How Compressed Air Batteries are FINALLY Here

[@UndecidedMF]

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[@kevinleebailey]

No heat or oil problem.

[@Bob-yl9pm]

Lithium is ok for any light-weight portable storage, but an expensive (and hazardous) stationary bulk storage system, where the weight dosent matter!

[@TrueHelpTV]

I've been watching for years... not sure how I wasn't subscribed

[@UndecidedMF]

@@JOHNDANIEL1 that’s pretty clever.

[@TrueHelpTV]

@@JOHNDANIEL1 help me translate that into something I can understand. What effective "work" can you do with that. Are we talking a light bulb for a few minutes, or perhaps just enough juice for an emergency phone call or what?

[@MzM731]

I met a construction worker in the 80s who built his own windmill using a 260 gallon fuel tank to make curved blades, mounted on a truck rear end, that was only 30 ft in the air, turned in low wind & ran a generator. it generated more electricity than he needed so he compressed air into big propane tanks (which he buried in his yard). At the time he was puzzling over an more efficient way to run the compressor backward for generating electricity from the compressed air... I did a patent search for him but to his surprise it was not a new idea at the time. I'm sure he has passed away by now, he lived in central MN somewhere

[@yoghrut]

sounds like an engineer at heart

[@Garage_Chronicles_with_Mack]

@@MzM731 I'm in central MN. Do you know where about?

[@MzM731]

@@Garage_Chronicles_with_Mack maybe Wadena, he worked for a Kern construction, maybe Kern & Tabery, Inc.?? they gave me a hat but 40 yrs ago

[@houselightkell]

Sounds like an absolute legend

[@lassikinnunen]

Its not a new idea as such, but you can patent some new aspects about for how to do it, the idea itself is as old as air compressors and generators are.

[@helixhippie]

Years ago I met a couple guys from MIT who had designed, maybe patented, wind turbines that had compressors instead of generators. Utilizing subterranean storage in Texas. Although it will never happen, they wanted to take advantage of hundreds of thousands of miles of old oil field pipeline. They had quite a list of operations that could use stored air, far beyond electrical generation.

[@dfgaJK]

3:36 perfect opportunity to use a thermal camera to demonstrate the can cooling down.

[@LarsKuhlmannCourtwright]

If he'd let it go for a bit longer the ambient water would start to condense and freeze on the sides. It's a pretty clear visual indication.

[@uboat4]

Just saying but that's not can air... but a refrigerant in a can.

[@dfgaJK]

@@uboat4 indeed, "compressed gas" would be better

[@frederickbernet6689]

"have their compressed air and heat it too".... That one made me smile.

[@rickrack78]

I consulted for a compressed air storage startup called LightSail Energy. They tried to cool the compressed air by introducing a water mist to suck the heat out, store the heated water then reintroduce the heat as the pressurized air was released. I believe the company went belly up. (Most likely in my opinion from mismanagement of funds)

[@Hamletbls]

It is hard for me to imagine this succeeding. Why would you assume it is mismanagement and not just market failure?

[@rickrack78]

@@Hamletbls, I am only talking about the particular company. They were based on Oakland Ca and did a lot of (imo) extravagant spending. And very heavy PHD and high profile names employees. That face looked good to investors but cost the company a lot of money and diva kind of problems. There are many ways of storing energy and a lot of them require geological features to make them attractive.

[@williamhicks558]

I like the idea of using water mist, but I think doing it indirectly would be better to avoid the extra moisture in the compressed air.

[@AG-ig8uf]

@@rickrack78 Because that is the whole point of such companies. So it wasn't mismanagement, it was successful example of using scientism and fake techno-optimism for personal gains. Just like this channel and almost everything it comes up with. Baffles me that after so many years and countless busts people still buy into this snakeoil.

[@RP-hn1qc]

​@@rickrack78What do you think of energy dome and their supercritical CO2 66KWh per cubic meter battery? Do you still dable in consulting?

[@MrLargonaut]

The number of air puns in this video was absolutely deflating XD

[@sigataros]

i was winded by the end of the video

[@paulronge]

He couldn’t have compressed this video any more.

[@priestesslucy]

Matt's humor blows

[@marvelaturraz5405]

Clearly, I am breezing in a bit late to this, but I swear I'm not here to puff up my ego with a quick quip of some sort (lest I come across an airhead) nor to be a blowhard and push some expansive pontification about "the winds of change" which this process has the potential to... Wait. What am I doing here?

[@MrLargonaut]

@@marvelaturraz5405 Sucked all the air out of the replies. XD

[@jaymacpherson8167]

Also, the potential to use barometric pressure changes to store/release energy. This content reminded me of an experience doing field testing for design of a fuel spill cleanup. The location was a very large truck stop in Albuquerque NM, with asphalt or concrete covering the site and beyond. Wells had previously been installed for ground water and soil gas monitoring and extraction/injection. While placing magnehelic gauges at wellheads to monitor pressure drop when vacuum was applied at specific extraction wells, I started to pull off a well cap which popped off on its own and was followed with a strong and continuous flow of hydrocarbon-laden soil gas (of which I initially received a face full). I wondered why the previous caps hadn’t popped off with commensurate outpouring of soil gas. I took a moment to cogitate this change, seeing a flash of light, I looked up at the horizon to see a thunderstorm rushing toward us about 3 km away. We had to wait for the storm to pass as the pressure effect reverse-pegged our gauges.

[@tommussington8330]

The company I worked for back in 1986 had property along side Bethlehem Steel's old iron mine. There was a company looking at using the old mines for CAS it didn't pan out, but they put a lot of time and money in to looking at the mines to see if the volume was large enough. they were large enough but as you said it wasn't ready for prime time because of the heat issues and the moisture in the mines.

[@bibihunden]

In Denmark, we had an inventor named Jacob Ellehammer, who was among the first to fly in 1906. He was very interested in precisely compressed air, and built several boats with compressed air, among the famous "tivoli boats" in our well-known Tivoli Gardens in Copenhagen, which was later electrified only 20 years ago. He also invented the ejection pump, which is used on ships all over the world. The whole world is full of compressed air tools, so it's probably high time we looked at it again. Although a pressure tank can explode, it is not dynamite or lithium batteries.😜

[@jeschinstad]

When I built my home co2 system, I didn't exactly understand how everything worked and I tried to unscrew the bottle from the regulator without turning down the regulator first. It was hard as hell, so I thought I had done something wrong, but I used all the power I had and was able to unscrew it. The co2-bottle flew into the wall, bounced into the seiling and continued to trash most of my kitchen. Ever since then, I've had a rather healthy respect for compressed air. I'm lucky it didn't kill me.

