Liquid air battery?

[Pugglt Auld Jock]

This just came up on my computer's news alerts. I've never heard of this before and got a bit excited thinking it was an actual battery. But no, what they are doing is using surplus green energy electricity to compress air 'till it's liquid and temporarily storing it. then when extra is needed by the grid they use the stored pressure to power a turbine which creates the electricity. Ingenious I suppose but we've been doing it for years up here with hydro by using excess electricity to lift water to elevated reservoirs in the mountains and then releasing it when heavy load comes on, then pumping it back up again during slack periods.

Can't help wondering how much energy is lost each time in the pumping process?

 

[DaveMcT]

It's not just the pumping, it's also the power turbine at the delivery end. Quote from https://www.thegreenage.co.uk/tech/liquid-air-storage/

According to the Institute for Mechanical Engineers (IMechE), the process is anywhere between 25% and 70% efficient.
​

70% of the input energy "could" be recovered. But just as likely only 25% recovered, meaning 75% would be lost. Reality will be somewhere in the middle but basic physics is against it.

Check out Moltex Energy for what we should be doing. Use up the high level waste nuclear fuel created by existing nuke plants. That resolves the ultra long term storage issue without mining any new fuel. Old used nuclear fuel has 95% of its energy remaining, so the Moltex can deliver at least 20x more energy output for the same weight of fuel used. Currently stored high level nuke waste has a half life of 30,000 years. Waste from Moltex reactors will have a 1/2 life of 30 years. They can burn all the nasty "transuranics" that "normal" reactors can't work with.

 

[AndyRKett]

This just came up on my computer's news alerts. I've never heard of this before and got a bit excited thinking it was an actual battery. But no, what they are doing is using surplus green energy electricity to compress air 'till it's liquid and temporarily storing it. then when extra is needed by the grid they use the stored pressure to power a turbine which creates the electricity. Ingenious I suppose but we've been doing it for years up here with hydro by using excess electricity to lift water to elevated reservoirs in the mountains and then releasing it when heavy load comes on, then pumping it back up again during slack periods.

It seems to be a more primitive form of putting unused energy in a battery. I suppose the stored Potential/kinetic energy could be massive compared if you have lots of very big cylinders, and those cylinders are going to be massively cheaper than an equivalent sized battery. But its just biding time till battery technology is massively cheaper as then you'll just put the excess energy directly into a battery for later.

Or as I'm sure one island does in Scotland use the extra power to break hydrogen from water, then use that hydrogen to power their local ferry.

That said I'm sure Denmark already has a Battery powered Ferry so again there are minimal losses where batteries are used compared to turning the power into something else so conserve it.

Check out Moltex Energy for what we should be doing. Use up the high level waste nuclear fuel created by existing nuke plants. That resolves the ultra long term storage issue without mining any new fuel. Old used nuclear fuel has 95% of its energy remaining, so the Moltex can deliver at least 20x more energy output for the same weight of fuel used. Currently stored high level nuke waste has a half life of 30,000 years. Waste from Moltex reactors will have a 1/2 life of 30 years. They can burn all the nasty "transuranics" that "normal" reactors can't work with.

Doesn't work Doesn't work Doesn't work Doesn't work Doesn't work Doesn't work Doesn't work

I've looked into this loads and there is so much that has not been worked out, There is so much in what you say which just isn't true. The salts in this design of reactor cause massive corrosion problems, which there is currently not a metal that will overcome.
Basically if the pipework becomes holed by corrosion the whole system dumps liquid nuclear waste everywhere, completely destroying the reactor. If the reactor gets to cold you brick the reactor. You also can't use waste you need a very specific fuel source to power them and you have to constantly remove buildups of contaminants caused by the reaction process to not poison the reactor, so they 're not hugely efficient in terms of waste they actually produce a lot of waste.

 

[DaveMcT]

I've looked into this loads and there is so much that has not been worked out, There is so much in what you say which just isn't true. The salts in this design of reactor cause massive corrosion problems, which there is currently not a metal that will overcome.
Basically if the pipework becomes holed by corrosion the whole system dumps liquid nuclear waste everywhere, completely destroying the reactor. If the reactor gets to cold you brick the reactor. You also can't use waste you need a very specific fuel source to power them and you have to constantly remove buildups of contaminants caused by the reaction process to not poison the reactor, so they 're not hugely efficient in terms of waste they actually produce a lot of waste.

