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Utopia Talk / Politics / Nuclear power n stuff
jergul
large member
Thu Jan 30 01:37:53
Process heat is needed to produce synthetic natural gas.

Nuclear power plants are quite good at that. Its what they do. Electricity production is a bit coincidental and harvests 35% or so of the thermal heat a nuclear reactor produces.

The process:
Get H2 from Ho2 by adding energy.
Get C from CO2 in seawater by adding energy.
Combine H and C for CH4 by adding energy.
Products with value: H2, O2, CO2 (its surprisingly expensive. Think carbonated water), CH4, H2O (desalinated).

It ultimately amounts to a cogeneration system with variable production of electricity for the grid.

I can see 250MWe (750MWthermal) having a niche here. 250 MWe is half the size Rolls Royce is working on.

My point is that the nuclear industry needs to flip the equation in the UK. Stop thinking of itself as an electricity producer and begin thinking of itself as a heat producer where electricity can be one of several final products.

If it must be subsidised, then subsidise its strengths. In this case, synthetic natural gas.

Market mechanisms will take care of the rest. It is fully capable of diverting electricity to the grid if peak demand pricing indicates that is profitable.
jergul
large member
Thu Jan 30 01:52:29
The key feature here is sunk costs. The UK already has a fantastic natural gas distribution network. So piggyback off that.

It resolves one of the problems with using H2 as a fuel directly. Dependable supply is needed before serious development in use will occur. Serious development in use is needed before dependable supply will occur.

Synthetic natural gas production gives a consistent demand for H2 (in addition, about 10% of H2 could be added directly into pipe system for end consumption either as a fraction of NG directly, or be separated elsewhere and the pipe system being used as a H2 distribution system).

Besides, the UK is not going to meet its 0 net emissions goal without carbon neutral sources of natural gas.

Its the big challenge curiously being ignored.
jergul
large member
Thu Jan 30 03:51:08
Jergulmath because its fun. UK NG use 10 million M3 an hour.

750 MW thermal, conversion efficiency %:

50% - 20 M3/s = 72 000 = 0,72% of NG consumption
60 - 24
70 - 28
80 - 32 = 1,15% of NG consumption

With energy from a single Seb sized small, modular reactor.
Seb
Member
Thu Jan 30 05:07:05
There is one issue with this however - you need to concentrate co2 to get those efficiencies.

So this means capture on burning, which is a problem in households (main consumers of NG if you take power plants out of the equation, which you might as well if using SMR); or cryogenic distillation which murders the efficiency.

You could use this to double the usage of the Ng - extract the stored energy in power plants, capture the CO2, reforma it, then send it off to the grid to be burned in houses.

The truth is that the domestic gas infrastructure either needs to be expanded into a full loop system ($$$$), some hitherto unknown mechanism for capturing carbon that works in domestic settings used, or much more efficient co2 extraction from the air used.

Might as well just use plasma arc to turn biomatter and other organic waste into syngas, or alternatively fermenters.



Seb
Member
Thu Jan 30 05:10:32
Sucking carbon out of the atmosphere needs something more like an artificial leaf. Uses sunlight, floats on water, air blown across it.
Seb
Member
Thu Jan 30 05:12:47
In terms of using the existing gas network, I'd guess using hydrogen might be better.


https://www.sciencedirect.com/science/article/pii/S0360319913006800
jergul
large member
Thu Jan 30 05:43:08
Seb
Not suggesting sucking it out of atmos. Out of seawater. Costs about 70/ton. For the purposes of above, I simply assumed that some energy from the powerplant would be used accessing carbon. I don't care how. Who knows, perhaps the most affordable source is biochar. Produced with nice leafs or blades initially.

10% hydrogen, 90% CH4 works best. I have mentioned that before. A richer hydrogen mix than so would force a complete revamp of much of the pipeline and all of end-use products.

Researchers are myoptic morons sometimes.



jergul
large member
Thu Jan 30 05:46:24
The last was not minted at you.

But if you want to revamp everything, then just phase out natural gas and go full electric.

The solution for meeting 0 net using current gas networks is synthetic natural gas (10% H2, 90% CH4).
seb
Member
Thu Jan 30 06:45:30
CO2 from sea water? What's the process - not familiar with that.

If you can use the atmosphere to close the cycle then that's all fine and dandy.

The other thing to consider is that process heat left after extraction of energy from a nuclear reactor may be low grade (I.e. low temp) - again not immediately familiar with this process - normally ive seen this in terms of cracking methane to H2 rather than reverse, so I'm assuming it's some combination of pressure and temperature that makes it thermodynamically favourable to get H2 and CH4 out (or syn gas mix of CO and H2 that has similar properties to natural gas) - the question is whether the heat left over from the turbines is good for that.

I assume overall (for no other reason that nature is a bitch) that overall the system efficiency will be lower.
seb
Member
Thu Jan 30 07:29:57
Urrgh - sea water extraction 240 kj per mol.

Energy of natural gas is 1300 kj per mol.

This is likely to be absurdly less efficient than just shifting to electrical heat.


Pump storage ftw in tidal lagoons. Helps with flood defences too.
seb
Member
Thu Jan 30 07:31:12
Tidal lagoons covered with artifical leaves.
jergul
large member
Thu Jan 30 07:34:11
I am not sure of the process either. It involves energy use :).

"The U.S. Navy has already developed a prototype seawater capture device. Because CO2 can be converted to fuel by adding energy (and some Navy vessels tend to have spare nuclear reactors on board), such a technology could allow vessels to create their own fuel and avoid having to stop to refuel. Of course, if the captured carbon is converted to fuel and combusted, it just returns to the atmosphere, but future applications of this kind of technology could provide long-term storage for captured carbon."

The number the US is throwing around is 100 000 gallons of aviation fuel per day using surplus energy from 2 nuclear reactors on their carriers.