[@mrkeopele]

OR GASOLINE!!

[@glenlongstreet7]

Many years ago, I read about a man in Pennsylvania (maybe) who bought an oil car from a railroad company. He buried it and used a wind turbine to compress the air in it. He then had a huge amount of stored potential energy. He used it to drive pneumatic motors to produce electricity for his home and workshop. I never saw any other information.

[@absaly]

compressed -air tech is being held back !

[@user-dr2pg8fk2i]

HEY! Thanks for advertising Factor. I love eating cafeteria grade food at a premium price while creating non-recyclable waste. Best done when watching videos about energy and the environment. Really lets me feel good about making the world a worse place.

[@Big_Un]

2:04 Punny guy, but you might have missed one there? "expand later", "compress the idea", Here's the main JEST! (I crack myself up!) Although, it's also possible that you have more refinement and judicious prudence than I do! LOL In all honesty, thank you for explaining what otherwise might be a dry subject in an entertaining way.

[@specialagentdustyponcho1065]

Why not use these caverns as a reservoir for cryogenic air storage? Rock and earth is fairly insulating, and if necessary you could spray foam the walls of a cavern for extra insulation.

[@jlindcary]

Yes, this has been discussed for decades. It remains, like most energy storage systems, material intensive, complicated (so a maintenance headache) and expensive for the energy stored. Can it do better than 70% round trip efficiency? Maybe 80% but that is still less than batteries which themselves aren't cost effective. I think it will be talked about for more decades and nothing much will happen.

[@Dang_Near_Fed_Up]

I agree, this is a boondoggle to sink tax money into in order to fleece the taxpayers again.

[@Jokerkles]

I remember reading a few years ago about the City of Toronto (in conjunction with numerous partners whose names I currently can't remember, other than Ontario Hydro) using compressed air as an energy storage medium. Their difference was that instead of drilling deep underground, they installed the flexible air bags they used on the floor of Lake Ontario to help provide pressure. They also used bi-directional motors on the pumps so that they could be used as drive motors during the night to pump air into the bags (when general usage was down), and then as generators during the day when demand outstripped supply. Due to governmental stupidity surrounding social media in the last couple years (combined with personal and relative health issues), I haven't been able to keep abreast of new developments with the project since about 2021. I would be highly interested to know how the project fared during a cold Canadian winter and in some of the recent heat waves, just to see if the plan was viable on a larger scale. Might be something to look into as a follow-up piece.

[@adamlytle2615]

That was actually also Hydrostor. But yeah there's no info anywhere about whatever happened with that, at least that I can find.... so I assume the test didn't live up the their hopes? I dunno maybe not

[@darekmistrz4364]

But that is what is mentioned in the material: We are trying to invent a solution where there are no predispositions for big water tanks (like a lake)

[@atrumluminarium]

There is another Maltese startup called FLASC working on offshore compressed air platforms for energy storage too. Their test platform has been used to store energy in the Grand Harbour for the last 5 years and now they're planning on deploying platforms around the Greek islands. The platforms being offshore can use the sea itself as a heat source/sink to get adiabatic compression.

[@Dang_Near_Fed_Up]

And as soon as it goes online the ecowarriors will go off the deep end, claiming it raises / lowers water temperatures enough to affect the ecosystem of the sea. So expect it to be shut down for ecological studies for decades (at tax payers' expense).

[@atrumluminarium]

@Dang_Near_Fed_Up it has been quite well received so far here and the compression rate is slow enough to be almost isothermal.

[@Dang_Near_Fed_Up]

@@atrumluminarium Local acceptance is not the reason ECO warriors will come out of the wood work to protest it. They are the unsuspecting pawns of rich people who would see the world starve to death in order to feed their pocketbooks via the existing infrastructure fuels, like oil. Some fat cat will instigate a protest, with provocateurs, if the process starts to impact their profit margins.

[@JonS]

The Kraftwerk facility is located next to the Autobahn and is used to power Neon Lights and the Trans Europe Express. All systems are controlled by The Robots using a Home Computer and Pocket Calculator. However, locals complain about the Boing Boom Tschak noises produced by the rubbing of Metal on Metal. [These are all songs by the pioneering German electronic music band, Kraftwerk for those of you thinking I am mad]

[@mattsheard2708]

@@JonS Wir fahr'n, fahr'n, fahr'n auf der Autobahn!

[@HammerOn-bu7gx]

Unless one reheats the air, most of the energy is going to be lost when the compressed air cools. Unless the cavity is so vast, the majority of the air doesn't have time to loose it's heat to the outside environment. This is why blow-down wind tunnel storage tanks are full of empty beer cans, or similar thin walled material. The cans absorb the inbound heat from the compressed air. When the air is released, the cans transfer that heat back to the outbound air. Granted, this is a short term, a half hour or so, ability before the cans start loosing heat through the tank wall.

[@Streethagore]

I was wondering about that but if when the temperature, hence the pressure, get down after some time, you can still input more air to reach your maximum pressure no ?

[@francisboyle1739]

This is just doing the same thing as your beer cans but storing the heat in tanks or other heat storage mechanisms, so instead of a half hour you get many hours or even days.

[@totally_not_ace6032]

@@HammerOn-bu7gx Mechanically compressing air is also extremely inefficient, I can't even imagine the energy loss a grid sized compressed air energy storage system would have

[@DanielJohnson-ps4xv]

You definitely will lose some pressure due to the air cooling it it will still remain pressurized.

[@darekmistrz4364]

@@totally_not_ace6032 Thats true, but also we have abundance of power in Solar and Wind turbines where energy loss isn't that big of a deal where comparable energy loss is 100% when we are not storing surplus of energy from Wind and Solar.

[@77gravity]

Along with flywheel storage, I think compressed air is probably the best solution for energy storage. Cheap, reliable, scalable, recyclable, uses basic materials and processes.

[@absaly]

oil cartels will be very angry at you now

[@jj5jj5]

4:04 “… enables their systems to have their compressed air and heat it too” One of the many fine, understated word plays (“have their cake and eat it too”) in this video. Well done, sir. 🎩👌

[@robroysyd]

The critical parameter for energy storage is kilowatt hours or KWH. Watt s is a measure of power, You need both values to evaluate a system

[@johngalt97]

This distinction is a constant thorn with electric vehicle characterizations.

[@geirmyrvagnes8718]

If we are going to be pedantic, kWh. But yes. Lost the thread when he started mixing those up.

