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Re:Nuclear is back on the table for a green future by ncmncm on Wednesday June 15, 2022 @12:25PM (#31755371)
As has been explained to you numerous times, intermittency is a trivial technical matter that cannot justify diverting capital to nuke construction or operation.

Repeating your falsehoods here does not make them true.

Re:Nuclear is back on the table for a green future by Manuel_D on Wednesday June 15, 2022 @12:31PM (#31755474)
And as has been explained to you numerous times, intermittency is an incredibly difficult problem and cannot be solved without some miraculous storage mechanism that makes energy storage effectively free. It's so trivial to solve, yet you neglect to mention the solution.

As per your previous comments, you assume that hydrogen, compressed air, or some other form of energy storage will be this silver bullet. This is a very risky assumption. We have no cost history for these systems being built at scale. There's a massive difference between writing a white-paper promising a super cheap storage cost, and actually building an energy storage facility and looking at the bill.

Re:Nuclear is back on the table for a green future by bob29 on Thursday June 16, 2022 @12:03AM (#31762349)
Interesting that you can understand this concept when its applied to development of grid-scale storage.

But you think its easier and risk free to develop from where we are to R&D plus supply chain, operating procedures, and workforce for safe and cost effective nuclear power?

Grid storage has no cost history. Nuclear power has a known cost history of being too expensive, and its had trillions of dollars of investment so theres no low hanging fruit.

Grid storage has existing components used in other industries and applications, nuclear power doesn't.

Re:Nuclear is back on the table for a green future by Manuel_D on Thursday June 16, 2022 @01:23AM (#31762681)
The grid storage that has actually been deployed like hydroelectric and battery storage does have cost history. But it's too expensive, and are geographically limited in the case of the former. The grid storage systems like hydrogen electric storage, or ammonia have not been deployed at scale and has no cost history. I'm not inclined to gamble the future of civilization on technologies that we have zero experience building and operating.

By comparison, we have 70 years of experience building and operating nuclear plants. We only need to build 4 nuclear plants for each one we currently have to achieve a 100% decarbonized grid. The cost history of nuclear power shows a clear trend that serial production is cheaper than one off builds.

And you are incorrect about nuclear power not sharing components with existing applications. Nuclear power plants use steam generators, turbines, dynamos, and cooling towers. These are used in other heat engine based power plants.

Re:Nuclear is back on the table for a green future by bob29 on Thursday June 16, 2022 @11:25AM (#31767172)
>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 suppressed by environmentalists. It literally ended the biggest war ever and was pursued for decades afterwards. Unless you know a secret, if its feasible it would have been done.

Re:Nuclear is back on the table for a green future by Manuel_D on Thursday June 16, 2022 @01:48PM (#31768901)
> 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...

Re:Nuclear is back on the table for a green future by bob29 on Friday June 17, 2022 @10:47AM (#31779001)
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 by Manuel_D on Friday June 17, 2022 @07:04PM (#31785581)
The estimates are from the IPCC, not from the nuclear industry. This is stated in the article.
Re:Nuclear is back on the table for a green future by bob29 on Saturday June 18, 2022 @10:45AM (#31790249)
The IPCC did not do primary research. They cite a source. That source did not do primary research, either. The actual data comes from an estimate from the industry itself. The estimates came from costs. Estimating embodied fossil fuel energy based on cost is a not a bad estimation technique except when a huge amount of your supply chain is subsidized.
Re:Nuclear is back on the table for a green future by ncmncm on Thursday June 16, 2022 @03:00AM (#31763227)
And, all more expensive to operate than alternative methods.

Which is why nukes are today uncompetitive, and get less so every day. The cost to build all those nukes would build far more renewable generating capacity and storage, far more than we will need. So, we will instead spend far less and get all the power we need. Existing nukes will shortly be too expensive to continue operating, and will be mothballed. Their eventual dismantling will consume a not insubstantial fraction of our much reduced energy budget.

Re:Nuclear is back on the table for a green future by E39M5S62 on Wednesday June 15, 2022 @03:27PM (#31758131)
I'm not familiar with this area. Can you explain why it's a trivial technical matter, and what the solution(s) are?
Re:Nuclear is back on the table for a green future by ncmncm on Wednesday June 15, 2022 @06:47PM (#31760400)
Many billions of dollars are today going into constructing factories worldwide to produce equipment for storage of numerous kinds. It takes time to build the factories, and then time to run them to build out the storage capacity.

There is, thus far, little use for storage, because there is not enough renewable generating capacity yet to charge up storage. (Charging it by burning fossil fuels would be stupid.) By the time we need much of it, it will be very, very cheap. In the meantime, building generating capacity and factories is the right use of capital.

