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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

#251

Post by yohannparis »

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.

Different solutions for different needs.

It's good for engineers and planners to have multiple solutions available that provide better fit to their prerogatives and needs.

We don't need one solution to do it all. We need plural ones.

Re: CO2 batteries that store grid energy take off globally

#252

Post by HPsquared »

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?

If a car gets 50 mpg (UK gallons), the fuel consumption is equivalent to a circular string of diameter 0.27 mm.

Re: CO2 batteries that store grid energy take off globally

#253

Post by LikeBeans »

I wonder how does it compare to hoisting a concrete (or something heavy) block up a pulley system as an energy store? When you need the energy you let it slide down pulling some steel cable that turns a generator, or multiple cables into multiple generators. Or even a cascade of concrete blocks at different heights as a space saver.

Re: CO2 batteries that store grid energy take off globally

#255

Post by api »

pfdietz wrote: post #78
api wrote: post #39

Earlier quoted context omitted.

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.

Except you have to trap and recycle the uncompressed CO2, hence that enormous bag to hold all that gas. Color me skeptical. With compressed air, you just release the air back to the atmosphere.

They mention that and say it fits in a huge inflatable tent, which rings true. CO2 is more dense than nitrogen and oxygen which are most of air, and if you're storing it at ambient pressure you don't need a super strong vessel.

Re: CO2 batteries that store grid energy take off globally

#256

Post by sowbug »

LikeBeans wrote: post #253

I wonder how does it compare to hoisting a concrete (or something heavy) block up a pulley system as an energy store? When you need the energy you let it slide down pulling some steel cable that turns a generator, or multiple cables into multiple generators. Or even a cascade of concrete blocks at different heights as a space saver.

The article does address that.

...and even dangling heavy objects in the air and dropping them. (The creativity devoted to LDES is impressive.) But geologic constraints, economic viability, efficiency, and scalability have hindered the commercialization of these strategies.

Re: CO2 batteries that store grid energy take off globally

#257

Post by heisenbit »

thekoma wrote: post #165
nayuki wrote: post #109

> The tried-and-true grid-scale storage option—pumped hydro [--> https://spectrum.ieee.org/a-big-hydro-project-in-big-sky-cou... ], in which water is pumped between reservoirs at different elevations—lasts for decades and can store thousands of megawatts for days. > Media reports show renderings of domes but give widely varying storage capacities [--> https://www.bloominglobal.com/media/detail/worlds-largest-co... ]—…

Power plants are often described in terms of (max) power output, i.e., contribution to the grid. So, I can see how it might confuse a writer to then also talk about storage inadvertently. But also, the second paragraph already describes the 100 MWh vs MW nuance.

It is not a nuance in an article that focuses on storage from the supposed premier professional association. As an engineer I would expect typical energy content (median/average) of the top 10 hydro pump projects and also some discussion about the availability of suitable sites. I think one should strive for at least high school level physics. There is no need to push out texts that can be easily surpassed by any current llm.

Re: CO2 batteries that store grid energy take off globally

#258

Post by charlieo88 »

tor825gl wrote: post #215
svpk wrote: post #143

Earlier quoted context omitted.

I believe it's just a matter of intuitively useful units. There's simply too many seconds in a day for people to have an immediate grasp on the quantity. If you're using a space heater or thinking about how much power your fridge uses kilowatt hours is an easy unit to intuit. If you know you have a battery backup with 5 kilowatt hours of capacity and your fridge averages 500 watts then you've got 10 hours. If you con…

There are two types of jobs, the ones which require you to know that a day is about 8.5x10^5 seconds, and those which don't.

Is this sarcasm?

Re: CO2 batteries that store grid energy take off globally

#259

Post by cenamus »

LikeBeans wrote: post #253

I wonder how does it compare to hoisting a concrete (or something heavy) block up a pulley system as an energy store? When you need the energy you let it slide down pulling some steel cable that turns a generator, or multiple cables into multiple generators. Or even a cascade of concrete blocks at different heights as a space saver.

Probably extremely poorly, as that's basically pumped hydro on _tiny_ scale. The amount of mass/water that fits into storage lakes is insane

Re: CO2 batteries that store grid energy take off globally

#260

Post by yogurtboy »

Perseids wrote: post #207
Jean-Papoulos wrote: post #178

>The company uses pure, purpose-made CO2 instead of sourcing it from emissions or the air, because those sources come with impurities and moisture that degrade the steel in the machinery. So no environmental advantages. It's supposedly 30% cheaper than lithium-ion, but BYD cars have sodium-based based batteries on the road right now which CATL says will end up being 10-20$/kwh (10x cheaper than current batteries). So…

To cite and expand on lambdaone below [1]: > 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 Lambdaone is differentiating between the costs to store energy (measured in kWh or Joules) and the costs to store energy per time (which is power , measured in Watts). If you want to store th…

What an excellent explanation, thanks
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