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"In a renewable energy grid, batteries can handle about 80 percent of storage needs." Why couldn't you just add 25% more batteries?
It's not 25% more batteries. It's some 500% to 1000% more. But those would be used very few times.
Earlier quoted context omitted.
It's not 25% more batteries. It's some 500% to 1000% more. But those would be used very few times.
A system that can store 1000% more energy than what is possible with batteries could very well power the entire system. Thus eliminating the need for batteries for this purpose. It's always something that stuck out to me as an obvious point that few have noticed.
If your storing nearly free power for 9 months then having 40% round trip efficiency may not actually be a problem. But it’s terrible for daily storage as you would need roughly twice as many solar panels etc.
This is remarkably hard to follow. The actual technology at play here is bicarbonate-formate redox; as the linked paper states: >It is also clear that more integration between the disciplines of electrochemistry and heterogeneous catalysis is needed to overcome the challenges for advancing the HCO3−–HCO2− system as a feasible green alternative for storing and transporting energy. The idea of storing energy by convert…
I don't really have much understanding of chemistry. So possibly the most helpful part for me is the diagram with little trucks, the cost chart, and the paragraph below that says: "The electrochemical regeneration is not optimized...If the cell voltage could be reduced to 2 V and the faradaic efficiency raised to 80%, the total cost of hydrogen would be nearly cut in half...if the regeneration and reaction could be p…
Formate releases hydrogen differently:
HCOOH >> H2 + CO2
Other acids need an electron donor to produce hydrogen. Formate reduces itself.
>"If the regeneration and reaction could be performed at 8 M rather than 3 M concentration...", why can't they?
You're getting a little over my head here, but I think there might be some solubility problems.
>"If the cell voltage could be reduced" sounds super fishy to me; isn't that just a useless wish that the elements / molecules you're working with have different properties than they actually do?
The standard electrode potential does create a minimum voltage, but usually there is considerable inefficiency.
I can't answer the other questions, except to mention that formate is very stable and easy to store.
Earlier quoted context omitted.
A system that can store 1000% more energy than what is possible with batteries could very well power the entire system. Thus eliminating the need for batteries for this purpose. It's always something that stuck out to me as an obvious point that few have noticed.
Batteries have reasonably high round trip efficiency ~80%, where many proposed long term storage options are much much lower. If your storing nearly free power for 9 months then having 40% round trip efficiency may not actually be a problem. But it’s terrible for daily storage as you would need roughly twice as many solar panels etc.
Earlier quoted context omitted.
> If absoultely needed, the most obvious way to ship hydrogen is as methane. Methane has 2 problems: 1. it's a massive greenhouse gas if it leaks, 2. it requires CO2 to make, and in a decarbonized future that can only come from either biomass (limited) or DAC (expensive). You would either want ammonia or methanol. Ammonia does not have any of these problems, but it's very toxic. Methanol has the CO2 problem as well,…
It's not a greenhouse gas if you make it from atmospheric CO2, that's the whole point. Also, sending methane through a pipeline is pretty straightforward. Methanol is an option on the liquid side, but if you can make methanol from atmospheric CO2 and water, you can also make jet fuel, which will be needed as jet travel isn't really electrifiable.
What you likely mean is that when taking atmospheric CO2, burning methane does not cause additional CO2 emissions. However, that is orthogonal to the problem of methane itself as a greenhouse gas when it leaks (which by all experience it does regularly).
Earlier quoted context omitted.
Batteries have reasonably high round trip efficiency ~80%, where many proposed long term storage options are much much lower. If your storing nearly free power for 9 months then having 40% round trip efficiency may not actually be a problem. But it’s terrible for daily storage as you would need roughly twice as many solar panels etc.
You can build twice as many solar panels. It is making batteries that is problematic. Not to mention the argument supposes that the storage system must only output electricity, which is not necessarily the case.
If your alternative now needs massive amounts of solar panels just to charge it then suddenly it’s vastly more expensive. Also, both batteries and solar panels are bottlenecked by production capacity, so no you can’t just snap your fingers and have twice as many panels.
Also, deploying any other system at scale means ramping up production of that.
Earlier quoted context omitted.
It's not a greenhouse gas if you make it from atmospheric CO2, that's the whole point. Also, sending methane through a pipeline is pretty straightforward. Methanol is an option on the liquid side, but if you can make methanol from atmospheric CO2 and water, you can also make jet fuel, which will be needed as jet travel isn't really electrifiable.
That makes no sense. Methane has a global warming potential of around 28 over 100 years, meaning it causes 28x as much warming over that timeframe. It does not matter where the CO2 comes from. What you likely mean is that when taking atmospheric CO2, burning methane does not cause additional CO2 emissions. However, that is orthogonal to the problem of methane itself as a greenhouse gas when it leaks (which by all exp…
https://acp.copernicus.org/articles/22/9349/2022/
> "It is, however, very likely that hydrogen is emitted throughout the value chain, but it is unclear – given lack of data – which components contribute most and least to emissions."
Earlier quoted context omitted.
You can build twice as many solar panels. It is making batteries that is problematic. Not to mention the argument supposes that the storage system must only output electricity, which is not necessarily the case.
Batteries really aren’t problematic. EV’s need more batteries than the grid and there’s plenty of raw materials to cover global EV’s needs on top of this grid batteries have more options because they didn’t need portability or a 25 year lifespan etc. If your alternative now needs massive amounts of solar panels just to charge it then suddenly it’s vastly more expensive. Also, both batteries and solar panels are bottl…
I am merely pointing out that the battery part seems like an unnecessary component.
Earlier quoted context omitted.
Batteries really aren’t problematic. EV’s need more batteries than the grid and there’s plenty of raw materials to cover global EV’s needs on top of this grid batteries have more options because they didn’t need portability or a 25 year lifespan etc. If your alternative now needs massive amounts of solar panels just to charge it then suddenly it’s vastly more expensive. Also, both batteries and solar panels are bottl…
Those sound like excuses. FYI, a lot of the alternatives are things like pumped hydro which isn't that inefficient. Many situations just need heat at the end, and therefore don't need pure electricity. I am merely pointing out that the battery part seems like an unnecessary component.
That’s simply the reality and why there isn’t any long term grid storage, nothing is even close to viable when compared to batteries and extra generation.
Pumped hydro simply doesn’t scale. You can look at topographic maps and do some basic math but the vast quantities of water you would need simply don’t have enough locations to be viable. Worse, the fewer times you use that infrastructure the larger the payback you need when it’s actually in use.
Hydrogen is expensive, has terrible round trip efficiencies, dangerous to store, etc etc.
Earlier quoted context omitted.
Those sound like excuses. FYI, a lot of the alternatives are things like pumped hydro which isn't that inefficient. Many situations just need heat at the end, and therefore don't need pure electricity. I am merely pointing out that the battery part seems like an unnecessary component.
There are zero viable alternatives when you start talking TWh. That’s simply the reality and why there isn’t any long term grid storage, nothing is even close to viable when compared to batteries and extra generation. Pumped hydro simply doesn’t scale. You can look at topographic maps and do some basic math but the vast quantities of water you would need simply don’t have enough locations to be viable. Worse, the few…
And you're consistently ignoring the part about not everything needing electricity exclusively. Any sort of heat utilization or recapture massively increases efficiency for some of those ideas.