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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

#671

Post by ben_w »

ncmncm wrote: post #666
mlyle wrote: post #508

Earlier quoted context omitted.

> Shipping power 2000 miles is absolutely super-practical. DC interconnect makes it more practical, and it's better than storage, but losses and costs accumulate. > China has a project to send it 8000 miles from solar farms they are building in Chile Chile has proposed a project to do just that. It is in exceptionally early conceptual planning stages-- but look at you acting like it's a fait accompli!

Chile does not drive massive energy projects. China is in the driver seat. I doubt it will end up built, but that will not be because it is impractical. It will be because local generation and storage will turn out to be cheaper and less vulnerable to geopolitical upset.

Last time I looked at this, antipodal HVDC was several (2? 3? Can't remember) orders of magnitude cheaper than batteries at the scale of continental electrical requirements; the limit is needing so much metal you become a dominant player in the world metal mining industry just for this project.

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

#672

Post by sandos »

stormbrew wrote: post #564
cycomanic wrote: post #327

Earlier quoted context omitted.

Ok I didn't know that they implemented load following in France. However, note thatbbecause nuclear power cost is almost completely capex dominated so doing this essentially increases your power cost by the factor that you use for load balancing. So out of economic reasons you hardly ever want to not run a nuclear plant at 100%.

Seems like grid scale storage could "solve" this, in precisely the way it does for renewables (ie. Treat nuclear as a sun that shines 24/7 and build storage to allow you to generate a bit above the average and follow the actual usage curve with storage). That is, assuming that grid scale storage is in fact viable.

Yup, but didn't we already say that renewables are cheaper per kWh? So then with any storage renewables should still be the cheap bulk generation.

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

#673

Post by Andrew_nenakhov »

ncmncm wrote: post #662
Andrew_nenakhov wrote: post #435

Earlier quoted context omitted.

Renewables are far from $0 opex, and your statement about 'no reasonable expectation' are somewhat unbased .

Nukes are concrete, steel, pumps, steam turbines, liability subsidy, decommissioning subsidy. None of those get cheaper.

Concrete and steel costs are negligible in the full costs of the nuclear plant. Complex machinery like turbines, reactors, etc have huge costs that fall of rapidly when you start mass producing them. If you make 2 plants/year the cost per item is X, if you make 100 plants/year the cost per item is X/10 or X/20. Huge part of costs goes into machinery that allows to build the thing. Once you have it, producing more parts becomes way easier.

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

#674

Post by adrianN »

megaman821 wrote: post #491
ncmncm wrote: post #467

Earlier quoted context omitted.

Cycle efficiency is trivially resolved by feeding in more zero-opex power. But hydrogen efficiency is improving as fast as all renewable tech.

I agree that hydrogen efficiency doesn't matter here, but the capital expenditure to build a giant electrolyzer with 5% utilization doesn't really make sense. The cost of the electrolyzer is the things that needs to greatly fall if hydrogen is going to be used for long-term storage.

Hydrogen has important industrial uses. Currently we get it from natural gas. That has to change in the future.

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

#675

Post by [deleted] »

worik wrote: post #555
belorn wrote: post #528

Earlier quoted context omitted.

The storage problem has yet to be solved for the same reason why any nation has yet to solve the issue of pollution from fossil fuels. It cost money and any increase in energy costs is detrimental to growth. The insurance issue is similar identical to other energy sources. Why isn't hydro power insured in the case of accidental flooding? If they were it wouldn't be possible to run them at current energy prices. We do…

No. The storage problem has not been solved because we do not have the technology. There is no evidence that the technology os possible. The long term waste (not much in quantity, but it does mount up. A few million litres at the moment I believe ??) has to be stored for periods of time on the order of hundreds of thousands of years. There is no way we can write a warning sign that we know can be read for that long.…

[deleted]

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

#676

Post by ncmncm »

Manuel_D wrote: post #630
ncmncm wrote: post #604

Earlier quoted context omitted.

Quoted post unavailable.

> Electric ammonia synthesis plants are right now under construction all over the world. Source? I'm not finding any result for electric ammonia synthesis plants under construction right now. The best I could find is this [1] but it's not a plant under construction, and there still significant challenges to overcome to make this viable. > You imagine that engineers are idiots who cannot direct existing, familiar proc…

Your search skills do not define the limits of investment or build-out.