[@beyondfossil]

I've encountered this problem before for official documentation on grid-scale battery storage. A lot of grid-scale battery farm official documentation from California PG&E is like this and I was struggling to dig deeper into the specs. I think one source for this problem comes from old fossil fuel power plant terminology standards where they have a given peak power rating (Watts) and then is just expected to provide that power for a set time duration like, say, 8hrs overnight. Also, to be pedantic, the actual unit is watt-hour (Wh) and the kilo- prefix for kWh is just unit scaling -- it could very well be mega- and giga- unit scaling for instance.

[@b43xoit]

For conversion to SI, note that h=3600s.

[@robroysyd]

@@b43xoit Indeed if you want Joules. The IEA gives figures in BTU and my father who was an electrical engineer had the initials ERG

[@punditgi]

You have compressed a lot of good information into a short video. Well done! 🎉😊

[@johncampbell9216]

I've been saying for years that the way we use wind turbines is all wrong! We need to stop generating the electricity at the turbine and instead use the turbine as a hydraulic pump! Pipe the hydraulic fluid from the turbine field to a generator building where the generators are driven by hydraulic motors. Between the turbines and the generator building, bury a dozen giant hydro-pneumatic accumulators... effectively giant pressure storage vessels! When turbine delivery is high, the vessels store the energy as pneumatic pressure. Flow control valves then deliver the (regulated) pressure to the motors at a steady pace, maintaining frequency modulation and using/preserving the energy in a controlled way.

[@Sharukurusu]

Agreed, this also reduces the amount of copper and rare earth metals needed for individual generators and transmission lines. Intermittency means when a turbine isn't turning all the resources tied up in the generator are idle, if they were feeding an accumulator you'd have less downtime on the most resource critical piece of the infrastructure.

[@foldionepapyrus3441]

I suspect the flow resistance in the pipes would completely destroy that as a functional system, let alone an efficient one. Its an interesting concept but I'd be very surprised if you can actually get the turbines to rotate at all in most wind conditions with a hydraulic drive system.

[@lewisreford8552]

Perhaps you are an un-recognized Einstein, but I'll bet 100,000 fully-employed renewable energy engineers, economists and researchers can provide you a few good reasons why wind turbines aren't connected to hydraulic pumps instead of generators . . . just sayin'

[@foldionepapyrus3441]

@@lewisreford8552 If there is one thing economist and engineers rarely do its think of outlandish and novel methods - both professions tend to put a great deal of emphasis on using the 'proven' stuff, and while researchers might by their nature come up with weird ideas they would like to try they actually have to get funding to study them... I don't think this concept would actually work well at any scale, but as I've only got gut feeling having not even tried to do the fluidic calculations... It might actually work very nicely at least at some scales, but I do doubt it as fluid resistance along those long pipes described would seem like it should make it very ineffective if it works at all.

[@papaix4387]

@@johncampbell9216 it’s the efficiency. Generators are ~96.5% efficient and the line losses are low. Hydros are 85? % efficient each direction or round trip 70+%. That’s from memory.

[@houssemmasri9861]

Wow, this is such a cool idea! Imagine if every house had a DIY compressed air system using big tanks like the ones we use for water storage. You could store excess energy from your solar panels by compressing air, and then use that stored energy when you need it. Plus, the heat produced when compressing the air can be used to heat your home, and the cooling effect when the air expands can help cool it down. It's a clever way to make the most of renewable energy, using materials and skills that are already available in the community. This could really help villages become more energy independent and sustainable!

[@AhTechus]

Not what I expected, but I learned a lot. Thanks for sharing

[@jimcabezola3051]

This reminds of that wonderfully inventive French firm that produced small cars/delivery vehicles that ran on compressed air. I like THIS idea, too. With all the hot air produced by Congress and the mainstream media, we could use this technology to tackle global warming and all our energy needs.

[@thewordofgog]

Was that Ligier? I seem to remember seeing/hearing them a few times whilst I was working over there

[@ralpharmsby8040]

Apparently there are plans for a compressed air storage system near Manchester in the UK. Not sure how these are going but I'll be interested to see how it goes.

[@jimcabezola3051]

@@thewordofgog I believe you're correct. I had to look it up. Ligier is still around creating racing cars, but I also believe they helped developed this technology, too. A company I found was called MDI, and a number of KZbin videos featuring this brand of compressed air vehicle are featured. Thanks for the nostalgic look back; I haven't thought about these cars for ages. These seemed very promising.

[@Transit_Biker]

A few years ago I saw a video demonstrating compressed air with power negative (it uses less power than it consumes) thermal management system. Been looking for this video/program ever since to share. It worked & they were looking to scale up.

[@anthonyperks2201]

Just a quick comment to note that max energy use doesn't peak after sundown, consumer draw does. Peak energy draw is usually in the middle of the day when industry and business air con is operating. The hotter the environment the more likely it is to be true, which aligns with solar usage.

[@aarons7975]

OR in the middle of the night, when it's cold as hell and everyone's heat strips kick in. Or in the morning when they wake up, take their showers, all the water heaters kick on, and all the griddles turn on to make breakfast.

[@GBOAC]

@@aarons7975show me one 24h graph what shows the peak at night

[@poochyenarulez]

@@aarons7975 most heating is still from gas, so electric demand peak will be during the day.

[@boredphysicist]

@@anthonyperks2201Wrong www.eia.gov/todayinenergy/detail.php?id=42915#:~:text=Electricity%20consumption%20in%20the%20summer,load%20peaks%20during%20the%20summer.

[@jb5music]

Because industry and business are not... "consumers"

[@jameseddy6835]

Ha Matt I really enjoy your programs. They are perhaps the best I have seen on any topic. I know that these programs must occupy a great deal of your time. But they are worth more than you can imagine to me. Many thanks.

[@tomdenny8507]

I truly believe that CAES could be the worlds answer to energy storage. I have been a fan of this method since I first heard of it probably 40 years ago. I don't know why it is taking so long for this technology to mature.

[@DavidKnowles0]

The world hasn't needed it. The grid could easily 10% or 20% or even more of electricity produce by renewables. It only when you get into 60s and 70s that large scale energy storage become essential.

[@AuxiliaryPanther]

See all the comments referring to efficiency issues as to why it hasn't panned out. If something doesn't save money, it doesn't get implemented. The only reason so many green energy options are implemented in the U.S. is because of government subsidies.

[@Dang_Near_Fed_Up]

@@AuxiliaryPanther Exactly so. In many cases the government is funding boondoggles they know will never work, simply to hide payoffs to their campaign contributors and to themselves via family members. Case in point: Have you heard about the shrimp on a treadmill experiment? It gets millions annually to see how cold water affects shrimp. Global warming don't you know.