Although people insisting there is a problem love to talk about expense of batteries, only a tiny fraction of utility-scale storage will ever be batteries. The cheapest storage is gravity, exemplified by pumped hydro, which represents today almost all utility storage. But there are many variations that all work.

The only uncertainty is which ones will be cheapest. Each is a different mix of build cost, maintenance cost, storage cost, charging cost, and discharging cost, with capex and opex for each. Different users will favor different places on those axes. Best for most uses are those that cost only capex, and store as much energy as you care to, cheaply.

Synthetic ammonia and hydrogen are attractive storage media, despite some higher costs, because they may be sold, and burned in gas turbines.

Liquifying nitrogen is extremely mature tech and, like the synthetic fuels, valuable in its own right. Power is extracted by boiling in ambient air to drive a turbine.

Compressing air underground, adiabatically, is another mature method. Compressing to a sea-floor bladder through a hose from a compressor onshore, likewise. Turbines, again.

Buoyancy, drawing a float down toward a pulley on the sea floor, using a winch onshore; and raising a very, very heavy weight up a disused mine shaft are other, very similar examples of gravity storage. Both have startup time of seconds, and are useful for stabilizing grids. Energy is released by running the winch out, driving a generator.

There are various battery chemistries, for cases where batteries are useful at all. All under consideration are much cheaper than lithium. Farthest along may be iron-air, molten-metal, and sodium-bromide, none of which are prone to fires.

Storage costs of all kinds are falling much faster than solar generating capacity. Utilities will build whatever is cheapest when they finally need any. As prices change, the mix will change. There is no value in picking just one, and plentiful value in using the right one for immediate circumstances.

Nobody needs very much storage, because you can always import and burn fuel. The cheapest fuel will be surplus ammonia and hydrogen, although burning aluminum powder for direct process heat has been used in production at local scales. Scrap aluminum is very cheap.

Re:Nuclear is back on the table for a green future by Manuel_D on Wednesday June 15, 2022 @07:17PM (#31760663)
Note that none of these exotic storage systems have ever actually been deployed commercially. Yes, liquid nitrogen is used for things like cooling. But no one has deployed a grid-scale storage system using liquid nitrogen. Liquid hydrogen has been used in rocket launches, but has not been used for energy storage. These technologies are mature in applications besides energy storage. They are not at all mature in the context of energy storage. Grid-scale storage systems using these technologies remains the stuff of prototypes and white papers.

This commenter is also incorrect in the claim that there is not enough renewable capacity to charge up storage. California , Hawaii, and other energy markets often hit days of excess renewable production. Proponents of energy storage promised that companies would swoop in to store and resell this excess energy. But this has not materialized, because energy storage is not nearly so simple or cheap as this commenter claims it is.

Re:Nuclear is back on the table for a green future by ncmncm on Wednesday June 15, 2022 @07:28PM (#31760753)
You can insist until you are blue in the face that these are all untried and exotic, but you will be wrong throughout. And you know you are wrong as you say it.

If in fact they were exotic and untried, billions of dollars would not already be committed to factories to produce them in industrial volume. The processes involved are used industrially billions of times worldwide every day.

You only wish they were exotic because you imagine it would make nukes more appealing. But nothing can make nukes appealing. They get less so with each passing day.

Re:Nuclear is back on the table for a green future by Manuel_D on Wednesday June 15, 2022 @07:37PM (#31760825)
> If in fact they were exotic and untried, billions of dollars would not already be committed to factories to produce them in industrial volume. The processes involved are used industrially billions of times worldwide every day.

Yes, for purposes different from energy storage. The massive amounts of ammonia synthesized through the Haber process for fertilizer production does nothing to demonstrate ammonia's viability for electric grid storage.

Likewise the hydrogen used in space rockets has no bearing on the feasibility of electrolyzing water, storing the hydrogen, and converting it back to electricity. If anything, the fact that most hydrogen is produced through steam reformation highlights the difficulties of electrolysis at scale.

We have plenty of experience with flywheels. Almost every car has a flywheel in it. Does that mean it's guaranteed to be extremely cheap and scalable to store electricity by spinning a bunch of giant flywheels? That's the kind of leap you're making here.

When someone actually builds and operates a facility that takes in electricity, produces ammonia, and then taps that stored ammonia to produce electricity later, then we can actually measure real-world cost of such a storage system. Until then, it's just optimistic predictions. And optimistic predictions don't actually store any energy.

[dead]
Re:Nuclear is back on the table for a green future by Manuel_D on Thursday June 16, 2022 @01:40AM (#31762760)
> 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 processes, unchanged, to new purposes. But engineers are not idiots. Neither are we.