In the case of a Weinburg MSRE (and all of the US salt designs) there are serious regulatory problems. The lithium salts create tritium and the lithium gets plated onto heat exchangers, flouride salts etch metals, etc, etc. Pumping ferociously radioactive liquid is asking for trouble. Salt plugs, dump tanks, pipes, heaters, etc are a radioactive nightmare. Getting a fraction of that safety certified is pretty much impossible.

Moltex from the outset looked to keep it entirely passive. They removes all active safety systems bypassing all those design/regulatory issues. The reactor casing is not a pressure vessel. It operates at slightly under ambient pressure.

Fuel salt is contained in 10mm zirconium plated stainless tubes. The only difference from traditional oxide fuels is the fuel is liquid in use. There is no fuel pumping because that would never get safety certified.

It's fast spectrum so there is no moderator = no carbon core to distort and require replacement.

The salt tank moves heat from the fuel rods entirely by convection. This chloride salt has no fuel so is not radioactive and being an ionic compound cannot become radioactive. A leak in the tank would not pass radioactivity into the reactor building.

There are no pumps in the reactor. Cooling, even at full load, is entirely passive. and it has a highly negative temperature coefficient. It will not over-heat, even with all external cooling stopped. It gets hotter (of course) but the power level drops rapidly. Passive air cooling around the casing keeps it safe until the control rods drop or the fuel runs out.

The salts are kept reducing so there is no corrosion. There is no lithium salt so plating heat exchange surfaces is not an issue.
Heat is extracted by a third salt via a heat exchanger. This is pumped but well proven "solar salt" used in plants like Andasol in Spain. This is a mixture of NaNO3 and KNO3, used to heat thermal stores as they do at Andasol. This heat transfer circuit is outside the nuclear island so does not come under nuclear regulations.

The problems have been proving that iodine and caesium cannot escape from the fuel. That's been proved with non nuclear physical models. These reactive elements form salts so do not escape as gasses as they can in solid fuelled systems. Xenon removal was proved in similar ways.

Moltex expect to be online by 2028 with people like Atkins independently overseeing the designs. Babcock are lined up to make these commercially.

 

[chris3234]

In the case of a Weinburg MSRE (and all of the US salt designs) there are serious regulatory problems. The lithium salts create tritium and the lithium gets plated onto heat exchangers, flouride salts etch metals, etc, etc. Pumping ferociously radioactive liquid is asking for trouble. Salt plugs, dump tanks, pipes, heaters, etc are a radioactive nightmare. Getting a fraction of that safety certified is pretty much impossible.

Moltex from the outset looked to keep it entirely passive. They removes all active safety systems bypassing all those design/regulatory issues. The reactor casing is not a pressure vessel. It operates at slightly under ambient pressure.

Fuel salt is contained in 10mm zirconium plated stainless tubes. The only difference from traditional oxide fuels is the fuel is liquid in use. There is no fuel pumping because that would never get safety certified.

It's fast spectrum so there is no moderator = no carbon core to distort and require replacement.

The salt tank moves heat from the fuel rods entirely by convection. This chloride salt has no fuel so is not radioactive and being an ionic compound cannot become radioactive. A leak in the tank would not pass radioactivity into the reactor building.

There are no pumps in the reactor. Cooling, even at full load, is entirely passive. and it has a highly negative temperature coefficient. It will not over-heat, even with all external cooling stopped. It gets hotter (of course) but the power level drops rapidly. Passive air cooling around the casing keeps it safe until the control rods drop or the fuel runs out.

The salts are kept reducing so there is no corrosion. There is no lithium salt so plating heat exchange surfaces is not an issue.
Heat is extracted by a third salt via a heat exchanger. This is pumped but well proven "solar salt" used in plants like Andasol in Spain. This is a mixture of NaNO3 and KNO3, used to heat thermal stores as they do at Andasol. This heat transfer circuit is outside the nuclear island so does not come under nuclear regulations.

The problems have been proving that iodine and caesium cannot escape from the fuel. That's been proved with non nuclear physical models. These reactive elements form salts so do not escape as gasses as they can in solid fuelled systems. Xenon removal was proved in similar ways.

Moltex expect to be online by 2028 with people like Atkins independently overseeing the designs. Babcock are lined up to make these commercially.

I hope it works out but frankly it seems to be another nuclear fusion with that its allways 10 years away from commercial use

 

[varesecrazy]

I hope it works out but frankly it seems to be another nuclear fusion with that its allways 10 years away from commercial use

Yes

The 'tokomak' kit down here seems to be getting another push ( more funds..)

