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Can Earth's rotation generate power? Physicists divided over controversial claim

nature.com

51–60 of 231 posts

Re: Can Earth's rotation generate power? Physicists divided over controversial claim

#51

It's incredible the lengths humanity is willing to go to avoid adopting nuclear energy - despite the US navy driving mobile reactors millions of miles over the last 70 years.

The Navy isn’t constrained by economics. Nuclear doesn’t make sense economically compared to things like solar and batteries.

Re: Can Earth's rotation generate power? Physicists divided over controversial claim

#52
post #14

Earlier quoted context omitted.

[flagged]

I don't see a problem with the LLM answer. The field near an FM station can reach 100mV or more. The maximum safe exposure levels for general public at 100MHz is 30V/m according to standards.

It's easy to lose a sense of scale in a field which usually works in logarithmic scales. Signals can easily vary by more than 40dB, and it's easy to forget that's a factor of 100 already, and another 40-60dB is not crazy in edge cases. (OTOH ~100uV is a much better estimate of what you'll be seeing from a 'good' FM radio signal)

Re: Can Earth's rotation generate power? Physicists divided over controversial claim

#53
post #25

Wouldn'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)

The IERS will never stand for this!

Re: Can Earth's rotation generate power? Physicists divided over controversial claim

#54

It's incredible the lengths humanity is willing to go to avoid adopting nuclear energy - despite the US navy driving mobile reactors millions of miles over the last 70 years.

Many countries would have to buy nuclear fuel from other countries much like they do for gas and oil. On the other side very few countries can build their own solar panels so it seems the same sort of problem. However if you accept to depend from potential hostile countries at least solar panels don't do much harm when they fail and it takes very little effort to install the equivalent amount of power of a nuclear power plant. If we only could all get along and have a global power grid with always 12 hours of sunshine on it.

Re: Can Earth's rotation generate power? Physicists divided over controversial claim

#55

It's incredible the lengths humanity is willing to go to avoid adopting nuclear energy - despite the US navy driving mobile reactors millions of miles over the last 70 years.

The Navy isn’t constrained by economics. Nuclear doesn’t make sense economically compared to things like solar and batteries.

> things like solar and batteries.

Magnets too - let's just go magnets everywhere.

Reality is solar isn't viable everywhere. And it's not optimal to put it in places where you use the sun to grow food.

We should follow a holistic approach.

* Wind where it's windy.

* Solar where it's sunny - ideally on buildings/away from farms.

* Hydro where possible.

* Nuclear where it makes sense, i.e. stable geography, low occurence of natural disasters, lots of land.

* Some natty gas plants for overflow - not saying commission new ones or prioritize natty, but it's sensible to utilize existing peaked plants.

I'm not a big fan of large scale battery storage solutions, but they can work sometimes. I think they're more sensible for residential/commercial use and, when paired with solar, can really help add robustness to the grid. But, for mega energy storage, I think hydro based solutions are more sensible.

Re: Can Earth's rotation generate power? Physicists divided over controversial claim

#57
post #54

It's incredible the lengths humanity is willing to go to avoid adopting nuclear energy - despite the US navy driving mobile reactors millions of miles over the last 70 years.

Many countries would have to buy nuclear fuel from other countries much like they do for gas and oil. On the other side very few countries can build their own solar panels so it seems the same sort of problem. However if you accept to depend from potential hostile countries at least solar panels don't do much harm when they fail and it takes very little effort to install the equivalent amount of power of a nuclear po…

Until we solve the storage problem, the manufacture of batteries required to store solar power at night and during other low generation times is actively doing harm even without failing.

I don’t think this invalidates your point but I do think it is incredibly important to recognize that environmental harm done slowly over time is no less impactful than that done by a disaster.

Re: Can Earth's rotation generate power? Physicists divided over controversial claim

#58
post #48

Earlier quoted context omitted.

The earths rotation creates it. Or was this rhetorical.

No, it was a serious question. Does anything that rotates create a magnetic field even if it is not an electrical material?

The iron core but there are many open questions https://news.mit.edu/2020/origins-earth-magnetic-field-myste...

Re: Can Earth's rotation generate power? Physicists divided over controversial claim

#59
post #48

Earlier quoted context omitted.

The earths rotation creates it. Or was this rhetorical.

No, it was a serious question. Does anything that rotates create a magnetic field even if it is not an electrical material?

In case of Earth, Wikipedia describes [1] it as being "[..] generated by electric currents due to the motion of convection currents of a mixture of molten iron and nickel in Earth's outer core". This makes Earth a geodynamo [2]. (The aforementioned Wikipedia page is actually really long and detailed, a lot more than I would have thought)

[1] https://en.wikipedia.org/wiki/Earth%27s_magnetic_field [2] https://en.wikipedia.org/wiki/Dynamo_theory

Re: Can Earth's rotation generate power? Physicists divided over controversial claim

#60

My Stupid Question, please don't laugh: If you did this on a massive enough scale, to generate serious amounts of power, would that accidentally slow the Earth's rotation down over time?

> would that accidentally slow the Earth's rotation

No. Incidentally :)

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