Process energy from reactors can be as high as you want. Imagine a gas cooled loop with exit temperatures above 500 C. That is not what the US is doing, but design principles change if you highlight process energy ahead of electricity production.

50%-80% is actually pretty low range for a cogeneration system. But fair enough. Say 0.5-1.0% of UK ng needs per reactor.

Its a two step process. Get H2, then combine to get CH4.

You can play around with optimizing the concept a lot. But the basis is sunken costs (the natural gas distribution and consumption network) and poor conversion ratios from thermal to electric for nuclear power plants (35% max).

There is tons of wiggleroom.
jergul
large member
Thu Jan 30 07:42:06
Seb
Nothing is absurdly less efficient than wasting 2/3rds of the energy nuclear power plants produce.

Its at a point where a viable alternative to wasting is making fresh water. Rediculous :).
jergul
large member
Thu Jan 30 08:09:41
"The Sabatier reaction or Sabatier process was discovered by the French chemist Paul Sabatier and Senderens in 1897. It involves the reaction of hydrogen with carbon dioxide at elevated temperatures (optimally 300–400 °C) and pressures in the presence of a nickel catalyst to produce methane and water."

Converting 2H2 to CH4 does significantly increase energy (from 600k to 900k or something like that).

Its a good way to use thermal energy available at any nuclear power plant.

Ultimately, if you believe in H2, then you certainly should believe in CH4. At least for the UK.
seb
Member
Thu Jan 30 11:27:07
Jergul:

Nuclear reactor should be around 60% thermal efficiency!

Point is - depending on exit temp of steam from turbines - if you need higher steam temp because you want to use for some other process, you reduce efficiency of Electricity production. You wind up with more heat, but less electricity.

Can't really analyse without the specifics.
Beware USN research projects - they sunk millions into pollywell fusion. They have more money than sense sometimes and will happily accept crazy projections.

Happy to believe in CH4 in principle. It's the overall efficiency of getting the necessary co2 Vs just electrolysing water, or steam reforming NG into H2 at central locations and capturing the co2.

And at what point the gas infrastructure turns out to be best treated as a sunk cost.

Personally, I'd love to keep Ng domestically available. Much much better than cooking on an electric stove!
jergul
large member
Thu Jan 30 12:30:07
Seb
Its around 33% thermodynamic efficiency. Just another turbine in other words.

PWRs are actually cooled significantly by high volumes of water. There is not problem in principle or practice of using gas cooling, or liquid metal cooling and getting any temperature you want.

But with PWRs, the best solution for current designs is probably just running with a suboptimal Sabatier process with temperatures in the 220 C range. Which is typical current exit temperatures.

The USN is a proof in principle thing.

Getting CO2 is rather trivial as it turns out after a quick google. The energy cost is H2.

I don't think gas infrastucture should ever be considered a sunk cost. Intermittent production from wind and solar suggests H2 should always be made. Its just not very good as H2. Its better as CH4.

And H2 does not resolve the poor thermodynamic properties of nuclear power.

Its really what the concept does. It recoups some of the heat value in the form of increasing the energy value of 2H2 by 50%.

An imagined combined cycle nuclear power plant with gas or liquid metal in a heat transfer loop supplying first process energy, then turbine energy with the residue heat from turbines preheating the Sabatier process...

Well, that would have insane efficiency
jergul
large member
Thu Jan 30 12:31:08
Using H20 in the turbines of course. The gas or liquid metal in a closed loop.
Turtle Crawler
Admin
Thu Jan 30 19:15:19
I don't think this works. Better off making electricity. The only way I could think of doing something like this is if you ran out of natural gas and for some reason people couldn't get heat pumps.

Neither is true though.

If the waste heat is high enough for reduction then you can still get lots of electricity out of it if you wanted to.

It's a nuclear reactor though, maybe they can just bump up the fuel usage instead of spending money to make it more efficient.

If you want to be crazy efficient with natural gas the answer is co generation at the point of use. Generating electricity in cases where you really wanted the heat, then you create as much electricity as you needed in order to get the heat you wanted. Expensive though.
jergul
large member
Thu Jan 30 21:12:19
TC
The discussion is specific to the UK where a cap and trade system will eventually make conventional natural gas prohibitively expensive.

It is not about using electric capacity. The inferred argument is that carbon neutral generation will at times produce far more electricity than is needed. That will be turned into H2.

What then to do with excess thermal produced at nuclear power plants? Waste it? Insane! Make fresh water? Rediculous!

Bump up the energy value of 2H2 by 50% to make synthetic natural gas suited for distribution in a pre-existing grid?

Reasonable!
jergul
large member
Thu Jan 30 21:15:19
The argument you were making is against H2, not against synthetic natural gas.
seb
Member
Fri Jan 31 01:27:33
Jergul:

I'm just not particularly clear what the point is.

The goal is to allow distribution of energy for domestic heating (boilers and cookers), and our theory is we can use waste heat from nuclear.

Although from core to turbine thermal efficiency is 33%, tertiary loop steam to turbine is around 60%. So the rest may not be that accessible as it must be lost somehow in the primary and secondary loops.

In which case you might be looking at 1GW electrical, 650MW of 200 degree steam and maybe 1350MW of hot water.

But let's say you do have 2GW of 200 degree or so steam to play with.

You can use that 2GW to make natural gas at some efficiency, plus use some amount of energy to get concentrated co2.

Or you can use that 2GW to make hydrogen by steam reforming natural gas and capturing the co2.

The latter is likely to be more efficient: it doesn't involve extracting and concentration of co2 and the binding energy of the inputs and outputs suggest it should take less energy to take methane and water to hydrogen and co2 than co2 and water to methane.

jergul
large member
Fri Jan 31 06:36:42
Seb
Maybe we should take a step back.

Assume conditions were intermittent surplus electricity production is being used to produce H2.

A simple energy balance suggests that to utilize half of available thermal (giving total plant efficiency of 67%) would still soak up more surplus electrical production than the powerplant alone can supply (2/3rds of the energy goes to hydrogen production).