 

[AndyRKett]

Fuel salt is contained in 10mm zirconium plated stainless tubes. The only difference from traditional oxide fuels is the fuel is liquid in use. There is no fuel pumping because that would never get safety certified.

I didn't say fuel , i said nuclear waste. The salt will take up radiation and that is being moved through the system. If the salt leaks that is still a significant leakage of nuclear waste.

The fuel rods contain valves in the top to release radioactive gasses.

As I stated before if they have to shut down the reaction in an emergency and the salts solidify around the core then there no easy way to recommission the plant, and its basically lost.

Motex as a company get a few quid bungged their way every few years, I think recently they have been given £3.5M to do some further research but they do not have the money or means to build any sort of power plant or experimental reactor and as such there is no way in the foreseeable future that anything will be built by they, they simply don't have the means.

 

[DaveMcT]

I didn't say fuel , i said nuclear waste. The salt will take up radiation and that is being moved through the system. If the salt leaks that is still a significant leakage of nuclear waste.

The fuel rods contain valves in the top to release radioactive gasses.

As I stated before if they have to shut down the reaction in an emergency and the salts solidify around the core then there no easy way to recommission the plant, and its basically lost.

Motex as a company get a few quid bunged their way every few years, I think recently they have been given £3.5M to do some further research but they do not have the money or means to build any sort of power plant or experimental reactor and as such there is no way in the foreseeable future that anything will be built by they, they simply don't have the means.

If anyone today rocked up with a pressurised water design, they'd be laughed off the premises. These systems have safety hazards at every turn and they only use 3% or 4% fuel energy so used fuel waste is big issue.

Moltex is partnered by New Brusnwick Power to build a fast spectrum nuke reactor, which will burn down their irradiated fuel stockpile and be online by 2030. Moltex will not own the plant.

The whole point is the Moltex reactor tank is heat transfer salt only. IT IS NOT FUEL so any leak would not be radioactive. Salts being ionic compounds cannot become radioactive unless active elements are added to the mix. But to keep the nuclear areas legally and regulatory separate, the heat is removed by a third salt loop using systems identical to those used in solar thermal power plants. There is no dump tank but the heat transfer salt would be removable if it needed to be.

The fuel salt is contained in tubes operating at ambient pressure. The heat is moved by convection circulation. Just like any reactor the fuel never mixes with the heat transfer fluid.

The Weinburg MSR design at Oak Ridge Labs clocked 13000 hours at full load between 1965 and 1969. Nixon closed it down because he wanted Westinghouse (from his home state) to corner the markets with its PWR. The MSR would not happen today simply because the regulatory process would take decades. However, in terms of safety there is far more potential for problems in PWRs. These are mitigated with complex engineered systems at enormous cost. We only have them today because the regulatory demands have already been set to suit them.

Incidentally, Alvin Weinburg (who held PWR patents) always said the PWR was perfect for ships and submarines because of it's small size and always has a huge passive cooling water supply. But he also said up-scaling PWRs to utility plant sizes would cause significant safety problems. A few years later the, Westinghouse reactor at TMI proved him right.

PS the only reason the Moltex reactor could be "lost" would be if the fuel was left in-situ to burn out over the following few years. Ultimately it would cool and go solid but it could potentially be boxed up and left to cool. Try that with a PWR and see what happens. The fuel rods are there to be fitted, shuffled and removed during refueling. The heat transfer salt can be heated and drained or simply drained while it's hot. It wont be radioactive, because salts are ionic compounds which are not affected by ionising radiation.

 

[AndyRKett]

It wont be radioactive, because salts are ionic compounds which are not affected by ionising radiation.

Literally everything is already radioactive including salts. Potassium chloride is famously radioactive, but any other salt compound exhibits varying degrees of radiation. Bombard anything including salts with radiation and you will convert them to radioactive isotopes of the same elements.

My understanding is these salt reactors would use fluorine salts, fluorine has over a dozen different isotopes most of which are unstable and therefore radioactive. Bombard a stable isotope of fluorine with free neutrons like what you have in the core of a reactor and you get radioactive isotopes of fluorine.... bombard any element in the core of a reactor and you get radioactive isotopes of that element. Not only that but fusion reactions break elements down into other radioactive elements such as tritium and helium being produced by fission of lithium-6 hit a non radioactive element of lithium(6) with neutrons in a reactor and you get radioactive elements of hydrogen.