[@zen1647]

3:36 Don't waste all that compressed air! You monster!

[@aisac21]

That pun game is top notch😅

[@surters]

"Or will it just cave under all that pressure"!!!

[@glenw3814]

😓

[@jasonallison8946]

Is this a new record for him?

[@michaelblacktree]

Yeah I think he cranked it up to 11 on this one. 😎

[@michaelwallace9291]

@@aisac21 lies

[@mayflowerlash11]

Also re heat storage. I have seen sand stored in an insulated container used as a heat store. The sand gets as hot as required by the compressor waste and stays hot for days. At any time expanding air generating electricity can be flowed through the hot sand, reheating the expanding air.

[@junkerzn7312]

I like the compressed air concept but you have to be careful costing-out battery storage because one of the biggest advantages of battery storage is that it can help with transmission line corridor congestion. A lot. As in removes the need to add more or larger transmission lines in many situations. That alone is worth billions. Compressed air is more like flow battery technology... the cost effectiveness is in scaling the storage component without scaling the power component. So just as with flow batteries, compressed air is not as useful for dealing with peak (4-5 hour) windows. Thus these aren't apples-to-apples comparisons. They are targeting different needs. -Matt

[@fujinshu]

That’s a great way to think about the relevance of different kinds of battery storage. Ultimately, we are going to need to diversify our methods of electricity generation and storage rather than sticking to one or two main methods, since they all have different uses and have different benefits and drawbacks that suit certain environments better than others.

[@GeraldMMonroe]

@junkernz7312 I am wondering if $57 a kWh LFP or nominally $20 a kWh sodium batteries will be strictly dominant.

[@junkerzn7312]

@@GeraldMMonroe Sodium isn't $20/kWh yet (that I know of). The LFP number looks right. But both are moving targets and there is a ton of momentum behind LFP. Sometimes the theoretically cheapest technology doesn't win when its competition has orders of magnitude more R&D and production. I suspect LFP will win out in this case. Sodium has quite a few drawbacks including an extremely wide voltage range. -Matt

[@GeraldMMonroe]

@@junkerzn7312 right but LFP hits a floor governed by the price of lithium, sodium can go below that. In the loooooong term sodium should win.

[@junkerzn7312]

@@GeraldMMonroe Not necessarily, the price of lithium has cratered due to over-production of lithium, and there is a lot more that goes into making a battery than just the lithium. Lithium-v-Sodium alone is not going to cut the cost of a battery in half or anything like that. The greatest cost savings is almost always in production scale, and I think it is safe to say that LFP battery technologies have gobs more scale than sodium. Whether that will remain the case we'll have to see. -Matt

[@marvelaturraz5405]

Hey Matt, I was hoping you'd have touched on the fundamentals of the compressor and air motor types because I'm probably not the only one who is curious as to how they can work so efficiently? And also, the air powered cars which they were developing fairly recently (I think it was in Europe somewhere). Those things actually had a pretty remarkable range, as I recall. It'd be interesting to bring up the specific tech they use compared/contrasted with industrial scale facilities. And lastly, it seems to me that phase change materials could be incorporated into the design plan of these systems in a more elegant way than even water (thermal) storage.

[@BradleyFordAus]

I assume you know of the huge chilled water "battery" in the Houston medical precinct. Essentially it is a huge storage of chilled water, in which it is released slowly throughout the day, and then charged overnight in off-peak hours. My company actually wrote the algorithm on when to "charge"/“fill" based on expected demand, weather, costs, etc

[@janami-dharmam]

these are innovative solutions if applied judiciously; for example chilled water systems can have high efficiency if used for local air conditioning (say a large building). Same ideas can be used for hot water (waste heat) used for heating buildings in winter.

[@jeffjwatts]

Chilled water batteries are used in industry that need a lot of peak cooling. Think dairy processing and that kind of thing. Usually they'll use a glycol ice slurry mix and it will supplement the Air Handling Units during the peak hot periods. This not only saves some electricity costs, it also saves the cost of buying additional AHUs that only run for 100 hours a year.

[@htwt]

3:28 There's no air in the can. A phase change is a bit different than simple adiabatic expansion.

[@marshallb5210]

6:05 so it's all hot air

[@Optimiser113]

Spot on!

[@nbrown5907]

Hey this is like Popular Science, neat stuff that mostly does not make it to commercial use. Cool to take a look at what MIGHT become popular.

[@akarna69]

Stop making korney jokes. 😄

[@stephanwaldchen]

He's talking about lithium ion

[@nachopascual96]

I'm surprised no one is looking into capturing the "cold" generated during the decompression stage. Considering cooling represents a substantial amount of our energy mix, the "cold" could be used to supply local communities' cooling needs

[@oggyreidmore]

I once read a proposal where we would repurpose the current national grid of compressed natural gas pipelines as a way to store compressed air that is powered by tidal compressors. It could bring tidal power all the way into the center of the country, and if there was ever a leak it would just be air instead of explosive and poisonous fossil fuels.

[@90xxxxkat]

@oggyreidmore a compressed air leak can be very dangerous but admittedly not as dangerous as a gas leak

[@richdobbs6595]

Yeah, combine a really diffuse, uneconomic power source with an inefficient means to store and transport energy! Winning!

[@oggyreidmore]

@@richdobbs6595 Good point. We should use coal power plants that are 35% efficient plus another 15% loss from transmission lines + kill the planet over time. Winning!

[@Dang_Near_Fed_Up]

While natural gas is compressed, it is at low pressure compared to that a compressed air system would need. Most homes supplied by individual natural gas lines is at about 1/4 psi. Compressed air lines are usually 80 to 120 psi. The existing lines simply can not handle the pressure load. I am speaking about distribution lines, like those in your neighborhood, not transmission lines like those feeding inside a distribution center.

[@oggyreidmore]

@@Dang_Near_Fed_Up That's the bottom of the range. They range from 1/4 psi to 200 psi. They can easily handle 120 psi.

[@northernmetalworker]

The amish use compressed air technology as well. I can't recall the video, but i saw a video of an amish store that had a cieping fan that ran on air, and even a washing machine!

[@RyanMercer]

"you can plan a pretty picnic but you can't predict the weatherrrrr"

[@mikecschmitt89]

@@RyanMercer forgot this reference until I heard this song, by chance, earlier today

[@RyanMercer]

@@mikecschmitt89 😂

[@komokaziboschetti]

I'm sorry Ms. Jackson

[@RyanMercer]

@@komokaziboschetti I am forrreeeeallll

[@mnhtnman]

Thank you and good morning!