This means that a nuclear power plant can both soak up surplus electricity production and boot-start direct demand for hydrogen.

The surplus production can be localized by taking nuclear power off grid production and using its capacity to make both H2 and CH4.

The steam process you are decribing generates heat (you are breaking down CH4 to 2H2). Its a legacy process that does not properely factor in cap and trade conscequences (ie what a silly way of turning fuel into food).

The point is still to use thermal from nuclear to lift up H2 to CH4 and distribute a 10% H2, 90% CH4 mix in the UK gas pipe network.

What I am actually trying to do is to save nuclear power in the UK. It needs something to boost its efficiency significantly. And not something rediculous like creating fresh water.

The industry needs to flip its perspective and consider itself primarily as a supplier of thermal energy. Its what a nuclear plant does after all.
jergul
large member
Fri Jan 31 07:07:47
I am not saying the timing is right for introduction now. But it is probably about right to start planning as nuclear power takes forever.

Those 7 points I mentioned last thread are still relevant.

1. Get reversable heat pumps deployed
2. Get electrical vehicles deployed
3. Get wind and solar deployed
4. Get that new interconnect to Norway

Level and stabilize the sinus curve.

(after 10 years - 75kwh battery packs degraded to say 50 kwh after refurbishment and placement in elstorage facility. 1 million battery packs = 50 gwh storage capacity. Jergulmath. Use any numbers you like).
Seb
Member
Fri Jan 31 16:44:29
jergul:

Again, why not just use the surplus electricity to generate H2, and the waste heat from nuclear to crack CH4, capture the CO2 centrally, and distribute the H2?

It is very likely to be more efficient overall - unless you have concentrated CO2 which is hard to come by without either cryogenic distillation or combustion.
jergul
large member
Fri Jan 31 19:13:20
Because the process that cracks CH4 produces heat. Thermal energy from nuclear power is redundant.

CH4 + O2 -> CO2 + 2H2 + 300 kj

You also have the problem of producing lots of H2 and CO2 and have nothing to do with it without huge investment. You are also buying CH4.

The direct chemical energy cost of fracking is 33%. Take 100% in CH4, be left with 67% 2H2 when done.

http://www...-important-to-humanitys-future
jergul
large member
Fri Jan 31 19:42:40
For what you are thinking of:

24H2O -> 24H2 + 12O2

12O2+C6H10O5 -> 6CO2 + 5H2O

So right idea, but use the other byproduct of electrolysis. You get concentrated CO2 for whatever purpose after a light purifying process (none of that pesky N2).
jergul
large member
Fri Jan 31 19:53:33
Sammy
TL:DR - The Sebatier reaction I am talking about can be used to colonize Mars!
Turtle Crawler
Admin
Fri Jan 31 23:08:15
It's a pretty cool plan then. You'd either need the machinery running 24/7 to hit the demand or leave it turned off when there is no free heat?
Seb
Member
Sat Feb 01 02:49:24
Jergul:
That's not the process in was thinking of.

https://en.m.wikipedia.org/wiki/Steam_reforming

CH4 + H20 <> CO + 3H2
CO + H2O <> CO2 + H2

9 X (by mass) CO2 produced for each unit of H2
jergul
large member
Sat Feb 01 03:43:09
TC
Assume that both electricity production and electricity consumption follow two seperate sinus curves for the grid as a whole.

Electricity production from the nuclear power plant would be diverted to cover gaps between supply and demand intermediately, so at times there would be no hydrogen production, but still production of CH4 from stored H2.

Stored where you ask? Well, as it turns out, the UK is currently decommissioning a 3 bcm storage system. H2 could be stored there (nothing wrong with the storage, but all the connecting stuff is being removed. H2 has more rigid tolerances than CH4, so the connecting system needs to be built from scratch anyway.

I am still assuming Smith's invisible hand is involved somehow with supplying various input stuff, but it would be a pretty cool industrial complex if you went Soviet style and placed everything on site (the external input would be water and plant based combustion material like wood chips or agricultural waste).

Here:

Bio powerplant
Uses O2 from electrolysis. Gives CO2, power, thermal.

Electrolysis facility
Uses water and power. Gives H2 and O2

Sebatier facility
Uses H2, CO2. Gives CH4, H2O(!), thermal (!!)

Nuclear facility
Uses $$$. Gives thermal, power.

======================

H2O(!), thermal(!!). Well fuck. That completely destroys the role of nuclear power in this.

The problem with the Sebatier reaction is dumping heat to bring operating temperatures down to optimum, not adding heat.

There is some net loss (1/3 of chemical energy) in conversion from H2 to CH4.

It is really hard to find something useful for nuclear power plants to do if not at insanely massive scales (the larger the scale, the more sense they make).

Ah well. Thoughts not explored and all that.

But it still does give carbon neutral CH4. I will revisit later.
jergul
large member
Sat Feb 01 03:51:02
Seb
The energy equation does not change. The process produces heat. Rendering nuclear thermal redundant.

So does the Sebatier reaction as it turns out.

You get the same effect by burning wood with pure O2. So still use the other byproduct of hydrogen production if you want concentrated CO2 (see above)

Its carbon neutral without CO2 sequestration.
jergul
large member
Sat Feb 01 03:57:34
Gah, strike that. You do need to add thermal.

Let me see...
jergul
large member
Sat Feb 01 04:16:30
...It does not contribute to solving what I was looking at and is not a good way of generating concentrated CO2 if we assume green energy will be making H2 and O2.

Carbon neutral without sequestration is better than carbon neutral with sequestration.

Seb
Member
Sat Feb 01 06:16:38
Sat Feb 01 06:02:26
It's better from a carbon perspective sure, I'm just not convinced it works economically: I suspect the relative system efficiencies would make steam reformation win out.

