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First new US nuclear reactor in decades enters commercial operation in Georgia

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Re: First new US nuclear reactor in decades enters commercial operation in Georgia

#351

Post by Manuel_D »

pfdietz wrote: post #346
Manuel_D wrote: post #256

Earlier quoted context omitted.

Again, the energy density of uranium is such that even if seawater extraction remains expensive, it has negligible impact on nuclear power costs: https://en.m.wikipedia.org/wiki/Economics_of_nuclear_power_p... > The cost of raw uranium contributes about $0.0015/kWh Even if this increases by an order of magnitude, this is not significantly impacting the cost of nuclear power. Heck, even two orders of magnitude still a…

If lithium increased in price by 100x, we'd switch over to one of the many other options for energy storage. If uranium increases in price by 100x, burner reactors are screwed (well, even more screwed than they already are.)

"many other options" like what? You can't just say we'd use alternatives and then neglect to specify what those alternatives are. All storage options available to us fall short. Hydropower is geographically limited. Batteries are in too short supply, and are mostly being directed to other applications. Plans for a mostly intermittent grid invariably call for hydrogen, compressed air, giant flywheels, or something else to solve the storage problem. We have no practical experience building electric storage with these systems, so it's effectively a giant hand-wave.

A plan that's dependent on something like hydrogen electric storage is like a plan calling for widespread deep-drilled geothermal power: We have plenty of experience with drilling, and steam turbines. Iceland has plenty of geothermal power - but it sits right on a fault line. That's no guarantee we'll actually be able to build geographically-independent geothermal power. Would you view a plan that involves widespread installation of geothermal power as feasible?

Re: First new US nuclear reactor in decades enters commercial operation in Georgia

#352

Post by pfdietz »

Manuel_D wrote: post #351
pfdietz wrote: post #346

Earlier quoted context omitted.

If lithium increased in price by 100x, we'd switch over to one of the many other options for energy storage. If uranium increases in price by 100x, burner reactors are screwed (well, even more screwed than they already are.)

"many other options" like what? You can't just say we'd use alternatives and then neglect to specify what those alternatives are. All storage options available to us fall short. Hydropower is geographically limited. Batteries are in too short supply, and are mostly being directed to other applications. Plans for a mostly intermittent grid invariably call for hydrogen, compressed air, giant flywheels, or something els…

There are many chemistries for batteries. We're even seeing some of them pushed to commercialization. Chemistries based on common elements like sodium or iron would evade concerns about material availability.

There are thermal storage technologies. An example is pumped thermal storage. This involves (1) adiabatically compressing argon, (2) transferring heat from the compressed argon to a hot store (say, molten "solar salt", a potassium/sodium nitrate salt mix) by a countercurrent heat exchanger, (3) expanding the cooled argon back to the initial pressure, (4) using that now cold argon to extract heat from a "cold store", say liquid hexane, cooling it to -100 C. To discharge, reverse this process. Round trip efficiencies similar to pumped hydro could be achieved. The high temperature side of this process is within the creep range of ordinary steel, so no exotic materials are required.

Resistively heated thermal stores would not be quite as efficient (maybe in the low 50s%) and involve higher temperature (~1200 C), but could work with existing gas turbines. Babcock and Wilcox are commercializing this now, using their very nifty direct contact sand/gas fluidized bed heat exchanger. The storage medium here would be ordinary sand, of which there is an unlimited supply.

This last approach also allows an external heat source, such as hydrogen combustion, to act as a backup heat source. So if your thermal stores run out, you can keep running them by burning hydrogen (or some other e-fuel). The marginal capital cost of this capability would be very low, just that of adding a fluidized bed hydrogen combustor to heat the sand.

Re: First new US nuclear reactor in decades enters commercial operation in Georgia

#353

Post by Retric »

Manuel_D wrote: post #349
Retric wrote: post #347

Earlier quoted context omitted.

