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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

#191
post #75
post #51

Earlier quoted context omitted.

It has nothing whatsoever to do with sinking CO2.

I understand this, but it coincidentally uses CO2 and it's hard for me to understand why the technology would sound "too good to be true" without imagining such a purpose.

It's a one-time "use" though, it's not consuming CO2, so it's not going to move any needle

Re: CO2 batteries that store grid energy take off globally

#192

>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…

If it is barely cheaper than lithium, it's much more expensive than traditional pumped storage.

Yeah, it's expensive to build, but then cheap to run for decades.

It's nice that we explore alternatives but this just seems like investor bait

Re: CO2 batteries that store grid energy take off globally

#193
post #172

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.

Heh. To borrow an idea from xkcd (measuring gas consumption as area): The kWh measures energy, right? And energy is force times distance. So energy divided by distance is force! Let’s all start measuring EV consumption in newtons, folks. It even makes intuitive sense: It correlates well with how hard you need to push the car to get it going at the usual travel speed. But it sucks if you need to figure out how far you can travel on a given charge.

Re: CO2 batteries that store grid energy take off globally

#194

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.

Yep, it's stupid from a units consistency pov. A bit like using calories instead of joules. But on the other hand we also use hours for measuring time instead of kiloseconds...

Yeah, if only we would define seconds to be 13.4% shorter than that are, we could have 100ks days. Also, ksecs would be a really convenient unit for planning one's day: a ~15 minute resolution is just right for just about any type of appointment.

Oh, and 1Ms weeks, consisting of 7 working days and 3 off days sound nice too.

One can dream! :-)

Re: CO2 batteries that store grid energy take off globally

#195

As always, diversity in the energy ecosystem is a huge plus. Time and time again we see that 'one size fits all' is simply not true so I'm a fan of alternative approaches that use completely different principles. This enables the energy ecosystem to keep exploring the space of possibilities efficiently. I hope this continues to be developed.

> Time and time again we see that 'one size fits all' is simply not true Do we though? It feels like we're still in the stage where we're just trying to figure out what the best solution is for grid-scale storage, but once we do figure it out, the most efficient solution will win out over all the others. Yes, there may be some regional variation (e.g. TFA mentions how pumped hydro is great but only makes sense where…

The point I was making isn't that we are or aren't actually narrowing down our options, it is that diversity of options is important. We have artificially limited diversity in our energy ecosystem and the rapid adoption of solar/wind/etc shows that. We could have been here decades ago if we actually encouraged diversity and exploration of alternate energy instead of actively discouraging it. Now that it is impossible to hold wind/solar back they are dominating. We should learn from that and encourage exploring diverse options in storage. Luckily I don't think storage has nearly the pushback that generation has had so I think it will be easier for many options to enter and find their niche.

Re: CO2 batteries that store grid energy take off globally

#196
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…

Western storage options are very expensive.

We are starting to see Chinese options pop up but not sure if I would install them yet.

https://www.docanpower.com/eu-stock/zz-48kwh-50kwh-51-2v-942...

Re: CO2 batteries that store grid energy take off globally

#197
post #77

We don't need another few-hours storage technology. Batteries are going to clobber that. What we need is a storage technology with a duration of months. That would be truly complementary to these short term storage technologies.

We need anything that scales quickly, safely, and cheap. Just getting us through the duck curve would be a tremendous win for energy. https://en.wikipedia.org/wiki/Duck_curve

Batteries already solve that.

https://blog.gridstatus.io/caiso-solar-storage-spring-2025/

Re: CO2 batteries that store grid energy take off globally

#198

Earlier quoted context omitted.

Yep, it's stupid from a units consistency pov. A bit like using calories instead of joules. But on the other hand we also use hours for measuring time instead of kiloseconds...

Yeah, if only we would define seconds to be 13.4% shorter than that are, we could have 100ks days. Also, ksecs would be a really convenient unit for planning one's day: a ~15 minute resolution is just right for just about any type of appointment. Oh, and 1Ms weeks, consisting of 7 working days and 3 off days sound nice too. One can dream! :-)

Much better to make seconds slightly larger than 2 seconds, and move to a dozenal system throughout. One hour is (1000)_12 novoseconds. A semi-day is (10000)_12.

Oh, we should switch our standard counting system to dozenal a well.

Re: CO2 batteries that store grid energy take off globally

#199

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.

Batteries aren’t really suited for seasonal storage - they decay when fully charged. And foreseeable future they provide such huge value for grid stability that it wouldn’t make sense economically either.

lithium yearly discharge is in single digit %, what a nonsense argument.

Re: CO2 batteries that store grid energy take off globally

#200
post #77

We don't need another few-hours storage technology. Batteries are going to clobber that. What we need is a storage technology with a duration of months. That would be truly complementary to these short term storage technologies.

Hell, even week will do a lot, you can start importing energy from areas that have currently better renewables conditions over night, even preemptively for a period of bad weather
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