[@Green_Tea_Coffee]

"Companies throw around superlatives like 'world's largest' and 'first' about as fast and loose as your typical KZbin comments section." Well done, @UndecidedMF, for sneaking a really solid joke in there.

[@Bergus6530]

Hello Matt. Using pumped water to compress air then release the water back to drive a generator seems to get around the heating the air issue. Thanks for all of your info on tech.

[@A.Lifecraft]

Honestly I don't get why we don't just use open-cycle heatpumps. Just compress air to release heat. Compressing air for any industrial usecase has a terrible efficiency because of the heat being lost at compressor-radiators. Also releasing compressed air into houses would cool these down without all the complexity of air conditioning, circumventing that relevant portion of electric grid capacity used on AC. Imagine your local community using surplus solar to heat a large volume of water during the day. Meanwhile, compressed air is stored. During nighttime, that compressed air gets delivered to your home. Absorbing heat and cooling your house, that air now expands to get a tiny turbine in your basement running, providing electricity. It would simultaneosly provide a 12 hour shift on solarpower and distribute that energy to housholds.

[@RayTheMickey]

Your house would be very humid unless the air was kept very dry.

[@darekmistrz4364]

@@RayTheMickey When the air is compressed, and later heat extracted by "heating the water", it should lower the air temperature down and should allow for condenstation to be collected and removed from the air storage

[@Dang_Near_Fed_Up]

I think you are underestimating the complexity of a system like this. As a single home option it may work, but as it scales up to make it work for more homes it becomes astronomically more expensive and complex. The best example I can think of to use to make my point is a rubber band airplane, it works fine on a small toy, but it could never get a Cessna to fly beyond a few miles, much less a commercial airliner to travel between continents. Look at the cost to pipe in natural gas to a neighborhood, that is about comparable to doing just an air line for your proposed system. Now think how many issues like leaks those gas lines have. And an air line will be required to hold far higher pressure.

[@A.Lifecraft]

@@Dang_Near_Fed_Up You do not need to explain complexity of systems to me. Also the rubberband-aircraft is a bad example (because energy storage in rubber is lower and does not scale linearly with mass like it does in carbohydrate-propellants). Nitrogen liqifies at 34 atmospheres at room temperature, these are not dangerously high or hard to manage pressures. You can almost go by standard hardwarestore piping. Also if it leaks, this is not toxic, flammable or explosive, so not that big of a deal. Where I live, distribution of natural gas is as normal a thing as distribution of 3-phase 400V electricity and distribution of drinkable freshwater to each and every home. Lets say one would go by 50 atmospheres insulated liquid nitrogen pipes, it might be more practical to build local coldgas-turbine-generator-facilities for clusters of 10-20 homes or one per neighborhood, but still totally manageable. Heatpump-based air conditioning in every home also needs a lot of infrastructure, so build that 40k dollar heatpump in every yard or pipe into that lokal heat-cold-and-electric hub in the neighborhood, it does not sound that expensive from that point of view...

[@RayTheMickey]

@@darekmistrz4364 If the air is wet going in it is wet coming out. Ask the Thresher. As the air decompresses the ice formed can actually block the lines.

[@russellsmith3825]

I have been pitching the idea of placing wind driven compressors at old oil well locations and reusing the pipelines to gather and store the compressed air, to be used later for generation.

[@adam-g7crq]

I think liquid air storage ( liquid air batteries ) is a better option than compressed air, you have more options to where you can site these facilities say at switching stations, I suppose both options would probably be backed up with lithium iron or sodium iron batteries to allow them to spin up and connect to the grid.

[@markumbers5362]

Highview, after 17 years of development, recently secured 300 million quid to build 4 liquid air storage facilities in the UK and they are close to closing a big deal in Australia. Liquid air always looked the answer to me. Like hydro that requires no new tech, easily decommissioned and recycled and can be built out on dead flat desert next to a massive solar farm and is safe enough to operate in the middle of densely populated cities.

[@adam-g7crq]

@@markumbers5362 I find it the most promising grid storage solution so far, and it's exhaust is just fresh air.

[@dianapennepacker6854]

Really? I gotta look more into those batteries again, then. I have seen one video on it a year ago or so, and it sounded expensive. Maybe I should check out other designs. There were some redox batteries that also looked promising with their specs, and future chemistries. I thought a bunch were starting this year, but I haven't heard much after that. Battery storage tech is moving so fast. The demand for it too.

[@adam-g7crq]

@@dianapennepacker6854 liquid air batteries use off the shelf components that have been used in a myriad of different industries so there very available and tried and tested there's a lot engineers available to install this equipment.

[@V3RTIGO222]

Cryogenic Air Storage, I had to look it up because air can technically be compressed until it is liquid state, but the CAS system uses a cryogenic refrigerator to store the liquid. The problems is requires constant power to sustain the cryogenic state, while CAES can be stored near indefinitely without any power use.

[@warrenarmstrong9885]

Perhaps someone has already commented on this, but do we need to consider pollutants the air might pick up in the cavity? Salt mines seem safe but unused coal mines, gas or oil wells might be a concern. Matt, thanks for this and all your other videos, they are great!

[@hermaeusmora2945]

Do a video on biogas, please. We've got like 8 billion people on this rock, each of whom take a poo at least once a day. We've got tens of millions of livestock animals and millions of pets...both of whom produce a lot of poo. With all that poo we could be produce a lot of power by burning the methane.

[@patrickcrist4632]

Passing the biogas through a fuel cell would produce power without the combustion products.

[@portalkeeper978]

The poo replenishes the soil, and we need the soil for food.

[@commonsense.1014]

He made one. It's called poo power.😂

[@hermaeusmora2945]

@@commonsense.1014 Thanks homie!

[@12pentaborane]

​@@patrickcrist4632 Might not get combustion products but it still generates CO2.

[@gordonlawrence1448]

There are multiple ways of reducing the need for grid scale storage. Once sodium cells become more freely available and the price starts to fall, 30kWh of domestic storage is within reach for about half the population, at about $10,000USD add in a PV roof and the most efficient homes should not be drawing any power from the grid. I am in the UK and have got my total energy usage down to £1100 per year. I'm working on radically reducing that.

[@michaelclement1337]

Sounds like it won't be long before batteries become cheaper than compressed air

[@Bzhydack]

Still remains problem of longevity. And very eco- unfriendly elements.

[@Music_For_Life_YT]

Good to know ! CAES using salt caves, former mining sites, and depleted gas wells presents significant potential, further research and development are necessary to optimize its performance and address potential challenges. By leveraging these existing underground spaces, CAES can play a crucial role in integrating renewable energy into the grid and reducing greenhouse gas emissions.

