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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

#121

Post by ajb »

mark-r wrote: post #94
ajb wrote: post #17

Earlier quoted context omitted.

These days CO2 is actually quite commonly used in air-conditioners as a refrigerant, R-744. Fluorinated gases like Freon are being phased out due to being even worse for global warming.

I thought it was ozone depletion, not greenhouse effects, that led to the fluorinated gas phaseout?

The original ones yes. They are already banned - but the next generation of fluorinated refrigerants are apparently ok for the ozone layer but have a greenhouse effect. That's my understanding anyway, I'm far from an expert.

Edited to add: https://en.wikipedia.org/wiki/Kigali_Amendment has some information on this.

Re: CO2 batteries that store grid energy take off globally

#122

Post by B1FF_PSUVM »

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.

It's easier to figure out for people that measure power in watts and time in hours ... 1 kW for 1 hour is 1 kWh.

That camel's nose was already in the tent with the mAh thing in phone/etc batteries, now with electric vehicles we're firmly in kWh land.

Not to mention that's what the power utilities used all along ...

Re: CO2 batteries that store grid energy take off globally

#123

Post by kumarvvr »

pfdietz wrote: 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.

> What we need is a storage technology with a duration of months

Actually, having expandable, highly re-usable tech like this is much better when the capacities are in terms of hours.

This storage, combined with say 2.5x solar panel installation, could essentially provide power at 1x day and night.

Re: CO2 batteries that store grid energy take off globally

#125

Post by kumarvvr »

thescriptkiddie wrote: post #57
buckle8017 wrote: post #33

So it's a compressed air facility but it's using dry CO2 because it makes the process easier and CO2 is cheap. Not a carbon sequestration thing, but will likely fool some people into thinking it is. So the question is, how much does it cost? The article is completely silent on this, as expected.

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%.

Heat from compression is stored in a thermal energy storage system. Most likely something like a sand container.

Re: CO2 batteries that store grid energy take off globally

#126

Post by pfdietz »

kumarvvr wrote: post #123
pfdietz wrote: 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.

> What we need is a storage technology with a duration of months Actually, having expandable, highly re-usable tech like this is much better when the capacities are in terms of hours. This storage, combined with say 2.5x solar panel installation, could essentially provide power at 1x day and night.

Yes, and we have that. It's called Li-ion batteries.

Re: CO2 batteries that store grid energy take off globally

#127

Post by SigmundA »

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.

A watt of power multiplied by a second of time has an agreed upon name called joule, but a watt second is also a perfectly valid SI name.

A watt is a joule of energy divided by a second of time, this is a rate, joule per second is also a valid name similar to nautical mile per hour and knot being the same unit.

Multiplication vs division, quantity vs rate, see the relationship? Units may have different names but are equivalent, both the proper name and compound name are acceptable.

A watt hour is 3600 joules, it’s more convenient to use and matches more closely with how electrical energy is typically consumed. Kilowatt hour is again more directly relatable than 3.6 megajoules.

Newton meter and Coulomb volt are other names for the joule. In pure base units it is a kilogram-meter squared per second squared.

Re: CO2 batteries that store grid energy take off globally

#128

Post by kumarvvr »

pfdietz wrote: post #126
kumarvvr wrote: post #123

Earlier quoted context omitted.

> What we need is a storage technology with a duration of months Actually, having expandable, highly re-usable tech like this is much better when the capacities are in terms of hours. This storage, combined with say 2.5x solar panel installation, could essentially provide power at 1x day and night.

Yes, and we have that. It's called Li-ion batteries.

They are good for about 1000 cycles.

This system can run for decades.

Re: CO2 batteries that store grid energy take off globally

#129

Post by pfdietz »

kumarvvr wrote: post #128
pfdietz wrote: post #126

Earlier quoted context omitted.

Yes, and we have that. It's called Li-ion batteries.

They are good for about 1000 cycles. This system can run for decades.

Utility-scale Li-ion batteries are good for an order of magnitude more than that.

"LFP chemistry offers a considerably longer cycle life than other lithium-ion chemistries. Under most conditions, it supports more than 3,000 cycles; under optimal conditions, more than 10,000 cycles."

https://en.wikipedia.org/wiki/Lithium_iron_phosphate_battery...

Re: CO2 batteries that store grid energy take off globally

#130

Post by hkt »

B1FF_PSUVM wrote: post #115
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... ]—…

> big yikes for something coming out of the Institute of Electrical and Electronics Engineers. Besides the unit flub, there's an unpleasant smell of sales flyer to the whole piece. Hard data spread all over, but couldn't find efficiency figures. Casual smears such as "even the best new grid-scale storage systems on the market—mainly lithium-ion batteries—provide only about 4 to 8 hours of storage" (huh, what, why?).…

I'm sat here thinking: why not compressed or liquefied air?
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