There is also a huge benefit in switching the gas infrastructure to pure H2 in that it will remove a huge amount of emissions by forcing a change away from combustion for domestic heat, and can be done without needing to find a primary energy source equivalent to that in the Ng.

So I think it might be an incredibly effective means of rapidly phasing out a huge slice of emissions. All gas would now be being burned centrally, facilitating capture.

That said, huge asterisk over long term storage I'll grant.
jergul
large member
Sat Feb 01 08:32:11
Seb
You do see the problem with a concept that requires building a H2 distribution network and a CO2 sequestration system simply for the product to be carbon neutral?

Never mind that the process demands extremely high quality steam at 900-1000 C.

The best way of getting that is by doing something incredibly stupid - take storable hydroelectricity.

Lets dispatch nuclear power for now.

Do you see the benefit of using O2 in combination with solid biofuel (woodchips or whatever) to produce energy and highly concentrated CO2?

The product is carbon neutral even without sequestration.

It has the added advantage of giving a byproduct of electrolysis a clear purpose at any scale.

The benchmark energy loss to avoid is 50%. That is the loss of shipping electricity to Norway so it can save its water resevoirs, then shipping it back when the UK is short on electricity and Norway lets hydro run wild.
jergul
large member
Sun Feb 02 04:27:17
Seb
If we want to crack, then natural gas from resevoirs is the wrong feedstock.

Cracking solid bio is simply better from a CO2 emission perspective.

Consider pyrolysis a form of cracking in this perspective (as it is technically just that).

Lurker explanation: Cracking requires heat input. I am still looking at what to do with termal energy from nuclear power.
Seb
Member
Sun Feb 02 04:37:04
Jergul:

The existing gas network can be converted to H2 in a relatively straightforward way.

Solid biomass needs much more processing. You can just turn it to biochar, or through fermentation, which I assume you'd be doing anyway in parallel.

The cost of brining all that solid mass to the nuclear power plant (normally sited in fairly remote places) isn't great either.

jergul
large member
Sun Feb 02 04:42:12
Pieces of puzzle
Nuclear
$$$$ -> Thermal, Power

Wind, Solar
$$ -> Power

Electrolysis
Power + H20 -> O2 + H2

Biofeedstock
Area + time + $ -> biofeedstock (ultimately a form of solar energy).

Pyrolysis
Bio feedstock + Thermal -> Biochar, CO, CH4++

Biochar
Biochar + O2 -> CO2(concentrated) + Thermal

Biochar - 75% carbon by weight. Can be directly sequestered in topsoil.

Sebatier
H2 + CO2 and/or + CO -> CH4
jergul
large member
Sun Feb 02 04:54:40
Seb
Do you have a cost estimate of converting to H2? That capital investment would be an important component in finding leveled costs of H2 supply.

If you want to decommission the natural gas net, then just do that. Tossing in replacing with H2 is a red herring from a rational perspective.

Excess electricity production can always just be exported to Norway for storage.

Producing biochar is trivially easy. Compared to say cracking CH4 at temperatures in excess of 900 C. Feedstock supply is trivially easy. Compared to say importing LNG from the USA.
jergul
large member
Sun Feb 02 04:58:25
Ultimately though, you are adding CO2 to a system while biochar is CO2 neutral.

If you assume CO2 will be neutral for your concept, then assume biochar will be CO2 negative by a similar margin.
Seb
Member
Sun Feb 02 10:02:22
Jergul: posted a link a while back on H2 conversion.

The challenge with biochar is moving bulk goods.
Its not a great source of power.

Natural gas still has benefits in that it's available, easily transported etc.

If we can capture the carbon (if) there's benefit.

Re the temps and pressures, one way to look at surplus wind power is you have surplus high grade stream at a nuclear power plant ;-).

But honestly I think we are trying to hard to find a rationale for nukes here.

You do all of the things. But conversion of the domestic gas network to operate on H2 would be a very powerful lever for decarbonisation. Quite how you do it, I'm not sure. Probably over a decade and developing a boiler/hob that can use both; coupled with regional roll out.
jergul
large member
Sun Feb 02 11:04:19
Seb
You are getting very close to just saying random stuff.

Fact: Biochar is a better source of power than coal. You know, the stuff you have been moving about since the 1740s.

The feedstuff to make it is bulkier, but not by orders of magnitude.

The main reason to think industrial production of biochar is better than cottage production (both are technically and economically feasible. Biochar scales well) is that the process gives gassification of methane (mainly).

We are trying too hard to find a rational for nukes. Surplus high grade steam only means 350 C with current designs.

Biochar production would increase current nuclear power plant design efficiency substationately.

Removing the natural gas network is the very powerful leverage for decarbonization. Introducing hydrogen cracked from natural gas would amount to recarbonization (at about 85 grams CO2 per kwh even assuming carbon capture and storage of cracked CO2 emissions).

Just go full electric if the alternative is cracked H2.

I suspect the only reason we are even discussing it is because the oil and gas industry is to some extent dictating the debate.

Absolutely any problem biochar feedstock has is duplicated in natural gas resevoirs. We are just used to giving the gas industry huge tax credits, pollution and emission exemptions to treat the mess that actually comes out of the well.
jergul
large member
Sun Feb 02 11:19:27
"You are getting very close to just saying random stuff."

Strike that. It was uncalled for and based on my misreading a paragraph that you wrote.
Seb
Member
Sun Feb 02 11:52:16
Jergul:

Show me a biochar field with the energy density of a coal mine!

It takes around 10 tonnes of wood for one tonne of biochar, so that's a lot of lugging wood around, and unlike a coal mine which facilitates conveyor belts and trains, you've got to lug over hundreds of square miles of forrest.

It's ok, but I'm not sure it's going to get you very very far on decarbonisation - or we would just all adopt that now!

Going full electric is a possibility too, but likely to be resisted (electricity is $$$ compared to gas, and culturally gas cooking is preferred, myself included). NG remains very cheap, so if you can strip out most carbon by "burning" it centrally and distriuting hydrogen that would seem a possible win (provided it remains compatible with lower than electricity prices) - and may also enable fuel cells and cogeneration of heat and power in domestic situations.

