
  8. Only approved bots from the list below, this includes using AI responses and summaries. To ask if your bot can be added please contact a mod.
  9. Check for duplicates before posting, duplicates may be removed
  10. Accounts 7 days and younger will have their posts automatically removed.

Approved Bots


founded 2 years ago
MODERATORS
 

"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 "

you are viewing a single comment's thread
view the rest of the comments
[–] WFloyd@lemmy.world 11 points 6 days ago* (last edited 6 days ago) (15 children)

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.

[–] driving_crooner@lemmy.eco.br 26 points 6 days ago (5 children)

Its cubic actually

https://thundersaidenergy.com/downloads/wind-power-impacts-of-larger-turbines/

I don't understand the physics, but every model of power output from wind turbines uses V^3 for the formula

[–] WFloyd@lemmy.world 5 points 6 days ago

Thanks for the correction! I got way ahead of myself.

load more comments (4 replies)
load more comments (13 replies)