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Goldman Sachs invests $250M in compressed air energy storage

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Re: Goldman Sachs invests $250M in compressed air energy storage

#81

Post by usrusr »

nemacol wrote: post #59

I would like more detail on the "Thermal management system" and how long it could store the heat it captures. One of the benefits they touting is "Long duration energy storage" I would think the limiting factor would be the ability of the thermal management system to retain the energy it captured to reheat the compressed air. Am I thinking about this correctly?

To the best of my knowledge that thinking is spot on.

A possible component that might be missing (in the thinking and/or in the proposed implementation): the stored heat could also be utilised separately if needed, so if you have an intermittent heat consumer and an intermittent electricity consumer you could consume the heat first, then leave the remaining compression energy (what you could recover without reheating) "forever". Bonus points if you also happen to have a coolant consumer to benefit from the temperature delta caused heat loss or premature heat consumption.

Re: Goldman Sachs invests $250M in compressed air energy storage

#82

Post by OneLeggedCat »

JohnL4 wrote: post #53
tikkabhuna wrote: post #22

Earlier quoted context omitted.

Totally out of my depth here, but does cooling the gas down have the added benefit that it'll be heated by the earth whilst stored?

I'm guessing not. Earth's heat is way lower down. Think of a cave: always cold. I think what's going on is they're taking the heat out and storing it more efficiently than just dumping it down the ground, where (1) it would leak away, representing energy loss, and (2) as it leaks away, the air would lose pressure. (It would leak away b/c it's harder to insulate an entire mine, basically.) So, they pull it out ahead o…

> Earth's heat is way lower down

Very incorrect.

Re: Goldman Sachs invests $250M in compressed air energy storage

#83

Post by emptysongglass »

Raidion wrote: post #62
JohnL4 wrote: post #53

Earlier quoted context omitted.

I'm guessing not. Earth's heat is way lower down. Think of a cave: always cold. I think what's going on is they're taking the heat out and storing it more efficiently than just dumping it down the ground, where (1) it would leak away, representing energy loss, and (2) as it leaks away, the air would lose pressure. (It would leak away b/c it's harder to insulate an entire mine, basically.) So, they pull it out ahead o…

This isn't correct. Deep mines are notoriously hot, because you're digging towards magma. Google says temps increase by 3° C for every 100m.

Naive question but couldn't our forerunners who otherwise succumbed to cold in harsher climates have exploited this fact to dig subterranean villages and towns?

What's the element I'm missing as to why they didn't?

Re: Goldman Sachs invests $250M in compressed air energy storage

#84

Post by hannob »

Murkin wrote: post #70

Can someone explain why this is better than just using pumps to pump water up from the reservoir and extract the energy with when the water returned back?

Pumped water only works if you have the right conditions. I.e. you need a certain altitude difference and enough space to have an upper and a lower water storage facility.

Pumped water storage is very efficient and an established technology, so when it's possible it's a good choice, but it's not possible everywhere.

Re: Goldman Sachs invests $250M in compressed air energy storage

#85

Post by WJW »

karmakaze wrote: post #51
slingnow wrote: post #41

Earlier quoted context omitted.

Can you name a method of large scale energy storage that isn't dangerous if done incorrectly?

I think the comment is more about being easy to do incorrectly/dangerously. Pumping water up into a reservoir seems easier/safer.

Lots of water in a reservoir is not particularly safe in itself. For example, in December 2000 at the Grande Dixence a high-pressure pipeline from the dam burst, causing a landslide that wiped out a small hamlet and killed three people. It's also not hard to find reports of massive amounts of casualties and/or property damage from dams that just outright fail.

Re: Goldman Sachs invests $250M in compressed air energy storage

#86

Post by nemacol »

themanmaran wrote: post #77
nemacol wrote: post #59

I would like more detail on the "Thermal management system" and how long it could store the heat it captures. One of the benefits they touting is "Long duration energy storage" I would think the limiting factor would be the ability of the thermal management system to retain the energy it captured to reheat the compressed air. Am I thinking about this correctly?