But I think the differences here are probably to small to easily determine best approach.
jergul
large member
Sun Feb 02 12:28:18
I am actually unsure of how to measure coal density per cubic meter of rock and water. But I am pretty sure it does not compare well with bio-feed.

Now perhaps if we were harvesting mushrooms from deep underground to use as feedstock, we might have a comparative basis.

4 tons for one ton. Assume normal seasoning, though the correct measure would be volume, not weight.

Assume industrial production of feedstock. Still, it has the advantage of being accessible above ground.

Its more a question of supplementing, then replacing drilled natural gas. Not all of it. Carbon neutral is a 67% reduction of emissions.

Natural gas with full carbon capture is not going to be cheap and it still will not be carbon neutral (88 g per kwh with ccs 350 g per kwh without ccs).

H2 also has crap density. In addition to it fucking up pipes.

Seb
Member
Sun Feb 02 12:42:18
Jergul:

Last report I saw, albeit some time ago, used something more like 10 - I'm assuming this depends heavily on drying and seasoning.

Most coal is now open cast mined no? If underground I'd just do insitu gasification.

H2 density and pipes issue are as I understand it solveable.

jergul
large member
Sun Feb 02 12:56:39
Seb
Open pit mining has horrifically poor coal density.

Of course it is solvable. You replace all pipes and increase pressure and/or dimensions in the system.
seb
Member
Mon Feb 03 00:54:04
Jergul:
Yes, but less vertical lifting, and at any point localists (so good for conveyor belts etc) and even the worst open cast mine will be better compared to a forest.

Re gas, you are over egging it. Increased pressure. Gas network is part way through a shift to polyethylene pipes which are suitable.

https://www.theengineer.co.uk/converting-the-gas-network-to-hydrogen/
jergul
large member
Mon Feb 03 01:36:51
Seb
Did you just say less vertical lifting for coal mining?

You are trivializing all the processing that goes into coal and natural gas to prepare it for transport.

The forest equivalent would be chipping trees on the stump. Tada! Conveyor belt ready.

Feel free to give your best estimate on the capital costs involved with cracking, css, and redimensioning the natural gas system.

Leeds needs 4 MRS it seems. So 350 nation-wide.

In an energy balance perspective, you taking a 45% hit in order to get concentrated CO2 to reduced emissions from 350 to 85 grams per kwh.

The 45% hit does not include the energy cost of transporting and sequestering CO2.

This infers a doubling of fuel costs even without considering capital investments and increased operating costs. So something in the region of 3-4 times the cost including CO2 sequestration.

This also gives the correct price for CO2 emissions as the Leeds experiment shows us the total costs of doing something to sequester CO2 at scale.

I am fine with Leeds doing that. It levels the playing field for green energy. Assuming market access under similar conditions to what any roll-out of cracked methane gets.
jergul
large member
Mon Feb 03 01:41:42
Combined cycle gas turbines with css and reversible heat pumps on the consumer side is far better.

You will be paying a premium for the cultural experience of gas cooking (the capital cost equation becomes far worse if people adapt to rising gas costs by actually installing heat pumps).
seb
Member
Mon Feb 03 02:02:46
Are you arguing there's more vertical lifting in open cast mining than deep shaft mining?
seb
Member
Mon Feb 03 02:09:36
Jergul:

Reversible heat pumps is a huge domestic investment!

Redimensioning the gas system may not be necessary. And in this scenario aren't we using the nuclear excess steam when the wind is strong and the nuclear turbines don't need to spin?

So the capex is pressure vessels and gas pipes.

CO2 sequestration is a cost yes. Though an idea I liked was to try and capture it in plant mass on site which in quite liked as it allows your switch to fully carbon neutral. In suspect that's too cute to work in practice.
jergul
large member
Mon Feb 03 02:33:16
Seb
Its not fully carbon neutral. Reduction is from 350 to 85.

Pipings, fittings, instrumentation, and storage. + consumer side adaptions.

Redimensioning will not be necessary if the full cost is passed on to the consumer. Demand will plummet and take care of that.

Using nuclear power for that is science fiction. You would need a new type of nuclear power plant to start off with. And the cost prohibitive. Making steam instead of electricity would still have to qualify for the minimum pricing per kwh.

Huge how? 100 pounds a year perhaps including depreciation. Far cheaper than the fuel subsidy you will have to pay out to those in need.

But it is fundamentally unfair to say that the public will bear the burden of one type of investment, the consumer the burder of another, then say that the other is impossible because it is too much of a burden on the consumer.

Better then to equalize how things are subsidised.
jergul
large member
Mon Feb 03 02:34:20
Also, you need to build 350+ cracking plants to role out nationally.
seb
Member
Mon Feb 03 02:48:06
You are just inventing cost centres now without checking!

The main network will have been fully shifted to hydrogen suited materials by 2030, and domestic piping is welded copper. So say target 15 years, that's plenty of time to roll out compliant units.
Cubic feet meters will work just as well.

What's your logic on 85g.

The point about nuclear plants is they produce high quality steam 24/7. It requires precisely zero change to anything in the nuclear island to divert that stream away from spinning a turbine to an industrial process as it's all conducted in the tertiary coolant loop.

At the moment we need to pay wind turbines to shut down if they are producing more electricity than the grid can absorb because it's not possible to stop nuclear plants, but if you can use that steam for something else other than spinning a turbine, that's a net win.
jergul
large member
Mon Feb 03 03:58:47
Seb
The cost estimate could just be found you know. Its 230 million pounds for the hydrogen transportation system alone. So 1000 pounds per household.

Natural gas drilling, production and transport is pretty CO2 intensive. I was citing numbers from some report or another.

Current UK designs do not supply steam of nearly high enough quality. You need 900-1000 C, not 350 C.

