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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

#241

Post by danw1979 »

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?

The gotcha will be the “poor” round trip efficiency, in comparison to other storage technologies.

It’d be interesting to see if there’s any loss of efficiency with increasing storage duration too (relating to boil-off of the cryogenic side of the storage ?) because this would impact the economics of charging too.

I just get the feeling lithium/sodium ion for electricity and big piles of sand/dirt for heat are going to more-or-less win the energy storage race.

Re: CO2 batteries that store grid energy take off globally

#242

Post by rbanffy »

I have one concern: what if the container bursts? CO2 is heavier than air, and a sudden pressure decrease will cool it down further, so it'll hug the ground. What would be a safe distance for the people around the plant to live without the risk of being asphixiated in an accident?

Re: CO2 batteries that store grid energy take off globally

#243

Post by mschuster91 »

to11mtm wrote: post #41
cogman10 wrote: post #26

Earlier quoted context omitted.

In fact, the limiting element for Li chemistries is generally the Nickel. Pretty much everything else that goes into these chemistries is highly available. Even something like Cobalt which is touted as unavailable is only that way because the industrial uses of cobalt is basically only li batteries. It's mined by hand not because that's the best way to get it, but because that's the cheapest way to get the small amou…

> Even something like Cobalt which is touted as unavailable is only that way because the industrial uses of cobalt is basically only li batteries. AFAIR Cobalt is also kinda toxic which is a concern. But as far as that and > In fact, the limiting element for Li chemistries is generally the Nickel Isn't that part of why LiFePO was supposed to take off tho? Sure the energy density is a bit lower but theoretically they…

> Isn't that part of why LiFePO was supposed to take off tho? Sure the energy density is a bit lower but theoretically they are cheaper to produce per kWh and don't have any of the toxicity/rarity issues of other lithium designs...

LFP cells have long since taken off. Tesla has been making vehicles with LFP battery packs for half a decade now.

Re: CO2 batteries that store grid energy take off globally

#244

Post by ragebol »

rbanffy wrote: post #242

I have one concern: what if the container bursts? CO2 is heavier than air, and a sudden pressure decrease will cool it down further, so it'll hug the ground. What would be a safe distance for the people around the plant to live without the risk of being asphixiated in an accident?

The article mentions > 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, he says.

So: 70 meters

Re: CO2 batteries that store grid energy take off globally

#245

Post by lambdaone »

unsigner wrote: post #177

Peacetime technology from people who ignore the shooting war next door. Do you really want to build your energy system on huge soft targets? This looks much more vulnerable than solar arrays or battery installations to small-to-medium warheads (i.e anything from $500 FPV drones with an RPG round to $100k middle strike drones with 100 kg of payload).

It could be made much less vulnerable by dividing the gas storage balloon structures into a set of multiple smaller structures, ideally with some further internal partitioning so a single punctured surface does not release all the gas in that structure. Everything else is as 'hard' or 'soft' as any other piece of industrial plant, and can be hardened further by putting it inside a reinforced building or set of buildings, internal redundancy etc.

Re: CO2 batteries that store grid energy take off globally

#246

Post by gosub100 »

scoot wrote: post #230
usrusr wrote: post #216

I wonder how much Google is factoring in the implicit cooling cycle? Because any pressurized gas energy storage is either including some advanced heat storage or is just venting the heat created during compression (the ancient Huntorf facility in Germany is infamous for that, super wasteful) Usually you want to keep the heat and put it back into the compression medium during decompression and hope that losses from th…

Isn't this effectively neutral over time? Heat generated during compression, lost during decompression, so basically using the air as a heat storage medium?

I think what he's saying is you can boost efficiency if you compress a cooler gas. So if you could capture the "cold" that you get from discharging the device, and use it to pre-cool the air for the next cycle (or use it for the data centers cooling system) , it would be much more efficient.

Re: CO2 batteries that store grid energy take off globally

#248

Post by jvanderbot »

pkphilip wrote: post #247

Wasn't there a plan to use concrete blocks as energy storage medium by pulling them up a little bit at a time when there is surplus power?

Sure, some people have proposed that, but if you calculate how much has to be lifted to get 20 MW stored (or so), it gets pretty ridiculous pretty quickly. Like "Lift the largest aircraft carrier 20 meters" silly. You have some pretty severe size/mass issues.

It makes more sense to use water + a dam, but then again, we like to use water for things besides energy storage, and we're talking about a _lot_ of water.

This gas bag is effectively the same as water+dam, except the pressure is from the tanks and the compressor creates it, vs pumping uphill to create pressure.

Re: CO2 batteries that store grid energy take off globally

#249

Post by throwway120385 »

tor825gl wrote: post #213
catlikesshrimp wrote: post #179

Earlier quoted context omitted.

"litres-of-fuel per km-driven" (Volume/Distance) is still fully reductible to an area: litres is still a volume (1 cubic decimeter) and km is still a distance (1x10⁴ dm) Maybe you meant that the other way around? Distance/Volume (as in Miles/gallon) is an Area⁻¹ (Distance⁻²), which is more difficult to imagine in space. Now, Kg is a measure of mass (or weight, depending on who you are asking), which throws density in…

If you car was fueled by a fixed pipe which it travelled along, consuming all the fuel in the sections of the pipe that it moved past but no more, what would the cross section of the pipe be?

That's looking suspiciously like integration.

Re: CO2 batteries that store grid energy take off globally

#250

Post by gosub100 »

ragebol wrote: post #244
rbanffy wrote: post #242

I have one concern: what if the container bursts? CO2 is heavier than air, and a sudden pressure decrease will cool it down further, so it'll hug the ground. What would be a safe distance for the people around the plant to live without the risk of being asphixiated in an accident?

The article mentions > 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, he says. So: 70 meters

> or more

I guess it just depends on how much oxygen you really need.

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