[@deizel295]

Matt, take a look at the back of that can of compressed air, it's not compressed air. It's R134a refrigerant. Read the chemical name and Google it. NOT compressed air.

[@StephenSarmiento-g1e]

@@deizel295 *compressed gas

[@CausticTitan]

It being a refrigerant is not what makes it cold. It's a refrigerant because it is a gas which can phase to liquid without immense pressure. What he said about gasses cooling down as they expand is true regardless of which gas he is talking about. It's described by the ideal gas law, where (P1 x V1) / T1 = (P2 x V2) / T2

[@Memevze]

@deizel295 too late I already stocked my sub full

[@jasonschultz9570]

@undecided with Matt Ferrell. I have this idea, not sure if it's ever been attempted, but you'd probably know. What if you drill into the ground like a well, and hang a weight from it that uses gravity to spool a generator as it decends. Solar could pull the weight up during production, and gravity would produce at night. A gravity battery. Making the weight a container that's filled with water, and the addition of a water pump or two could potentially boost the effeciency. On a small scale used at people's homes, like a battery bank, I feel like it could totally work. Not enough energy storage? Add another well. There are loads of benefits. Very little mining of materials, and low to no chemicals that can leach into the ground. No battery degradation. Very few moving parts.Cheap and known technologies With very little maintainace they could last ages.

[@frederickheard2022]

It’s been thought of and covered in previous videos on this channel

[@Group_IV_Solar]

@@jasonschultz9570 Look at Energy Vault and Gravitricity. Lots of disused mines out there, seems like a no brainer…until you look at the “energy density” of gravity. You need HUGE masses to get any meaningful energy. Energy Vault started by using fresh concrete blocks. Seems much more resource intensive than the off the shelf equipment for compressed air. I think they are using repurposed construction waste now.

[@wolphin732]

3:48 that can of "Air" is not actually air but a refrigerant, as they would not be able to store enough air in it.

[@axelBr1]

Exactly, because if it was compressed air in such a flimsy can, you would only get a sort puff of air out of it. Which goes to make the point that most of this research is just wasted money, these sites are never going to store significant amounts of energy. The quoted examples are of plants producing 200 to 300MW, no duration given, whereas a typical generator at a UK coal fired power station was 660MW, and most power stations had multiple units.

[@axelBr1]

@@Gecko88 That might be the point he’s making, but the point being missed is that you can’t store much energy in a compressed gas. And secondly, all expansion engines expand gases that are around 1000°C, gas turbines and internal combustion engines, and about 500°C for steam turbines. In industrial compressors the gas is compressed in stages to keep the compressors cool for mechanical structural reasons, so you’re generating vast quantities of low grade heat; no where near the temperatures required to get a large amount of energy out of the turbine

[@tom4ivo]

I've always wondered why not just insulate the tanks that store the compressed air? If the air doesn't cool down after being compressed, it doesn't lose energy. Releasing the air will cool the tanks back down, but it will simply cool itself down to what it was before the compressed air was pumped in. I can see there being a problem if the air gets too hot for the materials, but I'm sure we have the tech to deal with those temperatures already.

[@J.A.Smith2397]

The amount of word play on this is delightful lol

[@paperburn]

I did not like it, I found it PUNishing

[@wannabewallaby1592]

"closed loop water reservoir" (shows an open pool of eater 😂)

[@geraldalbrecht848]

Hallo Matt, this is Gerald from Germany. Since you are using this automatic translation in your videos, I don‘t watch them anymore so often. The german is terrible and very fast. as it starts always in German, I have to reset it to English. This is a bit of a hassle and keeps me away from watching your videos.

[@tibsyy895]

You are so comfy 😅

[@tibsyy895]

Don't you worry. He will be fine without you, I guess 🤷🏼🥴😅

[@policeman1104]

Bin auch aus Deutschland und hab das Problem nicht :)

[@geraldalbrecht848]

@@tibsyy895 no one ask for your opinion

[@tomcoryell]

The “handheld cans of ‘compressed air’ aren’t AIR at all. Come on Matt, please don’t perpetuate this ignorance. It’s usually hydrofluorocarbons or some such.

[@JonathanEmery-e9d]

I was curious about the temperature issue when I saw the thumbnail, my first thought was to slap a bunch of Stirling engines on the air input/output to gain more energy from the temperature difference.

[@CraigLandsberg-lk1ep]

The British have been using mains water supply pressure to create compressed air pressure batteries for over a hundred years, it got banned in the 1960's😢who knew

[@adblocker276]

Why banned?

[@theelectricmonk3909]

Have we? I'd love to read more about that, as it's not something I've heard of. There used to be a hydraulic power system available across London, which finally closed in 1977 (probably because electricity was ubiqutous by then). Liverpool had a hydraulic company too; it opened a little later than London's, and closed in 1971. I've heard of the London Pneumatic Railway, but nothing about compressed air batteries (or air as a power source) other than recent developments.

[@CraigLandsberg-lk1ep]

@@theelectricmonk3909 in Britain they had 'acymulators' tanks of water mounted as high as your roof or building, and was filled by 70psi mains pressure, and you could drive a water turbine electric generator every time you turned the tap on, or you could use the pressure and weight of the water to drive air tools or anything you could think of, it can still be done now! If you want to know more look up Murray Walker Smith from the UK, one of his sites is TnT, Thinking and Tinkering, and just put in water gravity batteries or whatever you are interested in, get back to me if you want to know more 😅 Craig our, from Australia 🌏

[@replikvltyoutube3727]

Didn't have loicense for them

[@davidrathbone5581]

​@@adblocker276 I think they wasted a lot of water.

[@isb170swap8]

Just a thought about the heat and cooling due to compressed air, it could be used as a dehumidifier and produce water for drinking?

[@williamjanak2013]

Never be a coward, always embrace the puns.

[@robertYTB78g]

When watching Matt I feel we can solve all manner of problems when we need to. When watching the news I feel some invested interests want to do all they can to stop that happening.

[@MartynDerg]

"canned air" is actually refrigerant, not air. but yes, decompression means lower temperature, so the principle is the same

[@GBOAC]

Why does it have to be a refrigerant? You also have those spray cans to blow away dust. Same way alcohol can mean a drink, sanitizer, fuel, all depending on context. No reason to play the *actually* card.

[@petewood2350]

I saw your video a couple of days ago, and was trying to remember a video I saw on another Chanel where they compressed air with flowing water, with a piece of equipment is called a Trompe, and I saw it on the Practical Engineering YT Channel, where the You Tuber made a model of a Trompe.