Those engineers have opted not to build any of the storage systems you listed. I agree they're not idiots.

1. https://www.chemistryworld.com/features/ammonia-synthesis-go...

Re:Nuclear is back on the table for a green future by ncmncm on Thursday June 16, 2022 @03:38AM (#31763437)
Your search skills do not define the limits of investment or build-out.
Re:Nuclear is back on the table for a green future by Manuel_D on Thursday June 16, 2022 @11:07AM (#31766923)
There are no ammonia electric storage plants under construction. You write that there's many under construction, all over the world. Yet you fail to identify one such plant that's actually under construction.
Re:Nuclear is back on the table for a green future by ncmncm on Thursday June 16, 2022 @03:50PM (#31770140)
Ammonia synthesized electrically is not restricted in how it may be used. Identically the same ammonia will be used for many things: burned in combined-cycle turbines for power, burned in retrofitted cargo ships displacing bunker oil, made into fertilizer, injected as working fluid into warehouse-scale refrigeration systems, dissolved in water for window cleaner, used as feedstock in a thousand other chemical pipelines, sent abroad in tankers, mixed into hydrogen fuel to scavenge NOx. It is exactly its wide usefulness that makes it attractive. Similarly for hydrogen.

Insisting that a synthesis plant must jealously direct every last liter produced to be tanked and later burned in a local peaker turbine is fetishism. The ammonia doesn't care, and neither does the synthesis equipment owner: any customer who pays is a good one.

Re:Nuclear is back on the table for a green future by pfdietz on Wednesday June 15, 2022 @07:59PM (#31760980)
Every air separation plant (you know, the kind used to make oxygen for steelmaking) employs expanders for recovering energy from cryogenic nitrogen. This is an off the shelf technology.
Re:Nuclear is back on the table for a green future by Manuel_D on Wednesday June 15, 2022 @08:14PM (#31761088)
It's off the shelf technology for chemical processes. It's not off the shelf technology for energy storage.

We have plenty of experience with flywheels. I bet there's millions of cars built every year that have a flywheel in them. Does that mean energy storage using giant flywheels is guaranteed to be insanely cheap and way cheaper than the existing storage systems?

Just because we have plenty of experience using a given technology in one application doesn't mean it's guaranteed to be a smash hit in a different application.

Re:Nuclear is back on the table for a green future by pfdietz on Wednesday June 15, 2022 @08:21PM (#31761131)
Air separation is not a chemical process. It's a physical process, involving compression, heat exchangers, and expanders. You know, just like an energy storage system using cryogenic gases. None of this is magical unknown technology. The components are literally in use today and have been for years.

Now, whether LN2 (or LAir) energy storage is practical is another matter. The efficiency seems poor unless you have a source of waste heat to juice the process.

Re:Nuclear is back on the table for a green future by Manuel_D on Wednesday June 15, 2022 @08:25PM (#31761156)
Air separation is mostly used for chemical processes [1] to isolate certain gases like oxygen or nitrogen. This is what I wrote in my previous comment:

> It's off the shelf technology for chemical processes. It's not off the shelf technology for energy storage.

The while point I'm making in these last few comments is that just because a certain technology is effective for one application doesn't guarantee it's effectiveness for a different application.

1. https://en.wikipedia.org/wiki/Air_separation#Applications

Re:Nuclear is back on the table for a green future by pfdietz on Wednesday June 15, 2022 @08:32PM (#31761194)
So what if it's used for chemical processes? To make it efficient, there is careful transfer of heat from the input stream to the outgoing streams, with compression/expansion to convert the heat energy back to work. Making this efficient involves just the kinds of components that are needed in a cryogenic energy store.
Re:Nuclear is back on the table for a green future by Manuel_D on Wednesday June 15, 2022 @09:03PM (#31761432)
You correctly point out that air separation is made efficient by transferring the heat from the output stream to the input stream. After cooling air enough to isolate whatever chemical is needed (like nitrogen) the cold output stream is run back through the warm input stream to help cool the input stream. This also has the effect of warming the output stream back to ambient temperature. This is fine if you're separating out oxygen to use in a smelter, or nitrogen to be used in the haber process.

But you can't do this for cryogenic air storage. The whole point is to produce liquid nitrogen (or liquid air) that can be stored and then reheated later to drive an engine to generate electricity. If you ran the liquid nitrogen output through the input stream like in typical air separation, you'd warm the output stream and turn it back into a gas. So even though the two systems both involve cooling systems they're actually substantially different processes. One of them is separating air's constituent gases, and mixes the input and output streams to achieve efficiency. The other is essentially a big liquid nitrogen plant.

