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CO2 batteries that store grid energy take off globally

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Re: CO2 batteries that store grid energy take off globally

#31

Post by lambdaone »

to11mtm wrote: post #30
lambdaone wrote: post #8

This seems almost too good to be true, and the equipment is so simple that it would seem that this is a panacea. Where are the gotchas with this technology? Clearly power capacity cost (scaling compressors/expanders and related kit) and energy storage cost (scaling gasbags and storage vessels) are decoupled from one another in this design; are there any numbers publicly available for either?

I don't know numbers but I at least remember my paintball physics; As far as the storage vessel, CO2 has much lower pressure demands than something like, say, hydrogen. On something like a paintball marker the burst disc (i.e. emergency blow off valve) for a CO2 tank is in the range of of 1500-1800PSI [0]. A compressed air tank that has a 62cubic inch, 3000PSI capacity, will have a circumference of 29cm and a length…

Fantastic detail, thank you.

Re: CO2 batteries that store grid energy take off globally

#32

Post by lambdaone »

cogman10 wrote: post #5
AndrewDucker wrote: post #2

No mention of round-trip efficiencies, and claims are that it's 30% cheaper than Li-Ion. Which might give it an advantage for a while, but as Li-Ion has become 80% cheaper in the last decade that's not something which will necessarily continue. Great if it can continue to be cheaper, of course. Fingers crossed that they can make it work at scale.

I'm seeing round trip efficiencies around 75%. That's not terrible. These things would probably pair well with district heating and cooling.

A theoretical study shows 77%, which is in the same ballpark: https://www.sciencedirect.com/science/article/pii/S136403212...

A few percent here of there is not that important if the input energy is cheap enough.

Re: CO2 batteries that store grid energy take off globally

#33

Post by buckle8017 »

So it's a compressed air facility but it's using dry CO2 because it makes the process easier and CO2 is cheap.

Not a carbon sequestration thing, but will likely fool some people into thinking it is.

So the question is, how much does it cost? The article is completely silent on this, as expected.

Re: CO2 batteries that store grid energy take off globally

#34

Post by lambdaone »

alexchamberlain wrote: post #18

Would this be effective at smaller volumes? Could it get down to say the size of a washing machine for use at home?

Very unlikely. All the technologies involved work best at scale; for example, the area-to-volume ratio of the liquid gas storage vessel is a critical parameter to keep energy losses low.

Re: CO2 batteries that store grid energy take off globally

#35

Post by lambdaone »

scotty79 wrote: post #13
AndrewDucker wrote: post #2

No mention of round-trip efficiencies, and claims are that it's 30% cheaper than Li-Ion. Which might give it an advantage for a while, but as Li-Ion has become 80% cheaper in the last decade that's not something which will necessarily continue. Great if it can continue to be cheaper, of course. Fingers crossed that they can make it work at scale.

Also sodium batteries are coming to the market at a fraction of the cost. "We’re matching the performance of [lithium iron phosphate batteries] at roughly 30% lower total cost of ownership for the system." Mukesh Chatter, cofounder and CEO, Alsym Energy

I see this as complementary to other energy storage systems, including sodium ion batteries; each will have its own strengths and weaknesses. I expect energy storage density cost will be the critical parameter here, as this looks best suited to do diurnal storage for solar power systems near out-of-town predictable power consumers like data centers.

Re: CO2 batteries that store grid energy take off globally

#36

Post by ben_w »

epgui wrote: post #29
creativeSlumber wrote: post #27

Earlier quoted context omitted.

Comparing it to X flights maybe correct from a greenhouse emissions standpoint, but extremely misleading from a safety perspective. A jet emits that co2 spread over tens of thousands of miles. The problem here is it all pooled in one location. Also that statement of 70 meters seem very off, looking at the size of the building. What leads to suffocation is the inability to remove co2 from your body rather than lack of…

It's a gas in an open space, it diffuses very quickly.

https://en.wikipedia.org/wiki/Limnic_eruption

I don't know the safety limits for this quantity, I hope the "70 meters" claim was by someone who modelled it carefully rather than a gut check.