[@GarySBCA]

Too many mediocre puns. It was PUNishing.

[@hamaljay]

@@GarySBCA punny.

[@jirislavicek9954]

Similar technology is used for de-liquifying LNG (Liquified natural gas). It is good to have such a plant near a heat source or use the heat from the ocean for example

[@TeamCykelhold]

it's unrealistic to expect a private company to invest millions in using excess energy to store when there is no such guarentee for excess energy. And excess energy also is not free like some would like to think. It would have to be bought just like every other energy since when there is storago it would no longer be excess. That leaves only government as investors. It is very very very unlikely to happen on a large scale.

[@FalbertForester]

Utility companies have some incentives to build grid-scale storage to use to level their loads, and to time-shift production - when the wind is blowing to when it's not, or from when it's sunny to when it's not. There are good economic reasons to build storage.

[@BearBig70]

​@FalbertForester I usually just crank up rhe diesel-gen when I need excess energy. Mainly because liquid fuel IS stored energy😃

[@BearBig70]

I don't know why not, they could literally sell some energy twice. Besides, that's there excuse to charge so much money and make profit, because they "take risks" and we're "smart" to figure it all out.🙄

[@thematronsmilitia]

Almost like we need planned economies. Has anyone tried that before? 🇻🇳🇰🇵🇨🇳🇨🇺🇱🇦

[@burgels]

Writers need a bonus for this episode. Epic puns and word play throughout.

[@moletrap2640]

We are so kidding ourselves with intermittent renewables like wind and solar. Solar will require a few days of storage and wind will require up to weeks of storage (look up the wind doldrums in the North Sea/UK in 2021). Lithium ion is barely affordable for a few hours of storage, and is mostly suitable for grid frequency stabilization. And there is no viable technology for long-term storage - none. The longer we kid ourselves that wind and solar are the answer the worse our children's futures will be. The only viable renewable at scale is nuclear energy. In the 70s France went from 0 to 80% of all power being generated by nuclear less than a decade. In South Korea and China they can build a nuclear power plant for 1/3 of the cost of the US. If we were serious about defossilizing our grid, we could do the same. We are fiddling as Rome burns.

[@rtmaples]

Could you store the excess heat to sand batteries?

[@cortexcarvalho9423]

I saw a video showing a mountain in China with a large water reservoir on top of a mountain. And the narrator of the video wondered about the reason. Watching this video now, about energy using mountains and compressed air, it seems very similar.

[@FalbertForester]

Compressed air railway locomotives have been in use since about 1890 or so - they are used in industrial locations where steam or heated exhaust would be problematic, and often compressed air is readily available because of other industrial processes at the site.

[@coin777]

0:01 Russia Sochi olympics 2014 Would strongly disagree.

[@kashmiri4523]

@@coin777 so would the united arab emirates

[@heyjohnsmith]

0:01 Cloud seeding would strongly disagree

[@byronwatkins2565]

First, pumping the hottest gas into the heat storage's center and spiraling the gas outward through cooler and cooler storage media will minimize heat losses and better achieve adiabatic cooling of the compressed gas. Second, removing water vapor by condensation before compressing will also improve efficiency. Third, CO2 could be removed from the compressed gas (and the atmosphere) by chemically bonding it to a suitable substrate. Possibly, the product compound could have value for sale. High pressure and high temperature are typically ideal conditions to promote chemical reactions.

[@cleric7788]

This will cause the same problems as fracking.

[@Ryan-ff2db]

No it won't. You might want to look up fracking and how they do it. This is a totally different monster.

[@Warp9pnt9]

@@Ryan-ff2db Displacing aquifers with gas, patently bad idea. Squeezing old oil fields, natural gas pockets, and polluted sites with highly compressed air, to drive toxic materials potentially up into aquefers, not a great idea. Sites should be restricted to things like salt mines or man-made metro systems, until further independent scientific study answers the questions about safety.

[@guillaumevincent716]

i dont understand how you can compare that with fracking. if its leaks, its air that is coming out as opposed to oil. Can you explain your point please.

[@janami-dharmam]

Not correct; these are rather low pressure systems because high pressure systems are high cost.

[@cleric7788]

@@guillaumevincent716 My point is when you increase the pressure it will disturb the ground. Causing the mini earth quakes and release of gases in to the ground water. There is gas in a lot of areas its just not commercially recoverable. Would you want one of these high pressure storage areas built under your property?

[@jimsvideos7201]

It seems that compressed air storage has the advantage of being able to economically absorb pretty much any amount of electricity. Also, a brake car for trains going downhill could dump that energy into high pressure air rather than heat, then dump that air into a local storage facility.

[@spiritofvoljin8561]

"We can't control the weather, yet" To your knowledge we can't, but we're also not privy to secret tech undisclosed by our governments.

[@StapleCactus]

I switched from compressed air tools to battery because I learned the efficiency is something like 40%. I can't imagine making compressed air for electricity generation will be viable, even if they manage to break the 70% mark. I still think the rust battery is a great option.

[@samiktiri]

Whichever way you look at it, regarldess of how much you compress if air has even lower energy density than batteries, complete waste of breath, pun intended

[@spenceralridge4958]

While I agree that energy density is important, it is far less important for stationary power storage.

[@fangdenhahn]

There are other reasons as well. In a stationary use use case one deciding factor is the ratio of cost to capacity

[@bencarignan2711]

Energy density is of little concern for grid scale storage.

[@de0509]

These things would be in the "middle of nowhere" e.g. places that used to be mining towns. If the land area is so much cheaper then whats wrong? In this case what needs to be compared isnt energy density, but cost for the storage

[@dylanmiley5642]

The resources required as well as the lifetime are also crucial. We cannot ethically continue to rely on rare earth metal technology. And the degradation of batteries is a major concern. optimal battery usage requires that the batteries depth of discharge does not exceed 20%, meaning we have to oversized batteries by a factor of 5 to preserve the life. At the end of the day, batteries are not the way for grid storage unless some miracle material emerges.

[@AdvantestInc]

The potential for compressed air energy storage (CAES) to provide long-duration, cost-effective energy storage solutions is truly fascinating. It’s exciting to see how technologies like these can complement existing energy systems.

[@anguscampbell1533]

Maybe CAES systems should utilize and store the waste heat in daytime from PV farms to reheat the air before it passes through a turbine?

[@trepseb6798]

Great Video, but I tried to check twice and did not get for how long A-CAES can store power or how fast does the energy storage decay? I assume since heat is being stored this storage will get lost through time making it less efficient the longer it is stored. Are there numbers on how the decay looks like? And how long the storage can last?

