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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

#291

Post by jakewins »

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.

These are LCOE numbers we are comparing, so that is factored in.

The fact that pumps, turbines, rotating generators don’t fail linearly doesn’t mean they are not subject to wear and eventual failure.

Re: CO2 batteries that store grid energy take off globally

#292

Post by whimsicalism »

nayuki wrote: post #290
whimsicalism wrote: post #283

Earlier quoted context omitted.

I think it is generally polite to flag when you are using an LLM to write your comment, some people tire of reading the same style of writing over and over - even if the content of your comment is interesting!

Oh good point; I wouldn't have noticed if you didn't point it out. The last ~5 comments from yoan9224 are all in 4-paragraph format. A few comments before that are in 3-paragraph format. They all look suspiciously uniform in writing style, and very mechanical.

frankly for me it stands out even reading this single comment. the classic it’s not X it’s Y + “what’s missing from the article” (basically a flashing neon sign). perhaps that’s why i get so annoyed by these comments, they’re just a stylistic monoculture which gets tiresome very quickly.

Re: CO2 batteries that store grid energy take off globally

#293

Post by mrspuratic »

audunw wrote: post #218
PunchyHamster wrote: post #192

Earlier quoted context omitted.

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

Pumped hydro is just not a valid comparison. I wish people would understand that already… it’s only good for long term storage in certain key geographical regions. Its use case is very limited. You don’t want to used pumped hydro for short term storage because the rapid cycling will drive up the maintenance costs. You actually hear about hydro power plants talking about installing batteries to reduce wear. In these d…

Ireland is lucky enough to have several suitable sites, but just one operational: Turlough Hill, which has been running for over 50 years and is in use daily. It's at least as useful in terms of grid stability and (relatively) rapid dispatch as capacity. Output ~0.7% of total daily (~120GWh), ~5% of daily peak (~6GW), wintertime figures. For comparison electricity usage has increased about 8-fold since it was deployed in 1974.

Re: CO2 batteries that store grid energy take off globally

#294

Post by perlgeek »

pfdietz wrote: post #88
perlgeek wrote: post #87

Earlier quoted context omitted.

We need every approach that's viable. Batteries are part of the solution, and will be in future. But I don't see why we we should assume they're better in every way than this approach

A principle in engineering is that for any market niche, only a few, or even one, technology persists. The others are driven to extinction as they can't compete. It's the equivalent of ecology's "one niche, one species" principle. There are far more technologies going for the hours scale storage market than will survive. Sure, explore them. But expect most to fail to compete.

The definition of "market niche" must do too much work for my liking to make this true.

For example, for the market niche "getting people from one location to another" there are quite many technologies, like walking, bicycles, scooters, cars, trains, ships, airplanes, helicopters etc., none of them evolved as a clear winner that displaced the others.

You might say, that's a whole market, not just a market niche, but it's also a niche of the larger transportation market.

When we look at something like grid-scale energy storage, how do we know if it's a winner-takes-all niche? Maybe constraints such as availability of space, availability of funding, weather, climate, grid demands etc. create sub-niches with their own winners. Or maybe not, but how can we known?

Re: CO2 batteries that store grid energy take off globally

#295

Post by thescriptkiddie »

alwa wrote: post #74
thescriptkiddie wrote: post #57

Earlier quoted context omitted.

The tanks to hold liquid CO2 will likely be a lot cheaper than compressed air tanks because the required pressure is much lower. But they are going to loose a lot of energy to cooling the gas and reheating the liquid. I would be surprised if the round-trip efficiency is higher than 25%.

They claim 75% efficiency AC-AC [0], and they point out that there’s no degradation with time. What estimates are you using to arrive at the 25% figure? [0] https://energydome.com/co2-battery/

i didn't do any math tbh, i just took the 25% number from the wikipedia page for cryogenic energy storage. i assumed their efficiency would be lower of the smaller temperature differential, but maybe it will be higher because they are storing part of the energy as pressure rather than temperature

Re: CO2 batteries that store grid energy take off globally

#296

Post by dzhiurgis »

scotty79 wrote: post #205
dzhiurgis wrote: post #110

Earlier quoted context omitted.

It's not panacea. Only lithium vs sodium is cheaper and they can use lower grade graphite which is just slightly cheaper (overall 30% reduction). Rest is same while it's a new manufacturing process. Meanwhile 99.99% production is focused and will be continued focused LFP.

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.

Re: CO2 batteries that store grid energy take off globally

#297

Post by thescriptkiddie »

upofadown wrote: post #85
thescriptkiddie wrote: post #57

Earlier quoted context omitted.

The tanks to hold liquid CO2 will likely be a lot cheaper than compressed air tanks because the required pressure is much lower. But they are going to loose a lot of energy to cooling the gas and reheating the liquid. I would be surprised if the round-trip efficiency is higher than 25%.

The energy used to liquefy the CO2 is the bulk of the energy stored. They don't throw it away afterwards. The the liquid-gas transition is why this works so much better than compressed air.

of course they are not throwing the energy away. but by using a working fluid that changes phase they are trading away energy efficiency for power density, for the same reason that steam engines are less efficient than stirling engines.

Re: CO2 batteries that store grid energy take off globally

#298

Post by hvb2 »

while_true_ wrote: post #270
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... ]—…

California found out pumped hydro isn't so "tried and true" when it was shut down during a drought due to lack of water behind the dam.

Not every area is as messed up as the Colorado river watershed...

All users (states) were given an allotment which, when it was set, was more than what would ever be the yearly supply.

From the outset it was essentially a free for all. Everyone was happy, they kinda got what they asked. It's just that they were all living in a paper reality

Re: CO2 batteries that store grid energy take off globally

#299

Post by LikeBeans »

cenamus wrote: post #259
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

Good point. I was thinking more about areas without much water and a large field of poles each hoisting several blocks. Sort of wind turbines but without the blades.

Re: CO2 batteries that store grid energy take off globally

#300

Post by GuB-42 »

Waterluvian wrote: post #282
GuB-42 wrote: post #279

Earlier quoted context omitted.

1 Wh = 3600 Ws = 3600 J It is not more cursed than km/h (1 m/s = 3600 m/h = 3.6 km/h) Both those units are more convenient than their SI equivalent and their "cursedness" come from the hour/minute/second time division. If we had decimal time, as it was initially proposed with the metric system, we wouldn't have this problem, but we weren't ready to let go of hours/minute/second.

Yeah. I get this is all kind of silly. I think what trips me up is that a watt doesn’t represent a timeless amount of something the way a meter does. A watt involves a unit amount of time. Imagine if the distance between you and I was 438 kiloflerp-hours. And to get to you in one hour I have to drive at a speed of 438 kiloflerps. It works, it kinda makes sense. It just feels inconsistent with all the other units I wo…

For me, one of the most cursed unit, but not because it is ill-conceived is the Nm (the unit of torque).

It is analogous to the Joule, but it doesn't mean the same thing. "This car has a 250 million ft.lb battery and 0.1 Wh of torque" passes dimensional analysis.

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