Re: CO2 batteries that store grid energy take off globally

#37

Post by api »

zahlman wrote: post #12
lambdaone wrote: post #8

This seems almost too good to be true, and the equipment is so simple that it would seem that this is a panacea. Where are the gotchas with this technology? Clearly power capacity cost (scaling compressors/expanders and related kit) and energy storage cost (scaling gasbags and storage vessels) are decoupled from one another in this design; are there any numbers publicly available for either?

Well, it isn't going to sink enough CO2 to move the needle: > If the worst happens and the dome is punctured, 2,000 tonnes of CO2 will enter the atmosphere. That’s equivalent to the emissions of about 15 round-trip flights between New York and London on a Boeing 777. “It’s negligible compared to the emissions of a coal plant,” Spadacini says. People will also need to stay back 70 meters or more until the air clears,…

It’s a battery not a sequestration technology.

Re: CO2 batteries that store grid energy take off globally

#38

Post by to11mtm »

epgui wrote: post #29
creativeSlumber wrote: post #27

Earlier quoted context omitted.

Comparing it to X flights maybe correct from a greenhouse emissions standpoint, but extremely misleading from a safety perspective. A jet emits that co2 spread over tens of thousands of miles. The problem here is it all pooled in one location. Also that statement of 70 meters seem very off, looking at the size of the building. What leads to suffocation is the inability to remove co2 from your body rather than lack of…

It's a gas in an open space, it diffuses very quickly.

Yep. When I had to fill CO2 tanks at a paintball shop yes there were times that I had to open a door (I mean we were talking a lot of fills in short time, btw fills had to start with draining the tank's existing volume so I could zero out the scale) but even indoors a door+fan was enough to keep even the nastiest of sale days OSHA compliant.

Also a 'puncture' is very different from the gasbag mysteriously vanishing from existence; My only other thought is that in cold regions (I saw wisconsin mentioned in the article) CO2 does not diffuse quite as fast and sometimes visibly so...

Re: CO2 batteries that store grid energy take off globally

#39

Post by api »

to11mtm wrote: post #30
lambdaone wrote: post #8

This seems almost too good to be true, and the equipment is so simple that it would seem that this is a panacea. Where are the gotchas with this technology? Clearly power capacity cost (scaling compressors/expanders and related kit) and energy storage cost (scaling gasbags and storage vessels) are decoupled from one another in this design; are there any numbers publicly available for either?

I don't know numbers but I at least remember my paintball physics; As far as the storage vessel, CO2 has much lower pressure demands than something like, say, hydrogen. On something like a paintball marker the burst disc (i.e. emergency blow off valve) for a CO2 tank is in the range of of 1500-1800PSI [0]. A compressed air tank that has a 62cubic inch, 3000PSI capacity, will have a circumference of 29cm and a length…

So… it’s a compressed air battery but with a better working fluid than air.

I remember wondering about using natural gas or propane for this a long time ago. Not burning the gas but using it as a compressed gas battery. It liquifies easier than air, etc., but would be a big fire risk if there were leaks while this is not.

Seems neat.

Re: CO2 batteries that store grid energy take off globally

#40

Post by jaggederest »

creativeSlumber wrote: post #21

what happens if that large enclosure fails and the CO2 freely flows outside? That enclosure has a huge volume - area the size of several football fields, and at least 15 stories high. The article says it holds 2k tons of co2, which is ~1,000,000 cubic meters in volume. CO2 is denser than air will pool closer to the ground, and will suffocate anyone in the area. See https://en.wikipedia.org/wiki/Lake_Nyos_disaster Edi…

CO2 is in general less dangerous than inert gases, because we have a hypercapnic response - it's a very reliable way to induce people to leave the area, quite uncomfortable, and is actually one of the ways used to induce a panic attack in experimental settings.

If it were, say, argon, it would be much more likely to suffocate people, because you don't notice hypoxia the way you do hypercapnia. It can pool in basements and kill everyone who enters.

That being said it is an enormous volume of CO2, so the hypercapnic response in this case may not be sufficient if there's nowhere to flee to, as sadly happened in the Lake Nyos disaster you cited.

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