And you would still have to pay nuclear power their guarenteed price if it diverts steam from electricity to high quality steam.

Its a net win only if you think guarenteed nuclear electricity prices are the true baseline costs for electricity.

Leeds is not a bad idea. It can unleash green energy simply by creating a demand for hydrogen.

So expect lock out contracts where cracking plants get assured access.
jergul
large member
Mon Feb 03 04:04:06
I would fully support the measure if Leeds was required to use competative purchasing.

Dairy farmers would make money converting to hydrogen production and change the dairy tanker picking up milk twice a week to the hydrogen truck picking up hydrogen twice a week.

Thats how bad the economics look.

So yah, of course the contract will be lock in to keep pesky competition from competing.
jergul
large member
Mon Feb 03 04:15:33
What makes sense if for Leeds to convert to hydrogen capable, then let the market decide what mix of natural gas is distributed. From ~95% CH4 to 100% H2 depending on what is cheapest for the end user.

The mix would ultimately depend on how expensive CO2 emissions are.
Seb
Member
Mon Feb 03 08:27:08
Where are you getting your 350 from?

That looks suspiciously like the coolant intake temperature to the core, not the outlet.
Seb
Member
Mon Feb 03 08:33:29
Primary coolant outlet temp is in the high 600s, so only minimal compression needed.
jergul
large member
Mon Feb 03 09:04:07
350@15MPa, though actually 327@15,5MPa now that I checked.

http://ini...re/_Public/37/086/37086871.pdf



Seb
Member
Mon Feb 03 14:32:25
Jergul:

That's an EPR, of which we operate none. Our current fleet are AGRs. I think SMRs, though PWRs, don't have the same parameters as an EPR.
Seb
Member
Mon Feb 03 14:35:31
The rolls Royce offering is a similar high 300 degrees.

So yes, would need compressors.
jergul
large member
Mon Feb 03 16:58:07
Seb
Using compressors would remove using nuclear energy from the equation. Exit heat and pressure would be in the 300 range at 15 atmospheres.
Seb
Member
Tue Feb 04 01:08:39
Jergul:

Again, using pwr parameters.

Are we talking about new reactors or existing ones?

Getting the right combination of pressure and temperature is more complex from a pwr but you can just run a new coolant loop through which bills water, reduces pressure, passes the lower pressure steam back through a head exchanger and then compresses it. It isn't that complicated. The fundamental point is: you don't have to make Electricity if you don't want to now.
jergul
large member
Tue Feb 04 02:06:06
"The fundamental point is: you don't have to make Electricity if you don't want to now."

Then you have to increase the price of steam to whatever the nuclear power plant would otherwise have been getting if it had produced power.

GBP 92.50 per MWh

Cracking is getting mighty expensive.

jergul
large member
Tue Feb 04 02:08:52
lol, assuming that is the only cost beyond natural gas and taking the energy hit for conversion to H2...

3 p kwh becomes
14 p per kwh.
Seb
Member
Tue Feb 04 02:17:58
Jergul:

Why 14p? You are pricing this power as though it isn't surplus to requirements. I'm suggesting we do this during the periods where nuclear plants are effectively paying a subsidy to wind via the grid to not generate more Electricity than the grid can handle.
Seb
Member
Tue Feb 04 02:51:13
"GBP 92.50 per MWh"

This is the strike price for the first EPR. It isn't what the existing fleet are getting, and it isn't what the SMRs are priced at.

No, no, I'm absolutely not suggesting we build EPRs to crack natural gas. I've explicitly stated we shouldn't be building them at all (not that their manufacturers are that keen to do so anyway). In any case they couldn't be built in time anyway.

So I'm confused as to why you are benchmarking to EPRs.

Surely the point here is to sweat existing assets to achieve rapid decarbonisation.

In any case, the excess power produced overall during peaks is a cost - someone has to pay someone to stop generating power - so even using the price the electricity would sell for isn't the right metric.
jergul
large member
Tue Feb 04 02:56:44
I am pricing this power at the strike price nuclear power plants have negotiated for all electrical power they are able to produce.

They are not going to take a price cut just because you want them to produce steam instead of electricity.

Nuclear power aint subisidising shit. Paying windpower for their losses for not producing is actually a subsidy of nuclear power.

That will remain true for as long as nuclear power has contracts that assure them that all electricity they can produce will be bought at strike prices far higher than what competative generation provides.
jergul
large member
Tue Feb 04 03:01:20
"Surely the point here is to sweat existing assets to achieve rapid decarbonisation."

Is why I am benchmarking EPR.
jergul
large member
Tue Feb 04 03:03:29
Rolls Royce SMRs are the wrong technology for steam production anyway. You would want systems that use gas or liquid metal @900-1000 C.
jergul
large member
Tue Feb 04 03:07:55
Biochar is now technology for carbon sequestration if rapid is the key element.

We know the energy loss. 33% is lost by opting to store carbon in solid form instead of burning it.

And this is not a carbon neutral process. It is a carbon sink.
jergul
large member
Tue Feb 04 03:12:47
Consensus is that 15% of human emissions can be captured in biochar with business as usual practices in agriculture (no signficiant diversion of agricultural land).

On its own, without other measures, it increases global sink capacity from 35 to 50% of CO2 equivalent emissions.
jergul
large member
Tue Feb 04 04:23:00
8. Domestic insulation
9. Solar heating (has far better efficiency that solar power).

Turns out that domestic energy use is far higher in the UK per m2 than in Norway. Simple insulation to Norwegian standards would reduce energy use by 20%.

We are not that good at energy efficiency either because electricity is very cheap. So its a low bar to pass.
jergul
large member
Tue Feb 04 04:25:26
"Surely the point here is to sweat existing assets to achieve rapid decarbonisation."

Start off with the boring stuff in other words. Lower consumption by improving end-user efficiency.

