4 ms·
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 ene
by MathMonkeyMan 2y ago
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 next century, the authors calculate. This is similar to the change in speed caused by natural phenomena such as the Moon’s pull and changing dynamics inside the planet’s core.
- api 2y ago> 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.
- OccamsMirror 2y agoWouldn't it extend our day?
- api 2y agoYes. Had it backwards.
- aeternum 2y agoIsn'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.
- mr_mitm 2y agoNo, that's not possible due to conservation of angular momentum. Only tidal effects can transfer some of it to the sun.
- Jensson 2y agoTidal effects mostly transfers it to the moon, the sun has almost no tidal effects.
- MathMonkeyMan 2y agoTidal effects from the sun are about 46% as strong as those from the moon. <https://oceanservice.noaa.gov/education/tutorial_tides/tides02_cause.html https://oceanservice.noaa.gov/education/tutorial_tides/tides...>
- aeternum 2y agoWhy 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.
- ziofill 2y agoEnergy conservation and momentum conservation are different
- mr_mitm 2y agoBecause the system exhibits rotational symmetry. It follows from Noether's theorem that angular momentum is conserved. Only when you include the interactions with other stellar bodies you lose the symmetry and you have an opportunity to shed angular momentum.
- deleted 2y ago[deleted]
- mmooss 2y agoHow much velocity loss would be needed for an impact on the environment, or on some humans someplace?
- ForHackernews 2y agoIt's kind of insane how much energy is involved in big masses of rock flying around in space.
- thayne 2y agoWhere does the angular momentum go?