Excess per day doesn’t mean you get solar power every single second just per day, that’s what batteries are for. > But you can only sacs energy at the rate rainfall refills the dam. > can’t completely shut off You’re completely misunderstanding how dams are used look here: https://en.wikipedia.org/wiki/Hoover_Dam Installed capacity 2,078.8 MW, Capacity factor 23% Minimum flow rate isn’t 0, but is plenty low enough to…

> Excess per day doesn’t mean you get solar power every single second just per day, that’s what batteries are for. ...which would require an enormous and infeasibly large amount of batteries. You're right: overproduction doesn't mean you get power for every second per day. But a grid does need sufficient energy at every single second per day or you have blackouts. This is why overproduction of intermittent sources is…

> ...which would require an enormous and infeasibly large amount of batteries

False, but you can’t substantiate your argument by simply saying the words you need to back it up with something such as actual calculations etc.

> Their rate of recharge is limited

That’s completely irrelevant here. Rainfall is so concentrated in short periods that they often have months of water in reserve and can decide when exactly to release it over that kind of timeframe. 95% of the time there is less water flowing out of a dam than flowing into it. That’s why we build dams.

Re: First new US nuclear reactor in decades enters commercial operation in Georgia

#354

Post by Manuel_D »

Retric wrote: post #353
Manuel_D wrote: post #349

Earlier quoted context omitted.

> Excess per day doesn’t mean you get solar power every single second just per day, that’s what batteries are for. ...which would require an enormous and infeasibly large amount of batteries. You're right: overproduction doesn't mean you get power for every second per day. But a grid does need sufficient energy at every single second per day or you have blackouts. This is why overproduction of intermittent sources is…

> ...which would require an enormous and infeasibly large amount of batteries False, but you can’t substantiate your argument by simply saying the words you need to back it up with something such as actual calculations etc. > Their rate of recharge is limited That’s completely irrelevant here. Rainfall is so concentrated in short periods that they often have months of water in reserve and can decide when exactly to r…

If you want to calculations on just how far short batteries fall, I do so here: https://news.ycombinator.com/item?id=36949165

The rate of recharge is absolutely relevant, because you can't actually capture excess production from intermittent sources. If you're relying on a dam to fulfill periods of non-production, you need a way to put the excess energy during periods of overproduction back into the dam. But a dam can only shut down its turbines, it can't be recharged faster than the rate that rainfall refills it. If you need 40% of your electricity coming from dams during periods of non-production, then you need rainfall sufficient to produce that much energy. It's not like a battery where you can take excess production and store it back in the dam. That's how pumped hydro electric storage works: you run turbines backwards and refill the dam with excess energy. But pumped hydro requires a very specific set of geographic features, and is not easy to scale up.

Re: First new US nuclear reactor in decades enters commercial operation in Georgia

#355

Post by Manuel_D »

pfdietz wrote: post #352
Manuel_D wrote: post #351

Earlier quoted context omitted.

"many other options" like what? You can't just say we'd use alternatives and then neglect to specify what those alternatives are. All storage options available to us fall short. Hydropower is geographically limited. Batteries are in too short supply, and are mostly being directed to other applications. Plans for a mostly intermittent grid invariably call for hydrogen, compressed air, giant flywheels, or something els…

There are many chemistries for batteries. We're even seeing some of them pushed to commercialization. Chemistries based on common elements like sodium or iron would evade concerns about material availability. There are thermal storage technologies. An example is pumped thermal storage. This involves (1) adiabatically compressing argon, (2) transferring heat from the compressed argon to a hot store (say, molten "solar…

Thermal storage has only been used for district heating. There is no commercial electric thermal storage project in existence. Babcock and Wilcox have not broken ground on a prototype thermal electric storage plant, let alone a commercial one. They signed an intellectual property agreement [1], this is not even remotely the same thing as commercialization.