On that note do you have a good explanation for why the air needs to be reheated? I didn't quite understand that from the video.

Warm air takes up more space. If you cool it before pumping it into the ground you will not waste time/energy. If you pump warm air down it will lose heat into the ground and shrink and you would lose capacity - pumping that last x% the tanks will be fuller until they cool down.

You warm up the air on the way out to expand it and you get more air to spin the turbine. More bang for your buck.

I believe is the thinking.

Re: Goldman Sachs invests $250M in compressed air energy storage

#87

Post by buryat »

laputan_machine wrote: post #48
nkurz wrote: post #7

Interesting. There's a good video describing the operation here: https://www.youtube.com/watch?v=cOWjwwKSR78 After watching it, I now understand that they aren't flooding the entire borehole, but rather are building a smaller high-pressure chamber at the bottom. The chamber is connected to pipes to a surface reservoir. When air is pumped into the chamber, it displaces water up toward the surface. When generating, the…

The big question is how on earth are they digging out these caverns? That seems like a huge challenge, given that they're so far underground. Everything else seems relatively straightforward

lots of mining caverns already had pressurized gas that was extracted, so those caverns are pretty tight to pump back some air

Re: Goldman Sachs invests $250M in compressed air energy storage

#88

Post by ds »

fenixnuke wrote: post #69
ds wrote: post #38

Can someone explain their revenue to me? They claim 1m in revenue from their existing product which is: "1.75 megawatts (MW) of peak power output; a 2.2 MW charge rating; and 10+ megawatt-hours (MWh) of storage capacity" How does that equal 1m in revenue? You have to pay to charge your air-battery during low-cost hours and then discharge it during high cost hours to make the difference in revenue. The issue is, you c…

They are likely operating on the wholesale markets, which are market priced. For the western grid there is a significantly wider price range of prices. On peak days in the summer, prices can go up above $1,000/mwh in the late afternoon for several days. During the late fall/early spring, there are negative prices in the late morning (like $20-$50/mwh) due to extremely high solar production and low demand, so utilitie…

Im familiar with energy markets. Im also familiar with the fact that any serious seller or buyer of energy locks in yearly pricing contracts and is unaffected by these swings. Any serious datacenter or industrial buyer is not relying on spot pricing. These energy markets also dont exist in every state.

Re: Goldman Sachs invests $250M in compressed air energy storage

#89

Post by lbriner »

2OEH8eoCRo0 wrote: post #68

Has anybody considered building flywheels into each wind turbine?

I'm not sure how that would help? If you had a flywheel and you didn't need the energy, what do you do with it? At least without a flywheel, you can easily stop the turbine.

Also, any flywheel that would add significant difference would probably weigh hundreds of tonnes, which would make construction massively more expensive and difficult.

Re: Goldman Sachs invests $250M in compressed air energy storage

#90

Post by KennyBlanken »

epistasis wrote: post #67

Grid storage is going to be big business in the future, on the order of size of storage for electrical vehicles. (And these will certainly not be mutually exclusive markets! Vehicle to grid tech will become widespread, as is already seen in the new F150 Lightning truck). Lithium ion will dominate for the foreseeable future, as the industry has scaled to massive sizes and already, and has the advantage of being curren…

> one of the top contenders to watch is Form energy, which has a rust-based battery.

Form is still in the cell prototyping stage, as best I can tell - maybe not even that. There's zero information on their website about where they are in the development process or really anything substantial about their design.

ESS on the other hand has a design they've had out testing in the field for a couple years ( https://essinc.com/ess-inc-to-deliver-two-energy-warehouse-s... is one such location) and has been shipping actual product: https://www.businesswire.com/news/home/20211115006337/en/ESS... and they've been pretty open about their design, though some of their old whitepapers have been removed from the site.

Competition in the market is certainly a good thing, but Form needs to do more than just have a shiny website, a screengrab of a zoom employee meeting, and a blog with 'industry insight' posts (because they have nothing to show for tech/product.)

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