I ask, ..... Would Extracting power would have the side effect of slowing down the earths rotation ?
Can Earth's rotation generate power? Physicists divided over controversial claim
191–200 of 231 posts
Re: Can Earth's rotation generate power? Physicists divided over controversial claim
#192Re: Can Earth's rotation generate power? Physicists divided over controversial claim
#193Futurama already did this episode though? It caused the Earth to stop spinning.
Re: Can Earth's rotation generate power? Physicists divided over controversial claim
#194Earlier quoted context omitted.
Eric Nylund's books are uniformly excellent, even (perhaps surprisingly) the Halo tie-ins
Never heard of him
> The novel follows Jack Potter, a computer cryptographer tenured at the fictional Academe of Pure and Applied Sciences in Santa Sierra, California (a city assembled from the ruins of San Francisco.) The story details Jack's first encounter with an alien calling himself Wheeler who apparently wishes to trade information with humanity.
> Accompanied (for a while) by "gene witch" Zero al Qaseem and data paleontologist Isabel Mirabeau, Jack establishes a corporation based around one of the technologies he was traded by Wheeler, but soon finds that there may be more to his dealings with the alien than he bargained for. Traitorous alliances, deceitful propaganda, and shady business practices are frequent elements of the novel.
> "gene witch"
Re: Can Earth's rotation generate power? Physicists divided over controversial claim
#195Earlier quoted context omitted.
This is addressed in the last paragraph of the article: > Even if it works, the method will not generate energy from thin air. It would tap Earth’s kinetic energy and, in doing so, cause the planet’s spinning to slow over time — although only slightly. If the technique provided all of Earth’s electricity needs, which was around 11 trillion watts in 2022, this would slow the planet’s spin by 7 milliseconds over the ne…
> which was around 11 trillion watts in 2022, this would slow the planet’s spin by 7 milliseconds over the next century, the authors calculate. Really puts how small we are on a cosmic scale into perspective. If we did it for a million years at current energy use scale it would shorten our day by about 1.1 seconds.
Wouldn't it extend our day?
Re: Can Earth's rotation generate power? Physicists divided over controversial claim
#196The Earths rotation already generates power for us: wind. It’s why the jet stream only goes one direction.
None of the power comes from the Earth's rotation. Angular momentum is conserved in a closed system.
But it isn't a closed system. Tides transfer angular momentum from earth's rotation to the moon's orbit.
Re: Can Earth's rotation generate power? Physicists divided over controversial claim
#197The Earths rotation already generates power for us: wind. It’s why the jet stream only goes one direction.
> It’s why the jet stream only goes one direction Yet local winds blow in almost every direction. So to access that energy you'd need a structure 5 miles tall.
Or a balloon or kite five miles up.
Re: Can Earth's rotation generate power? Physicists divided over controversial claim
#198Wouldn't this eventually slow down Earth's rotation? The rotational kinetic energy of our planet is 1/5 M * R^2 * w^2 with (approximately) M = 6e34 kg, R = 6.3e6m, w = 7.4e-5 rad/s, which gives approximately 5e36 joules. Yearly we need roughly 3e16 Wh. Yeah ok there's plenty. Woah! (also, I may be off by some orders of magnitude)
This is addressed in the last paragraph of the article: > Even if it works, the method will not generate energy from thin air. It would tap Earth’s kinetic energy and, in doing so, cause the planet’s spinning to slow over time — although only slightly. If the technique provided all of Earth’s electricity needs, which was around 11 trillion watts in 2022, this would slow the planet’s spin by 7 milliseconds over the ne…
Where does the angular momentum go?
Re: Can Earth's rotation generate power? Physicists divided over controversial claim
#199The Earths rotation already generates power for us: wind. It’s why the jet stream only goes one direction.
a substantial amount of wind is also caused by (differential) solar heating: that's why wind doesn't only go in one direction if you've ever spent time at the seashore, the wind comes in off the sea during the day (because of rising thermals on the land side) and blows back offshore at night (because the land cools and the sea is now warmer) that time in between the air is dead-still, and that's when the swarms of gn…
But the earth's rotation makes the solar heating _differential_
Re: Can Earth's rotation generate power? Physicists divided over controversial claim
#200Earlier quoted context omitted.
Isn't friction from the atmosphere already slowing the planet's spin? Many weather effects like hurricanes ultimately derive their energy from a combination of the earth's rotation and thermal/uneven heating effects so I don't see why this is contentions. Like most things, nature is already doing it and has been for millions of years.
No, that's not possible due to conservation of angular momentum. Only tidal effects can transfer some of it to the sun.
Why would angular momentum be conserved? Rotation within an atmosphere should cause friction would should convert angular momentum into thermal loss.
Interestingly, it looks like the upper atmosphere generally rotates faster than the planet, so it could be that the opposite effect actually dominates. IE the uneven heating causes a atmospheric bulge that actually pushes the atmosphere around slightly faster than the planet rotates, thereby slightly contributing to planetary angular momentum.