Hydrogen electric storage has issues producing hydrogen without emitting fossil fuels: almost all hydrogen produced today is through steam reformation which emits carbon dioxide. Electrolysis has issues with corroding electrodes, in particular. We've known about electrolysis for decades (centuries?) but its disadvantages have not been solved. Likewise, how long have sodium and iron batteries been on the verge of commercialization? How long did lithium ion batteries take to reach the scale sufficient for EVs? Sources say that they're projection sodium ion batteries to be produced at 20 GWh per year by 2030 [2]. Even if that level of optimism pans out, this is nowhere near a scale sufficient for grid storage.

People still hope for lithium ion batteries to deliver, because it's the best (or least-bad) option and none of the competitors are set to unseat it. And remember, almost all of this battery production is going to EVs and electronics, only a fraction of it is going to grid storage.

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

2. https://cen.acs.org/business/inorganic-chemicals/Sodium-come...

Re: First new US nuclear reactor in decades enters commercial operation in Georgia

#356

Post by Retric »

Manuel_D wrote: post #354
Retric wrote: post #353

Earlier quoted context omitted.

> ...which would require an enormous and infeasibly large amount of batteries False, but you can’t substantiate your argument by simply saying the words you need to back it up with something such as actual calculations etc. > Their rate of recharge is limited That’s completely irrelevant here. Rainfall is so concentrated in short periods that they often have months of water in reserve and can decide when exactly to r…

If you want to calculations on just how far short batteries fall, I do so here: https://news.ycombinator.com/item?id=36949165 The rate of recharge is absolutely relevant, because you can't actually capture excess production from intermittent sources. If you're relying on a dam to fulfill periods of non-production, you need a way to put the excess energy during periods of overproduction back into the dam. But a dam ca…

> If you're relying on a dam to fulfill periods of non-production, you need a way to put the excess energy during periods of overproduction back into the dam. If you're relying on a dam to fulfill periods of non-production, you need a way to put the excess energy during periods of overproduction back into the dam.

I understand your point but it’s based on faulty assumptions.

Simply not using existing water means it’s still there. If you have 10,000$ in your bank account and you don’t buy something you still have the 10,000$. Dams are the same way if you have 20,000 MWh worth of water and can average 20 MWh for the next 1,000 hours then generating 10 MW for the 500 hours of those hours and 30 MW for the other 500 hours hits zero at exactly the same time.

Recharge is important long term but irrelevant in the short term. You might expect to receive water from the spring thaw, but that’s a long way away. Large dams like the hover are built to contain multiple years worth of average flow for a river. It took more than a full year just to collect enough water for them to start generating hydropower.

As to your analysis,

> 500 GWh globally

That’s an outdated estimate for last year even just EV’s broke 500 GWh. “Automotive lithium-ion (Li-ion) battery demand increased by about 65% to 550 GWh in 2022, from about 330 GWh in 2021” https://www.iea.org/reports/global-ev-outlook-2023/trends-in...

Your number was an estimate for 2022 total production made during 2022, and they got it wrong which isn’t that surprising as EV sales ended up 55% from 2021 and average battery sizes also increased. 2023 numbers are hard to estimate for similar reasons.

> Production of batteries may grow in the future

Again, the rates have been increasing by double digits per year for a long time, that’s wildly faster than the increase in electricity demand. We don’t need to talk in hypothetical terms here just current factories already wildly invalidate your calculation let alone any kind of longer term estimates when grid storage may start to pick up.

> 12 hours

As I mentioned that’s a monumental overestimate, but not particularly relevant compared to the first two issues. We can quibble about specifics here but compared to even a 50% EV world grid storage simply isn’t a major factor.

Re: First new US nuclear reactor in decades enters commercial operation in Georgia

#357

Post by Manuel_D »

Retric wrote: post #356
Manuel_D wrote: post #354

Earlier quoted context omitted.