Motivate by taxing end use carbon at higher rates on the one side, and subsidizing energy efficiency measures on the other.
Seb
Member
Tue Feb 04 05:04:59
Jergul:

How does it make sense to benchmark against operational and financial performance of a plant design that isn't operational anywhere in Europe, and isn't now likely to be built at all even looking at schemes sweating existing assets?

The existing assets in the UK context are advanced gas reactors.
Seb
Member
Tue Feb 04 05:59:14
"Start off with the boring stuff in other words. Lower consumption by improving end-user efficiency.

Motivate by taxing end use carbon at higher rates on the one side, and subsidizing energy efficiency measures on the other. "

Largely been done.

http://www...y-reveals-new-hydrogen-boiler/
Seb
Member
Tue Feb 04 06:05:38
Jergul:

"Paying windpower for their losses for not producing is actually a subsidy of nuclear power."

Either way from the plants it appears as a cost, so the value of producing gas is the payment they'd make to wind plus whatever they can sell hydrogen for (or rather, whatever gas wholesalers need to pay to get their gas cracked, so the cost of the gas they'd need to burn).

For the old AGRs, which don't have strike prices, this isn't 14p/kwh
jergul
large member
Tue Feb 04 06:31:00
Seb
Not likely to be built at all is far more of an "existing asset" than advance gas reactors in the UK. Which are not even in the preplanning stage.

But feel free to give me a different, realistic, strike cost for nuclear power. I will happily show insane pricing on fracked natural gas for that too.

If it had "largely been done" then you would largely have energy efficient energy used domestically. You are not even close.



jergul
large member
Tue Feb 04 06:42:04
We know what hydrogen can be sold for. Consumers pay 3 pence per kwh.

So nuclear power is saving 12 pence it does not need to pay wind generation and is getting in another 3 pence for hydrogen. Making a pretty profit of 8 pence per kw, instead of the 94 pence in strike prices. Well, you need to add on a few pence for buying ng to crack, and another penny or so for treatment and sequestration. So maybe 3-4 pence per kw hour instead of 94?

Sounds like a winner!
Seb
Member
Tue Feb 04 09:06:48
Jergul, AGRs are the generation of reactors we built in the 80s and the backbone of our current fleet.
Seb
Member
Tue Feb 04 09:07:59
Jesus mate... Google is your friend. I'm talking about sweating existing assets, you might want to have checked that you hadn't got the wrong end of the stick!
Seb
Member
Tue Feb 04 09:18:01
"If it had "largely been done" then you would largely have energy efficient energy used domestically. You are not even close."

You are assuming any measure will be %100 effective.

Energy efficient boilers etc have already been pushed heavily, along with smart metres. Schemes like the green deal etc.

The biggest source of energy inefficiency is actually poor insulation - to the extent customers will add double glazing and insulation to existing properties, it's been done as much as it will get done.

jergul
large member
Tue Feb 04 10:24:40
Seb
What is the strike price for AGRs (I obviously know what reactors your fleet currently is)? Since google is your friend, try quoting lower strike prices instead of waving your hand.

Your homes are 20% less efficient than ours. This is without my calculating for more adverse weather conditions here.

The two measures that would have best effect is better insulation (triple glaze is the actual gold standard these days) and mass deployment of reversible heatpumps.

The problem with your line of thinking is that you want to take the most expensive way of making high valued energy to make a lower valued energy source that retails at a fraction of the price of electricity.

The numbers will of course be attrocious.
Seb
Member
Tue Feb 04 10:53:27
Jergul:

There's no strike price. Because they pre-exist the grid and utility privatisation and were themselves privatised assets, the govt never needed to agree gauranteed revenue to fund them. To the extent they were uneconomic, the quote down will have been on BNFLs value on privatisation or sale to EDF. They compete for contacts to supply the grid as other plants do.

If you know these exist, why did you rather strangely say that they weren't even in pre-planning stage? I'm really not following you here at all.

"Your homes are 20% less efficient than ours."
Yes. But that's because a large chunk of our housing stock are Victorian or Georgian period architecture, and people will not take the hit on the house price by whacking on ugly looking external cladding obscuring lovely coving, window sills etc. Nor will they replace all the lovely stripped pine floors.

Short of draconian measures which nobody will support or demolishing and replacing housing stock, we've run out of accessible measures.

Efficiency on new build etc will increase, but we've pretty much hit the limit on what people will do on older stock while people are willing to pay a premium for poorly insulated houses.

Seb
Member
Tue Feb 04 11:04:50
"expensive way of making high valued energy to make a lower valued energy source that retails at a fraction of the price of electricity"

I think you are still ignoring the fact that at the time I'm proposing to use it, it's negatively valued - and the way I'm proposing to use it is vastly more efficient than electrolysis or the methane reforming.

Re heat pumps, they are much more expensive than gas, and not nearly as good for quickly heating a house or water. Air source heat pump has a coefficient of about 3-3.5 in typical UK climate, so still more than gas. Compared to an A rated gas boiler, you are looking at increases in operating costs even with current incentives. You'll need a newc electric hob.

And ground source is difficult to install in terraced housing where there's often no access to the garden, and you'd need to dig it up.

So there's limited take up.
jergul
large member
Tue Feb 04 13:14:09
Seb
Air-to-air. Its always a supplement to other heating. Stipulate a reduction of CO2 emmissions to 35%.

Also, feel free to stipulate that the full cost of CO2 emissions will be factored into the price.

At the time you are proposing to use it, green energy is still far cheaper than nuclear. The competition that might have to shut down production are gas-turbines. They at least have input factors that cost money.

I don't see how you would structure this anyway. A nuclear power plant will offer steam sometimes to a cracking facility when electricity is cheap, then have it run on electricity when electricity is expensive?

Nuclear power plants need to make serious money all the time. We know what the leveled cost of nuclear energy is.

How does steam cover that cost?
jergul
large member
Tue Feb 04 13:23:45
In sum: Export surplus electricity to Norway and take the 25% transmission loss.

