The real question for me isn't the physics so much as ops over 20–30 years: maintenance, leakage, real-world efficiency after thousands of cycles
CO2 batteries that store grid energy take off globally
221–230 of 320 posts
Re: CO2 batteries that store grid energy take off globally
#222I wonder how much Google is factoring in the implicit cooling cycle? Because any pressurized gas energy storage is either including some advanced heat storage or is just venting the heat created during compression (the ancient Huntorf facility in Germany is infamous for that, super wasteful) Usually you want to keep the heat and put it back into the compression medium during decompression and hope that losses from th…
If Google is colocating these with data centers, even low-grade heat that would otherwise be a loss could still be useful, or at least reduce how much active cooling the DC needs
Re: CO2 batteries that store grid energy take off globally
#223>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…
Even if sodium-ion really gets to $10–20/kWh, you still have degradation, cycle limits, fire risk, and a practical lifetime that's maybe 10–15 years
Re: CO2 batteries that store grid energy take off globally
#224Earlier quoted context omitted.
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.
GP wasn't talking about discharge, losing a little energy, they were talking about wear and tear, as in the batteries aging fast while in a highly charged state.
Battery recycling still hasn't really left the "we can do it in a lab" stage.
Re: CO2 batteries that store grid energy take off globally
#225No 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.
I agree with you: the real test isn't whether it's 30% cheaper today, but whether it holds its economics over 20–30 years at scale
Re: CO2 batteries that store grid energy take off globally
#226This seems almost too good to be true, and the equipment is so simple that it would seem that this is a panacea. Where are the gotchas with this technology? Clearly power capacity cost (scaling compressors/expanders and related kit) and energy storage cost (scaling gasbags and storage vessels) are decoupled from one another in this design; are there any numbers publicly available for either?
The funniest part is that the "implicit cooling cycle" might be more valuable for grid alignment than raw efficiency
Re: CO2 batteries that store grid energy take off globally
#227I 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…
Here's a quote I got for a solar install in the Philippines this week: 51.2v 314ah cells (15kwh battery) 16x 580-590w solar panel Installed for 310k PHP = $5,275 I've also specced out 15-16kwh batteries using the Yxiang design for around the price of your Solix. The problem in the US is regulatory and a particularly predatory tradesman market at the moment.
Is that "regulatory" the problem or is it the solution? We'll know more 20 years from now, looking back at fire incident statistics.
(yes, I'm leaving it open if regulation makes a difference or not - for all we know it could even make a negative difference, helping companies that are better at regulation than at safety. But if I had to bet, I know where my money would be)
Re: CO2 batteries that store grid energy take off globally
#228I wonder how much Google is factoring in the implicit cooling cycle? Because any pressurized gas energy storage is either including some advanced heat storage or is just venting the heat created during compression (the ancient Huntorf facility in Germany is infamous for that, super wasteful) Usually you want to keep the heat and put it back into the compression medium during decompression and hope that losses from th…
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.
Re: CO2 batteries that store grid energy take off globally
#229I wonder how much Google is factoring in the implicit cooling cycle? Because any pressurized gas energy storage is either including some advanced heat storage or is just venting the heat created during compression (the ancient Huntorf facility in Germany is infamous for that, super wasteful) Usually you want to keep the heat and put it back into the compression medium during decompression and hope that losses from th…
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
Re: CO2 batteries that store grid energy take off globally
#230I wonder how much Google is factoring in the implicit cooling cycle? Because any pressurized gas energy storage is either including some advanced heat storage or is just venting the heat created during compression (the ancient Huntorf facility in Germany is infamous for that, super wasteful) Usually you want to keep the heat and put it back into the compression medium during decompression and hope that losses from th…
Isn't this effectively neutral over time? Heat generated during compression, lost during decompression, so basically using the air as a heat storage medium?