This is all high school A-Level stuff. Which is why when you go on and on about salt reactors, it’s obvious you don’t really know the science and you’re just buying into the marketing that companies spew in order to get funding

 

[DaveMcT]

You are such an abrasive &^(&^%

So I'm wrong about a small issue Boo Hoo. The primary coolant salt becoming slightly radioactive is a trivial issue. Its sat at ambient pressure in a sealed steel vessel wrapped in a metre of concrete shielding. Compared to the problems and hazards and costs of wrapping nuclear fuel with high temperature, high pressure water. Not to mention fuel rods that become so internally stressed they can only take a 4% fuel burn-up. And the need to store them in deep water cooling ponds for who knows how long.

Moltex are using chloride salts exactly because lithium flourides are so damaging and they produce tritium. The salts used in their power take-off circuit are the same stuff used in solar plants. Well understood and well proven. They do not corrode the pipes internally and they do not become radioactive. It's already been agreed by the regulators that the tertiary circuit is outside the nuclear regulated zone.

We can agree to differ (unlikely) but when Moltex get it online before 2030 I hope you appreciate that things can be done when people look for reasons to get them done. 2030 is in the Moltex contract with New Bruswick Power so they'd better get it done.

 

[AndyRKett]

but when Moltex get it online before 2030 I hope you appreciate that things can be done when people look for reasons to get them done.

In 2010 the UK produced just 6.5% of its energy from renewable resources, 10 years later and we're producing 37% of our power from renewables. Battery tech is improving and becoming cheaper year by year, We are already building a massive new nuclear powerstation at hinkley point. another 10 years from now, they may have a working reactor in canada, but it will still only be experimental, and they will need to refine and improve the technology before it can be rolled out to be a viable source of power generation, that could be another 10 or even 20 years. Then the UK would have to commission and build its own plants which would require a complete overhaul in UK nuclear regulations. Feesably you could easily argue that we are still 30+ years away from these reactors if they were ever overcome technological and bureaucratic hurdles, by which time I can't see any developed country wanting to build new nuclear power stations. The energy world will be a very different place by then and nuclear power will be looked on in much the same way as Coal is now.

You can argue all you like about how clean MSR is but it will still produce nuclear waste in the form of gas, fuel waste and the salt and reactor vessel will also become highly radioactive over the course of their use.

You are such an abrasive &^(&^%

Jock started a post about something he found interesting and for the umpteenth time you tried to derail a topic to talking about Moltex salt reactors, which while it maybe interesting, you clearly don’t understand it and it has nothing to do with the original topic.

If you want to talk about something controversial like this you’d better be prepared for people not to agree with you. If you keep quoting me or following up my posts so I’m gonna reply. Rather than hark on about nuclear reactors why not try joining in the conversation about liquid air batteries.... you know the think this thread was actually about?

 

[varesecrazy]

Liquefying gasses uses massive amounts of energy..


And pricey kit..

This is probably another case of 'because we can..'

Rather than 'because its right'


I used to be involved with Helium recovery.

Helium : a finite resourse..


This time last year 'Air' wasnt classified as such..

 

[DaveMcT]

This would make batteries of any type redundant. It's molten salt so OMG here we go again. It could be base load but just as easily a peaker plant alongside renewables. All done with fuel you have been paid serious money to take away.
https://www.youtube.com/watch?v=aHsljVnY6oI

The core is totally self regulating and will drive zero or 10MW just as easily as 1000MW. The power from renewables can fluctuate as they do but the plant will happily fill in the gaps to meet demand.

Every Kg of nuke fuel has only had 1/25 of its energy removed. The other 24/25 is waiting for someone to exploit. If you only use the old used nuke fuel to power your new plants, you would have power for hundreds of years and never need to mine any new uranium or thorium for that matter.

The point is they would burn down the ultra long life nuke waste which (regardless of what anyone says) is a huge cost and there is no disposal solution. The 1/2 life is 30,000 years. When burnt down in an Elysium or Moltex its remaining 1/2 life is 30 years.

The designer Ed Pheil has thirty years nuclear engineering experience with the US Navy so he knows a thing or two.
They use chloride salts which are much less corrosive than high pressure hot water used in PWRs. He explains why at 1:22.

The engineering is done but they won't happen in USA because their regulatory process will not support anything which is not a PWR.