Its better than the 35% loss you get from chemically degrading CH4 off the bat, not to mention the rediculously extreme difference between the price of a kwh electricity to that of a kwh natural gas.
Seb
Member
Tue Feb 04 13:35:58
Jergul:

No. Have it run on gas when electricity is expensive. Obviously. We are capturing the co2

AGRs electricity just gets cheaper anyway, until further life extension is ruled out. Like the old French reactors.

Seb
Member
Tue Feb 04 13:36:50
This is studf to do out to mid to late 30's.

Seb
Member
Tue Feb 04 13:39:30
The more renewables you add, the more you get periods of oversupply.

It's just a way of sweating an asset that you'd otherwise have to shut down at some point because it can't be turned off but needs to be.

Of course that also depends on whether we find better/cheaper energy storage options.
jergul
large member
Tue Feb 04 14:00:32
Nice hand wave there. Its one thing to capture concentrated CO2 from a chemical process.

Its another, distinct and separate process to capture it from combustion exhaust.

Use second hand lithium packs for storage. Or store it in Norwegian resevoirs.
jergul
large member
Wed Feb 05 01:29:17
Offshore wind posted huge profits.

http://e24...orbritannia-gaar-saa-det-suser

The subsidy levels may have been a bit excessive.

Generated enough electricity for 5 million housholds.

Revenue 450 million pounds. Profits 175 million.
Seb
Member
Wed Feb 05 02:17:32
Jergul:

I don't think mass battery storage is going to be scaled by 2035 for industrial power. Not if electric cars are expanding healthily.

So on a day when it's really windy, why will Norway be buying? Surely all your offshore North sea turbines will be going like clappers too.

Um, using gas to heat the stream for steam reformation is combustion.

The chemical process is steam reforming, separatingg the H2 is relatively easy given the relative densities of co2 and h2.

Yes, ultimately all of this will be more expensive than just burning natural gas in homes; but there's a preference for using gas. If people will happily spend thousands of pounds a year through a combination of not insulating and not replacing Windows even when offered subsidies; presumably they'd pay a premium for H2 over going electric.
jergul
large member
Wed Feb 05 03:08:38
Seb
Electric cars need to expand healthily (like say in Norway). They are the key source of batteries for stationary storage. Battery packs lose energy density over time. They can be refurbished to regain some of the loss, but should be retired from transportation at about the half-life of they vehicles they are powering.

This would be your source of batteries for storage.

I am retyping stuff now from earlier threads. Electric vehicles are key to flattening the sinus curve of electric demand.

Norway still gets 95% of its electrical supply from hydro. When surplus in UK, buy it. Crank shut valve on hydroplant to stop use of resevoir water.

Uhm, yes. Using gas to heat stream is a combustion process that contains tons of nitrogen. A complete different process for CO2 capture is required in addition to the one you are imagining for cracked natural gas.

Your idea is to force them to go over to hydrogen, no? I don't think very many would opt to do so if natural gas is available at a significantly cheaper price.

That new NPP was offered subsidies, but clearly not enough of them. I suspect you have the same trouble with humans.

But as a low threshold measure, you should upgrade homes for the elderly instead of paying for their fuel.

The problems seem to me to relate mostly to a combination of crony capitalism + politicians liking to put their stamp on prestigous projects instead of mundane practical ones.
jergul
large member
Wed Feb 05 03:11:52
Tons was the wrong measure. Km3 of nitrogen gas.
jergul
large member
Wed Feb 05 03:15:18
Assuming stockimetric combustion - 6 parts nitrogen for 1 part CO2 and 1 part water.
Seb
Member
Wed Feb 05 04:56:08
There will be nowhere near enough reconditioned batteries in the mid 30s though.

"Your idea is to force them to go over to hydrogen, no? I don't think very many would opt to do so if natural gas is available at a significantly cheaper price."

It won't be though. That's the point about converting the network. Getting retail adoption of heat pumps has failed, getting further insulation has hit the buffers. Preperences in some segments are too strong. Hydroginsation is a very strong lever for decarbonisation. It can be done by fiat with far less pushback than say, simply shutting down the infrastructure. Plus it allows options for co generation fuel cells etc. which gives resilience, backup and a potential alternative to Li batteries for cars if needed. But these are all rando engineering options. Mainly, it's attractive for the relative political ease of rapid decarbonisation. I just don't see production of carbon neutral natural gas at scale and cost to decarbonise domestic Ng use by say 2035. Which you need to.

Much of the energy for carbon sequestration is in cooling and compressing the gas, which gives you separation from nitrogen. So that's baked in. Plus cryodystilation of air for getting gases is an existing industry which could be colocated to get better overall efficiency.

"But as a low threshold measure, you should upgrade homes for the elderly instead of paying for their fuel."

Mostly, the elderly end up in efficient new build when they downsize; but where they don't the last thing they want to do is knock 20% of the value of their house. Cf. "Death tax" and May's disastrous election pitch.

Uptake of energy efficiency isn't about how much you can reduce the cost of investment. You'd actually need to pay people a lot of money on top to compensate them for the loss of value of their houses. Tl;Dr it makes them look ugly.

jergul
large member
Wed Feb 05 05:31:27
Climate control improves the value of a home. Again, as a supplement to natural gas.

1.8 million council households then. Lets call that the low threshold measure.

Cooling-compressing-cooling-compressing is energy demanding. So you want to to it for both the crack and the combustion emissions now?

Luckily, Leeds is going to the forefront, so we will get data on how hideously expensive this will be. Leeds is, what, 1.5% of UK households?

And yepp, you would be forcing people to convert to H2.

Depends. You will not have enough used lithium batteries domestically because you are doing everything back-assed backwards. But there is always the international market. Norway does not actually need 2nd hand batteries for storage because of hydro. We will start retiring battery packs at scale in 5-7 years. I rather expect your wind producers may start snapping those up. When I say your, I think I mean our. At least off-shore :).
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