Comment on Capturing CO2 With Copper, Scientists Generate 'Green Methane'
Auzy@beehaw.org 2 months ago
Batteries are 94% or better efficiency
Unless this process has a similar efficiency, not sure how useful it will be.
Batteries may be more efficient, but we can’t use them to store all the energy we need. And heat pumps still need electricity when there is less renewable electricity available.
Looking at nature, long carbon chains are the way to store lots of energy and being able to use just electricity to get carbon out of the air is a great first step. Capturing the methane will allow us to process it further.
This is the best news regarding energy storage I’ve seen in a long time.
Why can’t we use batteries? There’s no reason we can’t given all the battery chemistries available including chemistries which are still undiscovered.
As you said, it’s really just energy. And if this process is only 75% efficient, and then using it is 75%, it’s a waste of a huge amount of energy.
I’d we’re just going to burn it and put it back in the air, it’s not a solution at all… We’re just replacing one greenhouse gas with one that is just as bad
If you have excess oil you build a really cheap metal container to put it in. If you have extra energy to go into the battery to need to spend the full amount to make a new battery to store it.
It’s fixed cost vs marginal cost. Marginal cost of oil storage is pretty low
Yes… Sure, its cheap to set up…
Great at periods when you have lots of extra solar/renewables.
But… if the efficiency is low, a potentially worse solution for the rest of the year (like Winter), because any excess you can generate, will mostly be lost.
Furthermore, you’ll need a way to convert it back into electricity. In the future, they’re aiming for 60% efficiency for Gas Power Plants… energy.gov/…/how-gas-turbine-power-plants-work . At the moment apparently its much less
So 60% * 0.85 = 50% efficiency… AND THAT IS OPTIMISTIC AND DETERMINANT ON FUTURE TECH!
So you lose half of the power you store. Which means you’re replacing the money you spend on batteries… on more power generation anyway…
They definitely have some utility when there is insufficient battery as a final backup. They may also be useful in applications which don’t use power too and in some utilities which use the gas directly. It also is still centralised power generation, so rural areas will still be unreliable…
But, I’d prefer they deploy Vanadium Redox Flow batteries instead as they’re 75-90% efficient.
You said it yourself. Still undiscovered. The technology we have today can’t be used to save more than a day or so of electricity. We need to handle months. Finding more energy dense ways of doing it is crucial.
And even if we burn it and put it back in the air, it is still positive, because we won’t have added more from oil. And if we get enough of the stuff we can let the trees grow, which would be a carbon sink.
Step 1: stop using oil. If we use the methane as is, we’ve accomplished this step. Step 2: scrub carbon from atmosphere. Upping the game and replacing wood for heating would let the trees scrub the atmosphere, creating carbon sinks Step 3: accelerate. Can processed methsne be stored in energy dense compounds? Like oil was?
That makes no sense…
Australia keeps less than 21 days of petrol of all types. Why would we need to store months? This seems like one of those silly arguments where it’s assumed incorrectly that the sun stops shining and the wind stops blowing (which only happens in limited locations).
And when I say including undiscovered, I mean its only getting better. For grid energy storage, energy density isn’t an issue. Energy density is ONLY an issue for transportation and phones. We just need to scale up the technology now, and thats already rapidly happening.
This entire thing comes down to efficiency at the end of the day. The efficiency of the conversion here is 85%, and you still need to convert it back into energy (which is hugely inefficient). Even if converting it back to energy is 75% efficient (it’s likely not), that’s only 64% efficient.
Batteries are 94%. Even Vanadium Redox Flow is 75-90%. There’s plenty of low density low cost efficient batteries (especially now Sodium batteries are available)
Also…
“If we use methane as is, we’ve accomplished this” - You can’t just swap current products with methane… Even if you did, petrol engines are totally inefficient. We’re likely talking not even talking 50% efficient
“Replacing wood for heating”. We already HAVE a solution for heating. Burning methane is less than 100% efficient max. Heat pumps are already at 500% efficiency and the efficiency is growing.
Why would you want to store it like oil? It’s incredibly toxic… And, burning it is inefficient.
This has it’s applications, but its likely more competing with Hydrogen, NOT batteries. Also, this is still a research paper, not a commercial product. By the time it’s commercial, batteries might be 50% cheaper again…
Dyf_Tfh@lemmy.sdf.org 2 months ago
This could be useful for making synthetic aviation fuel at scale. Need methane + hydrogen + lot of energy.
Copper is abundant compared to the other rare earth catalysts, thus reducing cost.
Auzy@beehaw.org 2 months ago
This makes more sense than the other response. But…
(I have a pilot licence for light aircraft)
The reality is that engines for aviation suck. They’re loud, they’re inefficient and expensive to operate.
You also need very high octane fuel on any real planes.
They also rely on oxygen and require a lot of maintenance. Most light aircraft can’t take off at higher altitudes for that reason (you need turboprops)
You also have to contend with balancing fuel tanks and blocked fuel air vents and a lot of hardware like magnetos.
Startup checks are also a pain.
Also, even bad electric motors tend to be highly responsive and high torque and can be used to regenerate power during descent
it’s fairly common for the startup checks to fail because there is excess oil you need to burn off fouling the spark plugs (but you can simply increase the power).
Because the tanks are so big too, water can condense inside, so you need to check the fuel for contamination constantly
I think a lot of pilots are looking forward to moving away from avgas. The only advantage currently for fuel is energy density by weight and refueling time. But there is no reason they couldn’t battery swap in the future or improve batteries