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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

#301

Post by Hnrobert42 »

Animats wrote: post #54
Hnrobert42 wrote: post #23

Earlier quoted context omitted.

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…

Again, from TFA, the install needs 5 hectares of flat land. I thought it was odd when the article mentioned "flat" land, but I assumed it was more about accommodating the bubble. Now I am thinking it is specifically to avoid the valleys you are describing.

Re: CO2 batteries that store grid energy take off globally

#302

Post by eru »

catlikesshrimp wrote: post #179
eru wrote: post #173

Earlier quoted context omitted.

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 in…

> Now, Kg is a measure of mass (or weight, depending on who you are asking), which throws density into the equation, [...]

It's the other way round: chemically how much energy you get from burning your fuel is almost completely a function of mass, not of volume. (And in fact, you aren't burning liquid fuel either, in many engines the fuel gets vaporised before you burn it, thus expanding greatly in volume but keeping the same mass.)

> [...] which throws density into the equation, which is proportional to the temperature [...]

For an ideal gas, sure. But not for liquid fuels.

> "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.

I don't think that the reciprocal is a problem. No, what I mean is that you can't cancel fuel with driving. Litres-of-fuel is a different unit than distance-driven ^ 3. Similar to how torque and energy are different physical quantities that you can't cancel willy-nilly, despite their units looking similar.

You might find a physical interpretation for an adventurous cancelling, and that's fine. But that's because you are looking behind the raw unadorned units at the physics, and basing your decision on that.

Units are a very stripped down look at physics. So units working out are necessary for cancelling to make sense, but not sufficient.

Re: CO2 batteries that store grid energy take off globally

#304

Post by PunchyHamster »

adwn wrote: post #284
PunchyHamster wrote: post #278

Earlier quoted context omitted.

It's cute you think short cycles are somehow better in gas turbines and compressors and that you will restart the whole thing constantly to fill short term demands > In these discussions please keep in mind that frequency regulation, short term and long term shortage are different applications with different needs. The comparison is valid; If you want to fill hour to hour demand or add some frequency regulation, an i…

> It's cute you think […] Don't do that here.

Ignorant and patronizing answers get snark back.

But it's sad that you get triggered by snark and not... ignorance and/or lying

Re: CO2 batteries that store grid energy take off globally

#305

Post by scotty79 »

dzhiurgis wrote: post #296
scotty79 wrote: post #205

Earlier quoted context omitted.

That entirely depends on how large the market for stationary storage is going to be. On top of the price, sodium has advantage of being safer and usable in wider temperature range. Who in their right mind would pay 40% more to pick a dangerous and fussy product just because it's a bit smaller and lighter for their home?

Sodium is obviously better option even for cars in very cold climates (which is somewhat of a niche (tho lfp cold gates even in mild climates)) and IMO CATL et al will charge premium for this while they can. But initial claim was “fraction of the cost, tomorrow” which is super incorrect.

I did not say tomorrow. It will definitely take time.

What I'm opposing is flippantly relegating a new technology with real benfits, that the largest manufacturer of lithium batteries is significantly betting on, to the 0.01% of the market.

You say 0.01%, largest manufacturer of lithium batteries says 50%. If you meet half way it's still about 25% which is significant.

https://undecidedmf.com/why-the-biggest-battery-company-is-b...

Re: CO2 batteries that store grid energy take off globally

#306

Post by Ayanonymous »

I’m new to the idea of grid‑scale energy storage technologies, but this was a really clear and interesting introduction to how CO₂ batteries could help with long‑duration renewable energy storage. It’s exciting to see new approaches that might make solar and wind power more reliable and affordable. Thanks for sharing!

Re: CO2 batteries that store grid energy take off globally

#307

Post by nirvael »

wongarsu wrote: post #229
nirvael wrote: post #228

Earlier quoted context omitted.

I'm sort of thinking out loud here but could you have two batteries running simultaneously but on opposite cycles, so while one is cooling the other is heating? Obviously it wouldn't be 100% efficient but it might reduce some wasted energy.

The heat and cold are created by the compressing or decompressing the CO2 (our any other gas). If one battery is heating while the other needs heat that would imply that one is charging while the other discharges, which is rarely useful in normal operation

Yeah you're right I didn't think that through, why would you charge a battery while discharging another, just use the energy directly.

Re: CO2 batteries that store grid energy take off globally

#308

Post by unsigner »

pmontra wrote: post #286
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).

Customers will evaluate the risks. Thermal power plants are an easy target too, and oil and gas pipelines. And the oil tankers, according to the news of the last weeks. By the way, nobody cares about oil spills anymore. I guess all those ships were sailing empty /s

Of course they care about oil spills - this is why all the oil tankers in the last weeks were attacked when empty.

Re: CO2 batteries that store grid energy take off globally

#309

Post by dzhiurgis »

scotty79 wrote: post #305
dzhiurgis wrote: post #296

Earlier quoted context omitted.

Sodium is obviously better option even for cars in very cold climates (which is somewhat of a niche (tho lfp cold gates even in mild climates)) and IMO CATL et al will charge premium for this while they can. But initial claim was “fraction of the cost, tomorrow” which is super incorrect.

I did not say tomorrow. It will definitely take time. What I'm opposing is flippantly relegating a new technology with real benfits, that the largest manufacturer of lithium batteries is significantly betting on, to the 0.01% of the market. You say 0.01%, largest manufacturer of lithium batteries says 50%. If you meet half way it's still about 25% which is significant. https://undecidedmf.com/why-the-biggest-battery-…

Oh god, of course it's mr undecided. Go thru years of his hype videos and decide if ANY of his predictions were right. Goes well with EV viking and "just (don't) have a think".

Yes, eventually it might be 50%, but right now you can't even get _specs_ from CATL while LFPs are traded like commodity.

Re: CO2 batteries that store grid energy take off globally

#310

Post by westurner »

nine_k wrote: post #268
jakewins wrote: post #220

Earlier quoted context omitted.

> Energy Dome expects its LDES solution to be 30 percent cheaper than lithium-ion. Grid scale lithium is dropping in cost about 10-20% per year, so with a construction time of 2 years per the article lithium will be cheaper by the time the next plant is completed

Li-ion and even LFP batteries degrade; given a daily discharge cycle, they'll be at 80% capacity in 3 years. Gas pumps and tanks won't lose any capacity.

Lithium burns toxic. Carbon based solid-state batteries that don't burn would be safe for buses.

There are a number of new methods for reconditioning lithium instead of recycling.

Biodegradable batteries would be great for many applications.

You can recycle batteries at big box stores; find the battery recycling box at Lowes and Home Depot in the US.

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