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Nuclear is back on the table for a green future

nytimes.com

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Re: Nuclear is back on the table for a green future

#811

Post by pfdietz »

WalterBright wrote: post #797
pfdietz wrote: post #796

Earlier quoted context omitted.

Pumped hydro doesn't require a stream, since it isn't harvesting energy from a preexisting flow of water.

How are you going to create a large enough pond?

This involves moving earth in places with suitable topography. The economics depends on both the vertical offset between the two reservoirs, and how much earth has to be moved per unit of reservoir volume.

Algorithms have been created to use GIS data to automatically find potential PHES sites. There are lots of candidates. Australia, for example, has 300x more potential that it would need for a 100% renewable grid.

http://re100.eng.anu.edu.au/global/

Re: Nuclear is back on the table for a green future

#812

Post by sanderjd »

ncmncm wrote: post #775
sanderjd wrote: post #756

Earlier quoted context omitted.

I think my assumption with pumped hydro is that there must be something holding it back because it's been mature for a long time, so if it were as useful and scalable as you say, I think it would have been scaled a lot more by now.

The overwhelming majority of utility-scale storage today is pumped hydro. It stores and releases many GWh every day. You don't hear much about it because it just works.

Yes but is still a small amount of energy relative to total demand and there don't seem to be serious efforts to scale it up massively. I don't claim to know why there aren't. Maybe there should be. It just makes me suspicious when I see a mature technology that still sees limited deployment, that there is a good reason for that.

Re: Nuclear is back on the table for a green future

#813

Post by ncmncm »

WalterBright wrote: post #797
pfdietz wrote: post #796

Earlier quoted context omitted.

Pumped hydro doesn't require a stream, since it isn't harvesting energy from a preexisting flow of water.

How are you going to create a large enough pond?

Often there is already a depression you can use as is. Or deepen, and use the excavation for a dike.

If not, maybe there is a box canyon you can close the end of with a dam.

In places, they have flattened a convex hilltop and used the material to make a dike.

Usually you don't need anywhere near as much storage volume as a typical hydroelectric dam reservoir holds.

Re: Nuclear is back on the table for a green future

#814

Post by Manuel_D »

_Tev wrote: post #810
dane-pgp wrote: post #437

Earlier quoted context omitted.

Yes, I realise that. That's why I said "I don't know" and "for comparison". My point was that GWh-scale thermal battery proposals would be competing with already existing (and possibly cheaper) chemical batteries, and that energy storage on this scale is not unheard of.

The point is that current energy storage facilities are too small for fully renewable grid (or arguably even 60% renewable grid). Even as a nuclear supporter I would welcome more renewables if we had cheap scalable storage, which no one has it seems. (at least no one pointed out such project in the entire thread)

A minor caveat: some regions have large hydroelectric generation, which doubles as a great energy storage site. Countries seem to be able to manage a roughly 1:1 ratio between intermittent sources and hydroelectric generation. Sweden is managing to decarbonize it's grid with ~1/3rd each of nuclear, intermittent sources, and hydroelectric.

But for much of the world what doesn't have this option, nuclear remains the most viable energy source.

Re: Nuclear is back on the table for a green future

#815

Post by schiffern »

Manuel_D wrote: post #761
thehappypm wrote: post #757

Earlier quoted context omitted.

You’d think so but in reality extraction costs just drop as technology improves. For example, lithium..

Lithium prices have more than doubled over the last decade: https://www.metalary.com/lithium-price/ They've increased more than sixfold since 2000.

"Past performance does not indicate future returns."

All you're doing is repeating the fact that we've been under-investing in lithium (and other energy minerals[0]) for the past decade+. Everyone already knows that.

Nothing indicates lithium mining & refining is at its physical or technology limits. Far from it: we see large low-hanging fruit for process improvements in both.

Ion exchange and/or membrane and/or electrochemical separation vs ponds, lithium carbonate intermediate vs lithium hydroxide, clay vs spodumene, etc. Lots of exciting stuff going on!

[0] https://youtu.be/Keja23R2N7g

Re: Nuclear is back on the table for a green future

#816

Post by belorn »

adrianN wrote: post #780
belorn wrote: post #723

Earlier quoted context omitted.

Since you are 100% certain that such technology will emerge in an economical viable state to solve the storage problem for Europe, could you please provide a date so we can draft a EU law that forbids burning of fossil fuel in the European market by that date. If you can do it by this winter it would solve inflation, enable a complete sanction packet against Russian oil and gas, solve several political conflicts with…

If we had completely free, 100% efficient grid scale storage of unlimited capacity today we couldn't stop burning fossil fuels because we don't have enough renewable generation capacity installed to fill any form of storage.

If the storage solution is close to free then the capacity doesn't matter since any new investment would be guarantied profit. Wind, when the weather is optimal, is several time cheaper than fossil fuels. Everyone would rush to just install new renewable capacity.

Just this week in Europe, during the summer vacations and when energy usage is at the lowest point during the year, the energy market price still jumps by 3000% when the wind go from high to low.

Re: Nuclear is back on the table for a green future

#817

Post by _Tev »

Manuel_D wrote: post #814
_Tev wrote: post #810

Earlier quoted context omitted.

The point is that current energy storage facilities are too small for fully renewable grid (or arguably even 60% renewable grid). Even as a nuclear supporter I would welcome more renewables if we had cheap scalable storage, which no one has it seems. (at least no one pointed out such project in the entire thread)

A minor caveat: some regions have large hydroelectric generation, which doubles as a great energy storage site. Countries seem to be able to manage a roughly 1:1 ratio between intermittent sources and hydroelectric generation. Sweden is managing to decarbonize it's grid with ~1/3rd each of nuclear, intermittent sources, and hydroelectric. But for much of the world what doesn't have this option, nuclear remains the mo…

Yes, that's what I meant by "scalable". You can't just continue picking low hanging fruit forever.

Btw even the Sweden example uses nuclear for decarbonization of the grid ...

Re: Nuclear is back on the table for a green future

#818

Post by trashtester »

basicplus2 wrote: post #596
trashtester wrote: post #315

Earlier quoted context omitted.

EVERYTHING around us is contaminated in some way or another. We are constantly bombarded by cosmic radiation with doses far in excess of the expose you will get from eating those mushrooms. Below 100mSv, there is "no evidence" that exposure leads to any elevation of cancer risk. At levels covered by the article, ie 1000Bq/kg / 80000 Bq/mSv = 0.0125 mSv/kg. In other words, you can eat 8 tons of those mush before there…

These different radiation types are NOT equivalent.

The purpose of the Sievert scale is precisely to to provide a measure that enables equivalent comparisons of radiation doses:

https://en.wikipedia.org/wiki/Sievert

Even if it's not perfectly accurate, it's probably quite close.

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