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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

#171

Post by tomas789 »

mannyv wrote: post #137

I have two solar panels that can generate around 960w/hr. Both panels cost around $400 ($200x2). Cheap. Storing that energy is quite expensive. an Anker Solix 3800, which is around 3.8kwh, costs $2400 USD. To store 10kwh would cost $7200 USD (which gets us more than 10kwh). If that cost asymmetry can come down then it becomes feasible to use solar power to provide cheap/local electricity in poor countries at a house…

The batteries in MWh range cost around 160 EUR/kWh all in. Including grid connection and BOP.

Re: CO2 batteries that store grid energy take off globally

#172

Post by tirant »

Waterluvian wrote: post #117
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... ]—…

If 1 watt is 1 joule per second then, honestly, what are we doing with watt-hours? Why can’t battery capacity be described in joules? And then charge and discharge being a function of voltage and current, could be represented in joules per unit time. Instead its watt-hours for capacity, watts for flow rate. Watt-hours… that’s joules / seconds * hours? This is cursed.

Don’t stay there: EVs are even reporting consumption in terms of kWh/100km or kWh/100miles instead of just average kW.

Re: CO2 batteries that store grid energy take off globally

#173

Post by eru »

selcuka wrote: post #153
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…

True. Otherwise we would be using square meters for measuring gas mileage instead of miles-per-gallon (or litres-per-km) [1]. [1] https://what-if.xkcd.com/11/

Well, if you want to be pedantic, it's litres-of-fuel per km-driven. That doesn't cancel as nicely, if you don't drop the annotations.

Arguably, we should probably use kg-of-fuel (or mol) instead of litres-of-fuel anyway.

Re: CO2 batteries that store grid energy take off globally

#175

Post by Gud »

jaggederest wrote: post #40
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 basement…

CO2 is extremely dangerous in high concentrations because the body reacts and switch off the breathing.

Re: CO2 batteries that store grid energy take off globally

#176

Post by ekr »

tirant wrote: post #172
Waterluvian wrote: post #117

Earlier quoted context omitted.

If 1 watt is 1 joule per second then, honestly, what are we doing with watt-hours? Why can’t battery capacity be described in joules? And then charge and discharge being a function of voltage and current, could be represented in joules per unit time. Instead its watt-hours for capacity, watts for flow rate. Watt-hours… that’s joules / seconds * hours? This is cursed.

Don’t stay there: EVs are even reporting consumption in terms of kWh/100km or kWh/100miles instead of just average kW.

What people care about when talking about EVs and consumption is generally how much distance they can cover. If you take away the distance factor and just report power, it becomes meaningless/almost useless.

Re: CO2 batteries that store grid energy take off globally

#177

Post by unsigner »

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).

Re: CO2 batteries that store grid energy take off globally

#178

Post by Jean-Papoulos »

>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 what's the actual advantage of this ? I think it's just lucky to land just at the right time where batteries aren't cheaper enough yet.

Re: CO2 batteries that store grid energy take off globally

#179

Post by catlikesshrimp »

eru wrote: post #173
selcuka wrote: post #153

Earlier quoted context omitted.

True. Otherwise we would be using square meters for measuring gas mileage instead of miles-per-gallon (or litres-per-km) [1]. [1] https://what-if.xkcd.com/11/

Well, if you want to be pedantic, it's litres-of-fuel per km-driven. That doesn't cancel as nicely, if you don't drop the annotations. Arguably, we should probably use kg-of-fuel (or mol) instead of litres-of-fuel anyway.

"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 into the equation, which is proportional to the temperature, which will vary according to where and when the driving takes place. But since the time and place, and hence the temperature is (allegedly) defined when the fuel consumption was tested, the density is a constant, and as such you can leave it out from the relation.

Mass = V*ρ

(I know, I am being pedantic² :)

Re: CO2 batteries that store grid energy take off globally

#180

Post by [deleted] »

TrainedMonkey wrote: post #43
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.

AFAIK cost here counts only the manufacturing side. While your conclusion that in the long run economies of scale will prevail, the lifetime costs are probably more than 30%. For example I expect recycling costs to be significantly worse for the Li-Ion.

[deleted]
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