[@pauldreze3414]

Grace à l’hydrure de bore on peut garder beaucoup d'hydrogène à l'état solide. Grace à l’ammoniaque on peut garder beaucoup d'hydrogène à l'état liquide. Grace à un béton carbone ciment on peut garder de l'énergie électrique comme un condensateur. etc

[@domenicobarillari2046]

Matt, I know you see your work as exposing the public to new ideas in regards to energy technologies and having initiating intelligent discussions about them, but as a physicist.engineer I often chuckle at the variety of ideas often devoted by inventors out there relying on heating or compressing a liquid (or even sand) in the drive to store precious electricity. Electricity is more or less "thermodynamicaly pure" energy in the sense that it takes little effort to convert 1 joule (watt-second) say into nearly exactly that amount of heat or work - these two being the be-all and end-all of energy uses when you think about it. No other energy conveyance is as direct and efficient for running a resistance heater or good quality electric motor, respectively, in these roles. That is why batteries are critical to a future all-electrical economy. No other type of device, as you point out, gives the return on energy that approaches 100%, either theoretically or in current practice. Anything that involves later running a turbine means inevitably large losses in the conversion of pressure-energy into a mechanical/electrical equivalent. The best turbine will only give a 60 to 70% yield on the energy stored in a gas - this is almost a thermodynamic restriction. On top of that, the apparatus is inevitably complicated and requires great attention for good performance. In the absence of profound new fluid mechanical principles, this always make fluid storage inefficient wrt to a well designed electrochemical storage cell. The public show always be told these things when alternative energy firms try to put the less ideal systems into the running. There may be other political, economic or technical design forces at play when selecting CAES for some particular, very large plant that may have other needs than electricity, but it is dis-ingenious to introduce these systems as serious contenders against battery farms otherwise.

[@paul1979uk2000]

I think we need every energy storage solution we can think of, even thought I think many of these will likely be short term niches until more localised better solution come along. Over the short term, a mix of on-site and big off-site renewable energy generating and storage is needed but long term, I'm hoping we'll find solutions to produce and store the energy at a more local level, and if we had an effective way of producing wind with solar in urban areas, that would go a long way in solving some of these problems being that solar and wind would complement each other really well and you usually get more wind when there's less sun, it would also go a long way in reducing how much energy storage you need if you can generate energy more consistently. So for now, I think we need every solution we can think off that works when it comes to energy generating and storage of that energy, but longer term, I think decentralising it and doing it more local will be best once the tech is advanced enough to do it as that would offer us far more control over the energy we produce and use and would reduce the price a lot by not needing a grid network which cost a fortune to maintain and reduces the benefits of lower bills to consumers, so off-grid is how I would prefer to see it as then you could more or less reduce your bills to almost zero, which will likely never happen with a grid style system with renewable energy because of corruption in the system and because of how costly it is to maintain the grid network.

[@chrisperrywv]

You know that clip of that short dude at a club or wedding reception that is going hard ok “turn down for what” but the DJ plays dancing queen at the drop? That’s how I feel when he says “I’m Matt Ferrel, and this is undecided” and he doesn’t play his old theme song! I feel so betrayed.

[@Friedbrain11]

I like the idea of using already played-out mines, as this means the CA can be set up and running quickly and more easily. I believe this type of nonfossil fuel storage and production is what will run the world in the end. Only thorium seems to offer more for less.

[@5pac3man]

Came for the wordplay. Was not disappointed. "The key a-word here isn't advanced, it's…". Thanks Matt for always being informative and entertaining.

[@miguelangelmungue]

Thank you for your video. Does somebody know what is the actual storage capacity of the plants mentioned in the video? Matt spoke about the power of them but not the energy they can actually store (the 1 MW plant is very different if it can deliver that MW for an hour or for half a day). Thank you in advance!

[@jellybean2032]

imo this is going to go boom, very boom!!!

[@stevesedio1656]

Stirling Engines use a regenerator (in the 1830's) to capture the heat before the gas moves to the cold side. That increases efficiency, but has it's limits.

[@mrpicky1868]

interesting cycle. specially with heat preservation upgrade. BUT makes me instantly think why not just capture energy as a heat . round trip would be even more efficient and you dont need to look for leaky cavity

[@mintakan003]

Just like there are different tiers of computer memory (e.g. RAM, SSD, tape, disk, ...), I suspect we'll have different tiers of storage. Each with their own performance characteristics and economics. The first tier, which is already existing technology, and deployed at large scales, is LFP. And if we struggle for lithium supplies, sodium is next on the line for stationary storage. This is good for frequency regulation and time shifting (4-6 hours), and grid stabilization services. (Also, integrating other sources of energy, now that one has a buffer.). After this, is generally called "long duration storage", usually defined as 10 hours or more. This area is still wide open. Just as a matter of basic physics, there are lots of different ways to do energy transitions, and storage (chemical, thermal, gravimetric, mechanical, ...). CAES probably fits in this category. Potentially, iron air batteries also. These are usually not as efficient (except for maybe hydro). But they allow for more mass, and longer duration. And the economics maybe better, for this purpose. And then there's seasonal storage (e.g., through the winter). Don't know what to do with this. But I suspect we'll need to think about whole integrated systems grids, with various resources, but coordinated, and would incorporate even fossil fuels (e.g., diesel gen sets, natural gas peakers, etc.). Capital costs for fossil fuel generator backups need to be lower. The intent is to use mostly renewables (with storage). When one doesn't have a choice, then use fossil fuels every once in awhile (e.g., a few weeks during the year). Still a net gain. Eventually phase out the fossil fuels for something like biogass, e-fuels such as methanol, ammonia, ... which still offers something like a dispatchable portion of one's portfolio.

[@vlaardingerrr]

How viable is CAES for season storage for your own house? If u store the air in industrial canister with 700 bar how much m3 compressed air will u need to have 1 mwh of electricity in the winter months?

[@MatsEngstrom]

Apparently only 15m3 (cubic meters) is required for 1MWh. But a tank pressurised to 700 bar is not something I'd like to have around me.....

[@罗建-g4h]

可存放 700bar的压力容器非常昂贵，最悲剧的是光容器成本就可能20年无法回本，还不用配置其他设备。政府对大型的I类压力容器会有严格监管，监测和维护对技术要求很高。压力容器成本完全可以压垮非盐穴case项目。

[@shawnr771]

Very cool. Thank you for the commentary.

[@070-pavani6]

How can we calculate amount of land required for compressed air energy storage for 8MWh capacity