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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

#51

Post by dmd »

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 has nothing whatsoever to do with sinking CO2.

Re: CO2 batteries that store grid energy take off globally

#52

Post by Smoosh »

laurencerowe wrote: post #46

> Energy Dome expects its LDES solution to be 30 percent cheaper than lithium-ion. Can see how this could scale up for longer storage fairly cheaply but on current trends batteries will have caught up in cost in 2-3 years.

Aren’t CATL already producing sodium-ion batteries for about 60% the cost of lithium-ion for equivalent capacity?

Re: CO2 batteries that store grid energy take off globally

#53

Post by apparent »

ben_w wrote: post #36
epgui wrote: post #29

Earlier quoted context omitted.

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.

Seems like it would depend if there was a small tear or a massive breach.

Re: CO2 batteries that store grid energy take off globally

#54

Post by Animats »

Hnrobert42 wrote: post #23
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…

The last section of TFA is called "What happens if the dome is punctured?". The answer: a release of CO2 equal to about 15 transatlantic flights. People have to stand back 70m until it clears. It would not be good, but it wouldn't be Bhopal. And there are still plenty of factories making pesticides.

> People have to stand back 70m until it clears.

How did they calculate that evacuation distance? CO2 is heavy. That little house about 15m from the bubble needs to be acquired.

The topography matters. If the installation is in a valley, a dome rip could make air unbreathable, because the CO2 will settle at the bottom. People have been killed by CO2 fire extinguishing systems. It takes a reasonably high concentration, a few percent, but that can happen. They need alarms and handy oxygen masks.

Installations like this probably will be in valleys, because they will be attached to wind farms. The wind turbines go in the high spots and the energy storage goes in the low spots.

Re: CO2 batteries that store grid energy take off globally

#55

Post by gpm »

cogman10 wrote: post #28
Tade0 wrote: post #15

Earlier quoted context omitted.

There are over 200 billion tonnes of lithium in seawater, it's just the least economical out of all sources of this element. There are plenty more, but they're explored only when there's a price hike.

AFAIK, the brine pits are pretty economical, they just require ocean access. What I'm somewhat surprised about is that we've not seen synergies with desalination and ocean mineral extraction. IDK why the brine from a desalination plant isn't seen as a prime first step in extraction lithium, magnesium, and other precious minerals from ocean water.

> What I'm somewhat surprised about is that we've not seen synergies with desalination and ocean mineral extraction.

I think these guys are basically using desalination tech to make lithium extraction cheaper: https://energyx.com/lithium/#direct-lithium-extraction

As I understand it (which is far from perfectly) it's still not using ocean water, because you can get so much higher lithium concentration in water from other sources. But it's a more environmentally friendly, and they argue cheaper, way to extract the lithium from water than just using the traditional giant evaporation pools.

Re: CO2 batteries that store grid energy take off globally

#56

Post by to11mtm »

buckle8017 wrote: post #33

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.

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

Honestly considering the design overall, I feel like one could make a single use science project version of this on a desk (i.e. aside from the CO2 recharging part) for under 200 bucks. 12oz CO2 tank, some sort of generator and whatever you need to spin it that is sealed, tubing, and a reclamation bag for the used CO2.

And IMO using CO2 makes the rest of the design cheaper; Blow off valves are relatively cheap for this scenario, especially because CO2 gas system pressures are fairly low, and there's plenty of existing infrastructure around the safety margin. And I think even with blow off valves this could be a 'closed' system with minimal losses (although that would admittedly add to the cost...)

I guess I'm saying is the main unknown is how expensive this regeneration system is for the quoted efficiency gains.

Re: CO2 batteries that store grid energy take off globally

#57

Post by thescriptkiddie »

buckle8017 wrote: post #33

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.

The tanks to hold liquid CO2 will likely be a lot cheaper than compressed air tanks because the required pressure is much lower. But they are going to loose a lot of energy to cooling the gas and reheating the liquid. I would be surprised if the round-trip efficiency is higher than 25%.

Re: CO2 batteries that store grid energy take off globally

#58

Post by hawk_ »

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.

"I am seeing" as in do you use CO2 batteries at home or something?

Re: CO2 batteries that store grid energy take off globally

#59

Post by [deleted] »

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…

[deleted]

Re: CO2 batteries that store grid energy take off globally

#60

Post by laurencerowe »

Smoosh wrote: post #52
laurencerowe wrote: post #46

> Energy Dome expects its LDES solution to be 30 percent cheaper than lithium-ion. Can see how this could scale up for longer storage fairly cheaply but on current trends batteries will have caught up in cost in 2-3 years.

Aren’t CATL already producing sodium-ion batteries for about 60% the cost of lithium-ion for equivalent capacity?

Yeah. Maybe this tech will have a place for week-long storage and be a good buffer for wind power but I hard to see the economics working for daily cycling.
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