Unfortunately the only existing cryogenic air storage plant delivered 15 MWh of storage at a cost of 8 million pounds [1]. That's about $650 per KWh, as compared to ~$130 per KWh for battery storage. Like I said, just because a technology is effective in one application, doesn't mean it's guaranteed to be effective in another one.

1. https://en.wikipedia.org/wiki/Cryogenic_energy_storage#cite_...

Re:Nuclear is back on the table for a green future by pfdietz on Wednesday June 15, 2022 @09:36PM (#31761637)
You tell me: which component of a cryogenic energy storage system is not already in use in some process (air separation or otherwise)? One of the attractions of this sort of thing is it's composed entirely of things that are already quite mature, and that have existing supply chains.
Re:Nuclear is back on the table for a green future by Manuel_D on Wednesday June 15, 2022 @09:46PM (#31761693)
And for the third time, just because the individual components are used in different applications doesn't mean it's going to be cheap or scalable to use them in energy storage. The cost history of existing cryogenic storage plants indicates that no, it's not effective for energy storage it's 4-5x more expensive.

We build plenty of flywheels. Does that mean energy storage based on giant flywheels is guaranteed to be efficient at scale because we have experience using flywheels in other applications like automobiles?

Re:Nuclear is back on the table for a green future by pfdietz on Wednesday June 15, 2022 @11:03PM (#31762098)
You're changing the subject now. You were criticizing these for lack of maturity, not for being uneconomical. My point is that your criticism that they aren't mature is misplaced, since the component technologies are all well established. Of course, it could be LN2 or LAir storage doesn't compete.
Re:Nuclear is back on the table for a green future by Manuel_D on Wednesday June 15, 2022 @11:09PM (#31762122)
No, my criticism of the lack of maturity of cryogenic air energy storage is still correct. The fact that it shares some components with air separation does not change the fact that cryogenic air storage is not mature technology.

Similar deal with ammonia energy storage. We've got plenty of experience with synthesizing ammonia for fertilizer production. We've got very little, if any, experience using synthesized ammonia as a form of energy storage.

It was you, not I, that started this tangent about air separation in this comment [1]. I was, from the beginning, talking about energy storage systems.

1. https://news.ycombinator.com/item?id=31760980

Re:Nuclear is back on the table for a green future by ncmncm on Thursday June 16, 2022 @12:45AM (#31762508)
I.e., you cannot identify any single stage of any of these extremely familiar industrial processes that would make it unsuitable for energy storage or retrieval, so instead invoke ghosts of fear and doubt.

Do you imagine the ammonia knows why it is being synthesized, and would balk at being synthesized and tanked for energy storage or fuel? Do you imagine it will object to being burnt in a combined-cycle turbine?

Your credibility is at zero.

Re:Nuclear is back on the table for a green future by Manuel_D on Thursday June 16, 2022 @01:35AM (#31762737)
Why are you all of a suddenly replying to a super-deep thread? Is pfdietz your alt? Regardless if you're asking about the technical shortcomings of ammonia and cryogenic air storage I'm happy the enlighten:

Ammonia storage would first require a source of hydrogen. Currently almost all hydrogen is produced through steam reformation which releases carbon dioxide. So this has to be replaced with electrolysis, which is more energy intensive and has issues with corrosion of electrodes. Then there's the issue of heating up this hydrogen and nitrogen to ~400C and compressing it to fix the nitrogen into ammonia. Currently this is done through combustion of fossil fuels. That too needs to be replaced with an electric source. All these changes drastically increases the cost of producing ammonia over existing processes.

Cryogenic storage is essentially producing liquid nitrogen by refrigerating air, and then hearing the nitrogen to create a pressure gradient to drive a heat engine. Cooling the air is a huge energy sink, and releasing the energy often has to be coupled with a heat source in order transition the liquid nitrogen to a gas. It's actually using the heat gradient of the ambient air and the liquid nitrogen to drive the heat engine, and that ambient air often doesn't have the required energy density to produce more than a few dozen megawatts. Existing prototypes often scavenge waste heat from a fossil fuel power plant. But again, not an option if you plan to eliminate fossil fuels.

Re:Nuclear is back on the table for a green future by ncmncm on Thursday June 16, 2022 @06:44AM (#31764500)
If heat capacity of air were too low to boil LN2, it would also be too low to condense nukes' operating steam. You don't get it both ways.
Re:Nuclear is back on the table for a green future by ncmncm on Thursday June 16, 2022 @03:13AM (#31763305)
You pretend that electrolysis has not been known for centuries. But nobody is fooled.