If you want to calculations on just how far short batteries fall, I do so here: https://news.ycombinator.com/item?id=36949165 The rate of recharge is absolutely relevant, because you can't actually capture excess production from intermittent sources. If you're relying on a dam to fulfill periods of non-production, you need a way to put the excess energy during periods of overproduction back into the dam. But a dam ca…

> If you're relying on a dam to fulfill periods of non-production, you need a way to put the excess energy during periods of overproduction back into the dam. If you're relying on a dam to fulfill periods of non-production, you need a way to put the excess energy during periods of overproduction back into the dam. I understand your point but it’s based on faulty assumptions. Simply not using existing water means it’s…

Rate of recharge is the limiting factor of the total amount of energy you can release from a dam without reducing the total amount of water in the reservoir over time. Hoover dam may be able to produce 2GW of power, but if it averages more than 500 MW it will drop in water level over time (actually less than that, since it's already reaching record low fill levels). True, rainfall is not constant throughout the year. But it doesn't really matter in the big picture: the total amount of energy you can produce with the dam without lowering fill levels is fixed, and it isn't changed by overproduction.

Overproduction doesn't help you here: if you have 3 GW of solar energy and 2 GW of electricity demand, you can't use the remaining 1 GW to refill Hoover Dam. If you produce enough solar to meet demand, you can shut off hoover dam's turbines. But if you overproduce - if you produce more energy than the grid needs - it's wasted, you can't use excess energy to refill the dam beyond just shutting off the turbines.

> That’s an outdated estimate for last year even just EV’s broke 500 GWh. "Automotive lithium-ion (Li-ion) battery demand increased by about 65% to 550 GWh in 2022"

Demand, not production. Just under 500 GWh of batteries was produced, a good chunk of demand went unfulfilled. If anything, all your source shows is that grid storage is even more infeasible because we can't even satisfy EV's storage needs.

> As I mentioned that’s a monumental overestimate

No, if anything it's an optimistic underestimate. 12 hours is just enough for diurnal storage. But you also need storage to offset seasonal fluctuations.

Re: First new US nuclear reactor in decades enters commercial operation in Georgia

#358

Post by Retric »

llsf wrote: post #91
krasin wrote: post #27

Earlier quoted context omitted.

Thanks. I can now see how my comment could be misunderstood. My point is that while 4 cents per kWh for 50 years is a very big number in terms of cost overruns and the taxpayers in Georgia will have to eat it, I as a California resident, somehow pay through the nose despite abundant and cheap solar energy, especially during the daytime.

Nuclear power plants now run more than 50 years. We are pushing some to 80 years already. https://www.energy.gov/ne/articles/whats-lifespan-nuclear-re...

A large fraction of all nuclear power plants decommissioned recently didn’t make 50 years.

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

Re: First new US nuclear reactor in decades enters commercial operation in Georgia

#359

Post by smegger001 »

pfdietz wrote: post #221
smegger001 wrote: post #213

Earlier quoted context omitted.

Yes the radioactive decay products of the naturally occurring ore already in the ground naturally are still in the tailings. But they were there already before. With the removal of the uranium the net radioactive material left would be lower the the initial levels though no?

The daughter products will eventually decay away, but it will take a very long time. In particular, radium has a half life of 1600 years. In any case, these are exactly the same daughters as from the decay of uranium in coal, so the argument you are making there is equivalent to an argument that could be made about coal ash.

but in coal they are burning those decay products and putting them into the air to spread around not so with the uranium ore where those decay products go back to the same ground they were dug out of

Re: First new US nuclear reactor in decades enters commercial operation in Georgia

#360

Post by pfdietz »

smegger001 wrote: post #359
pfdietz wrote: post #221

Earlier quoted context omitted.

The daughter products will eventually decay away, but it will take a very long time. In particular, radium has a half life of 1600 years. In any case, these are exactly the same daughters as from the decay of uranium in coal, so the argument you are making there is equivalent to an argument that could be made about coal ash.

but in coal they are burning those decay products and putting them into the air to spread around not so with the uranium ore where those decay products go back to the same ground they were dug out of

Almost all the radioactive elements in coal go into ash, which is not emitted into the air. Do you have some vision of old coal plants where emissions were not controlled?
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