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

#677

Post by ncmncm »

mlyle wrote: post #272
ncmncm wrote: post #248

Earlier quoted context omitted.

Renewables' capacity factor is much greater than 10%, in practice. If you need falsehoods to make your case, you have no case.

> > The thing is, 183GW from PV is like 20-30GW of nuclear, because nuclear's capacity factor is near 100% and PV's is often near 10%. > Renewables' capacity factor is much greater than 10%, in practice. If you need falsehoods to make your case, you have no case. Residential/commercial PV -- e.g. rooftop solar-- very often is 10% or less. If you want to only look at utility-scale fixed tilt, instead, recent deploymen…

Nukes' utility factor will fall rapidly as renewables and storage undercut them. Each decrease in utility factor multiplies their per-kWh cost, making them increasingly uncompetitive, and that at a steadily increasing rate.

Nukes will shortly be mothballed, to perhaps be fired up once in a while in response to spiking demand.

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

#678

Post by lelag »

ncmncm wrote: post #665
lelag wrote: post #653

Earlier quoted context omitted.

You make it sound like I'm anti-renewable. I'm not at all. I'm all for building as much capacity as we can as long as it makes economical sense and I will selfishly have solar panel and LFP batteries installed on my home as soon as I can and before price goes up as I expect they will. What I'm saying is that we should not put all of our eggs in the same basket hoping that wind and solar are silver bullets that will f…

They are silver bullets -- really, golden geese -- that are fixing it all, as fast as we spend to build them out. We could be building out much faster, if not for societal inertia and corrupt lobbying. Each dollar spent on nukes is a dollar not spent on radically more productive renewables. Thus, each diverted to nukes brings climate catastrophe nearer.

> Each dollar spent on nukes is a dollar not spent on radically more productive renewables. Thus, each diverted to nukes brings climate catastrophe nearer.

Unfortunately, it seems we have a fundamental and irreconcilable disagreement on this point as I feel exactly the opposite. At least, I'm glad to live in a country where the government mostly share my view on the topic.

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

#679

Post by WalterBright »

qsdf38100 wrote: post #669
californical wrote: post #601

Earlier quoted context omitted.

This is a genius idea, especially because it could be done anywhere with a hill, which makes it a lot more geographically accessible (since most places have hills)

It’s actually not a good idea at all. When you do the math ( or rather the physics) gravity batteries need so much mass and height to compete with other technologies that it’s just not worth it. Except if water, pipes and pumps are used, as water is heavy, and pipes and pumps can transport a lot of it very efficiently and cheaply. That’s called pumped hydro storage and is currently the #1 grid scale storage in the wo…

Well, his company is building a pilot plant in Brazil. I suppose we'll find out if he's a genius or not.

> efficiently

Are you sure about that? He said the losses due to pipe friction were considerable.

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

#680

Post by ncmncm »

qsdf38100 wrote: post #669
californical wrote: post #601

Earlier quoted context omitted.

This is a genius idea, especially because it could be done anywhere with a hill, which makes it a lot more geographically accessible (since most places have hills)

It’s actually not a good idea at all. When you do the math ( or rather the physics) gravity batteries need so much mass and height to compete with other technologies that it’s just not worth it. Except if water, pipes and pumps are used, as water is heavy, and pipes and pumps can transport a lot of it very efficiently and cheaply. That’s called pumped hydro storage and is currently the #1 grid scale storage in the wo…

You need a very, very large mass, and then rails and rolling stock to carry it.

That is why vertical motion in a disused mineshaft is attractive. A single 10,000t weight hanging from a winch has just one moving part, the winch, and cable all in tension, with no preparation of the shaft sides; everything is concentrated at the top. The mineshaft provides isolation from environmental disruption.

You get much the same effect with a float attached to a cable down to a pulley augered into the sea floor; thence to an onshore winch. The cable and pulley are exposed to sea (or lake) water, but you get the advantage that the winch may be shared among as many cable reels as you like, with only simple clutches. A 20m diameter float displaces 4000 tons of water, and the sea floor may be much more than a km deep.

(In principle you could share a winch drive among lots of mineshafts, but they are rarely close enough together. You could bore more, but that drives up cost. The world is absolutely perforated with disused mineshafts.)

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