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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

#781

Post by qsdf38100 »

WalterBright wrote: post #679
qsdf38100 wrote: post #669

Earlier quoted context omitted.

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.

70% round trop efficiency. And it’s from actual operational data, not from an optimistic spreadsheet calculation.

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

#782

Post by qsdf38100 »

ncmncm wrote: post #680
qsdf38100 wrote: post #669

Earlier quoted context omitted.

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 e…

10,000t weight? If it’s made up of rock with a density of 3000kg/m3, it’s 3333 cubic meters, so about 15x15x15 m3. Basically a large building. I’m not sure what kind of shaft can handle it. And even if you can pull it of, 10000t over 1000 meters is only 27 MWh of storage. 1 pumped hydro plant can store hundred of GWh!

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

#783

Post by Andrew_nenakhov »

ncmncm wrote: post #773
Andrew_nenakhov wrote: post #759

Earlier quoted context omitted.

Are you really arguing that they'd import more gas now if they hadn't shut down the nuclear plants? Everyone including Germans have understood by now that phasing out nuclear was a mistake, but you still repeat that no, gas dependency good, nuclear power independence bad.

Yes. They would be importing more fossil fuels now if they had not built out wind, and had instead spent the money on their reactors.

If they hadn't destroyed their nuclear generation AND created wind&solar, etc, they wouldn't have to import anything from Russia.

For some reason, you (incorrectly) presume that maintaining nuclear energy prevents building wind generators. Also, the money 'spent' on reactors is kinda paid off by customers who pay for the generated electricity.

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

#784

Post by Consultant32452 »

pfdietz wrote: post #585
Consultant32452 wrote: post #570

Earlier quoted context omitted.

Many people support CO2 taxes to raise the price of fossil fuels when gas prices are low. When gas prices are high I see very few people cheering it on or attempting to claim credit for all their great work to raise the price. It's tough to really get that ball rolling if that's your goal due to this marketing issue.

Without CO2 taxes, we're globally screwed. I expect they will be forced through, and confiscatory tariffs on trade with countries that refuse to impose them.

It's hard to say how it will go. It's entirely possible carbon capture will become cheap enough that a couple of rich countries can just capture all the necessary carbon for the whole globe and it will be a rounding error in their budget. Then other countries can burn all the oil/coal they want and it will only be a local pollution problem rather than an existential risk to the globe.

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

#785

Post by bob29 »

Manuel_D wrote: post #737
bob29 wrote: post #729

Earlier quoted context omitted.

>build 4 nuclear plants for each one we currently have to achieve a 100% decarbonized grid Uhh, mining and uranium enrichment and transportation all require fossil fuels, and more fossil fuel energy than a fueled nuclear produces in electrical energy. Increasing 4x nuclear plants would increase fossil fuel consumption in the nuclear supply chain. Nuclear isn't some secret technology you've just discovered thats being…

> Uhh, mining and uranium enrichment and transportation all require fossil fuels, and more fossil fuel energy than a fueled nuclear produces in electrical energy. Incorrect. Nuclear power actually has the second lowest net CO2 emissions per energy source, second only to hydroelectricity. Less than solar and wind: https://en.wikipedia.org/wiki/Life-cycle_greenhouse_gas_emis...

So wrong its funny. Maybe if you assume the pre-existance of the nuclear supply chain due to a weapons program. I challenge you to actually follow the sources on any of estimates like that, or the hilarious "12g c02/kwhr" quote. It's all ESTIMATES (not measurements) FROM The nuclear industry. But keep on believing.

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

#786

Post by ncmncm »

Andrew_nenakhov wrote: post #783
ncmncm wrote: post #773

Earlier quoted context omitted.

Yes. They would be importing more fossil fuels now if they had not built out wind, and had instead spent the money on their reactors.

If they hadn't destroyed their nuclear generation AND created wind&solar, etc, they wouldn't have to import anything from Russia. For some reason, you (incorrectly) presume that maintaining nuclear energy prevents building wind generators. Also, the money 'spent' on reactors is kinda paid off by customers who pay for the generated electricity.

Money is fungible. Each euro spent on one thing is a euro not spent on a different thing.

Electrical power is also fungible. A kWh delivered is a kWh, whether generated on a nuke or in a wind turbine.

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

#787

Post by ZetaZero »

fallingknife wrote: post #411
ZetaZero wrote: post #358

Earlier quoted context omitted.

With Vogtle 3 & 4, the only nuclear plants coming online in the US, the construction costs are now projected to be $30 billion for 2.2 GW. We'd need ~1000 of these size plants to power the US. That's not going to cut it either.

You mathed wrong. You would need a little over 200, but no one is suggesting powering the whole grid with nuclear.

and no one suggested we run the entire grid on PV/batteries, except you.

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

#788

Post by ncmncm »

qsdf38100 wrote: post #782
ncmncm wrote: post #680

Earlier quoted context omitted.

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 e…

10,000t weight? If it’s made up of rock with a density of 3000kg/m3, it’s 3333 cubic meters, so about 15x15x15 m3. Basically a large building. I’m not sure what kind of shaft can handle it. And even if you can pull it of, 10000t over 1000 meters is only 27 MWh of storage. 1 pumped hydro plant can store hundred of GWh!

(1) Rock is not very dense; pig iron density is 3x rock's. (2) A cube is not the only shape, for a weight. (3) Total capacity is not the only parameter of interest, for utility storage. (4) There is not only one mineshaft. (5) No utility is restricted to using only one kind of storage; different kinds favor different parameters, and we may expect utilities to use different kinds at the same time to maximize value and minimize cost.

Assuming utilities will do the stupid, expensive thing leads to failed analyses.

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

#789

Post by pfdietz »

rswskg wrote: post #212
BenoitP wrote: post #139

Earlier quoted context omitted.

> most serious analysis agree that renewables will be about 80% Well, let's see them; and see how much they rely on yet to be proven industrially new storage tech (and without humongous mining activity)

Yep! Once battery storage doesn't pan out(and it won't currently for trucks), I see synth hydrocarbons picking up the transport slack. But that will require alot of energy..

If there is mass production of synfuels, that means mass production of hydrogen (which is either used directly as the synfuel, or used to make the synfuel). And as soon as there's mass hydrogen production, it's an ENORMOUS amount of dispatchable demand, which solves the intermittency problem of renewables (even if the hydrogen is never turned back into electricity.)

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

#790

Post by pfdietz »

outside1234 wrote: post #5
impostervt wrote: post #3

I just finished Bill Gates' "How to Avoid a Climate Disaster". Very good book, and it makes two points (among many others): - To reduce carbon in the air, getting clean electricity is key. If we can do that, we can more easily reduce emissions from other areas. - There are no paths to clean energy by 2050 without nuclear power.

* No paths to nighttime clean energy without nuclear power

Babcock and Wilcox have gotten out of the nuclear business.

What business have they gotten into? Thermal storage of grid energy with a > 50% round trip efficiency. It heats sand with a compact resistive heater, stores the sand in insulated silos, and recovers the energy by a Brayton cycle system with a really interesting and compact fluidized bed heat exchanger. Storage capacity is sized for 100 hours of operation. Not just overnight, but four days.

https://www.babcock.com/home/about/corporate/news/babcock-wi...

Westinghouse is also doing thermal grid storage now. Pumped TES can have a round trip efficiency > 60%.

https://www.energy-storage.news/nuclear-power-company-westin...

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