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CO2 batteries that store grid energy take off globally

spectrum.ieee.org

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Re: CO2 batteries that store grid energy take off globally

#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.

Re: CO2 batteries that store grid energy take off globally

#5

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.

Re: CO2 batteries that store grid energy take off globally

#6

Does pure-ish CO2 have advantages over regular air or the freon-like substance used in air conditioning? How much energy us used to purify and maintain the CO2?

It's pretty cheap to acquire a boatload of and, assuming you don't get it directly from burning fossil fuels, there's really no environmental harms of it leaking into the atmosphere. [1]

[1] https://en.wikipedia.org/wiki/Carbon_capture_and_storage

Re: CO2 batteries that store grid energy take off globally

#7

Does pure-ish CO2 have advantages over regular air or the freon-like substance used in air conditioning? How much energy us used to purify and maintain the CO2?

It's easy to liquefy, so it has a density advantage over air, and would be bad if released but not super bad.

Re: CO2 batteries that store grid energy take off globally

#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?

Re: CO2 batteries that store grid energy take off globally

#9

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.

Lithium supply is limited. So an alternative based on abundant materials is interesting for that reason I guess?

Re: CO2 batteries that store grid energy take off globally

#10
post #6

Does pure-ish CO2 have advantages over regular air or the freon-like substance used in air conditioning? How much energy us used to purify and maintain the CO2?

It's pretty cheap to acquire a boatload of and, assuming you don't get it directly from burning fossil fuels, there's really no environmental harms of it leaking into the atmosphere. [1] [1] https://en.wikipedia.org/wiki/Carbon_capture_and_storage

> CCS could have a critical but limited role in reducing greenhouse gas emissions.[6] However, other emission-reduction options such as solar and wind energy, electrification, and public transit are less expensive than CCS and are much more effective at reducing air pollution. Given its cost and limitations, CCS is envisioned to be most useful in specific niches. These niches include heavy industry and plant retrofits.[8]: 21–24

> The cost of CCS varies greatly by CO2 source. If the facility produces a gas mixture with a high concentration of CO2, as is the case for natural gas processing, it can be captured and compressed for USD 15–25/tonne.[66] Power plants, cement plants, and iron and steel plants produce more dilute gas streams, for which the cost of capture and compression is USD 40–120/tonne CO2.[66]

... And then for this usage, presumably you'd have to separate the CO2 from the rest of the gas.

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