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

nature.com

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

#221

Post by SecretDreams »

Certhas wrote: post #218
SecretDreams wrote: post #209

Earlier quoted context omitted.

> But to pretend like nuclear can magically become cheaper through technical breakthroughs, while storage is an unsolvable problem is disingenuous. I didn't say storage was not solvable and I even gave a better storage solution than your silly "batteries" example. > Based on the projections for adopted climate scenarios, the average annual energy loss of the global nuclear fleet is estimated to range between 0.8% and…

What silly batteries example? If seasonal storage is solvable, solar + wind is not unreliable. And no, I don't have an anti nuclear agenda. But I know the energy system models and the results, and just how difficult integrating nuclear into the mix is. https://nworbmot.org/blog/burden-of-proof.html Finally, I know exactly what the paper says but maybe you don't: the problem with Dunkelflaute events is correlation. If…

> Finally, I know exactly what the paper says but maybe you don't: the problem with Dunkelflaute events is correlation. If it's cloudy somewhere and the sun is shining elsewhere, then no problem. These problematic conditions for nuclear are the same: large scale spatial correlated.

Great. We'll just pipe over the energy from Arizona to Michigan, should be fine.

Large scale weather events drop nuclear by 1% long term. What percentage do they do for solar?

I'm not even a solar hater - I love solar... On residential and commercial rooftops. Or in sunny and void of life areas.

I love a mix. And nuclear integrates just fine into the mix. Look at a province like Ontario where 60% of the energy is derived from hydro and nuclear. An incredible and robust baseline power with low downtime and, correspondingly, cheap power for all of the residents of that province.

Even more energy from solar and wind too, with some natty gas as top off. Seems to work just fine for them - and with long winters and plenty of cloudy days, solar as a big component of their energy mix seems pretty silly to push for. You can see the mix live below.

https://live.gridwatch.ca/home-page.html

It was 53% nuclear and 28% hydro at the time of me posting this. 16% natty, 4% wind, and 0.1% solar. The solar was good for 21 MW and the nuclear was good for 9600 MW for perspective. Their nuclear has been safe as hell and has run flawlessly for I think 30+ years.

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

#222

Post by logifail »

antod wrote: post #186
logifail wrote: post #77

Earlier quoted context omitted.

Reminds me of a glorious question from undergraduate physics: Calculate the change in the length of the Earth's day if the UK were to switch to vehicles driving on the right-hand side of the road rather than the left..

Is that due to all the roundabouts switching direction relative to the Coriolis effect? Hence the relevance of the UK? Presumably without roundabouts it's all random directions and balanced? Or am I barking up the wrong tree?

It was indeed all about the roundabouts. I forget the details but I do know it took us quite a while to get there(!)

Those tutorials filled me with dread at the time, but with hindsight they were - how can I put this - a fairly formative experience.

Watching your tutor use paper and pencil - and estimation - to calculate something like that was actually quite inspiring. That was, once it stopped being terrifying.

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

#223

Post by DriverDaily »

Detrytus wrote: post #181
DriverDaily wrote: post #130

Earlier quoted context omitted.

Can we put energy in to speed it up? That way a day can be 24 hours exactly instead of 23 hours, 56 minutes, 4 seconds, etc...

Don’t follow your logic: if the day is currently shorter than 24 hours we need to slow the Earth rotation down, not speed it up.

You’re right, I had that backwards

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

#224

Post by grepfru_it »

AtlasBarfed wrote: post #179
grepfru_it wrote: post #63

Earlier quoted context omitted.

Solve the waste problem and you solve nuclear. Waste is still the giant elephant in the room and a lot of people have a fifth grade solution to the problem (we will bury it under ground! We will fly it to the sun! We will resuse it until it is no longer radioactive!) I used to have a neighbor who worked for the DOE, all of the viable solutions are blocked by people who don’t want it in their backyard. Can’t really mo…

Lftr! Breeds burns almost all the fuel.i think the waste products it does make are shorter term.

300-700 years is still many many generations. Remember waste will continue to be produced, during this time.

It’s not a simple fix :)

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

#225

Post by grepfru_it »

kjkjadksj wrote: post #110
grepfru_it wrote: post #63

Earlier quoted context omitted.

Solve the waste problem and you solve nuclear. Waste is still the giant elephant in the room and a lot of people have a fifth grade solution to the problem (we will bury it under ground! We will fly it to the sun! We will resuse it until it is no longer radioactive!) I used to have a neighbor who worked for the DOE, all of the viable solutions are blocked by people who don’t want it in their backyard. Can’t really mo…

What problem with the waste? Reactors are working and generating power today for many thousands of americans. Whatever is being done with waste today seems to work well enough to continue reactor operations without any major headlines. Just seems to be a bit of cognitive dissonance here between what is claimed online and what we see today out in the field generating power.

Current waste takes tens of thousands of years to stop being radioactive. Until then we need to hide it from all living life. In the meantime we continue to create waste.

We are getting better shrinking from thousands to a single thousand.. but we still create waste while we argue where to store the new waste.

It doesn’t scale.

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

#226

Post by grepfru_it »

fallingknife wrote: post #78
grepfru_it wrote: post #63

Earlier quoted context omitted.

Solve the waste problem and you solve nuclear. Waste is still the giant elephant in the room and a lot of people have a fifth grade solution to the problem (we will bury it under ground! We will fly it to the sun! We will resuse it until it is no longer radioactive!) I used to have a neighbor who worked for the DOE, all of the viable solutions are blocked by people who don’t want it in their backyard. Can’t really mo…

Burying the waste is an excellent solution. We are currently dealing with the much more dangerous problem of hydrocarbon combustion waste by releasing it into the atmosphere.

It’s an equally bad solution. Let’s learn from our mistakes yeah? :D

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

#227

Post by pmontra »

bmacho wrote: post #202
pmontra wrote: post #54

Earlier quoted context omitted.

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…

You can do solar energy with mirrors (the ancient Greeks were able to produce that) and steam turbine/stirling generator.

Yes https://en.wikipedia.org/wiki/Concentrated_solar_power but that's not something anybody can install at home.

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

#228

Post by aeternum »

mr_mitm wrote: post #213
aeternum wrote: post #200

Earlier quoted context omitted.

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 p…

Because 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.

There is interaction with other stellar bodies. Massive and uneven amounts of thermal radiation from the sun. Black body radiation out.

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

#229

Post by mr_mitm »

aeternum wrote: post #228
mr_mitm wrote: post #213

Earlier quoted context omitted.

Because 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.

There is interaction with other stellar bodies. Massive and uneven amounts of thermal radiation from the sun. Black body radiation out.

Sure. I'm not going to perform the computation, but my physical intuition tells me that it's completely negligible. The amount of thermal energy the earth absorbs or emits per year must be dwarfed by several orders of magnitudes compared to the rotational energy or the energy lost via tidal friction.

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

#230

Post by AtlasBarfed »

grepfru_it wrote: post #224
AtlasBarfed wrote: post #179

Earlier quoted context omitted.

Lftr! Breeds burns almost all the fuel.i think the waste products it does make are shorter term.

300-700 years is still many many generations. Remember waste will continue to be produced, during this time. It’s not a simple fix :)

Lftr is supposed to be in the high nineties allegedly of fuel consumption %.

And the gas/liquid nature means separation and processing is a lot more viable

Contrast that with solid fuel rods using like 20% of its fuel, and that only of the fissile uranium isotopes. The the waste is locked in a solid form of the spent fuel rods

I'll take lftr which (theoretically) is so much cleaner.

Fusion isnt without waste, the high speed neutrons irradiate/transmute the reactor

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