Making more methane seems like a risky option, given its role in climate change.
this post was submitted on 11 Jul 2024
33 points (94.6% liked)
Green Energy
2194 readers
119 users here now
everything about energy production
founded 2 years ago
MODERATORS
This is great in theory, but all it really does is give us a reason to cling onto a dirty, leaky natural gas grid. Much like CCS, this technology allows fossil fuel producers to continue business as usual under the promise of one day maybe sortof going green, and if this system leaks much more than ~1%, its not actually "carbon neutral" in useful human timescales, because its converting CO2 into something 50-100x more impactful on the climate
If it can be done cheaper this way than extracted via drilling (fracking) wells, then it's a pure win because it will displace the activity that increases CO2 and the vast majority of Methane leaks while the transition to other technologies occurs. It would be a tremendous benefit in terms of eliminating the acceleration of greenhouse effects.
If it can be done cheaper this way...
That "if" is doing a lot lot of heavy lifting, and exactly the excuse a lot of fossil fuel companies and municipalities will use for inaction.
If it can't be cost effective it won't happen. It won't slow down solar or other green house gas emission neutral options. I'm not rooting for that scenario.
That's the thing, it doesn't have to happen. It has to catch enough headlines that Shell can say:
"As part of our environmental commitments we plan to sell only carbon neutral methane by 2040"
Then they proceed to do nothing in the "hopes" that this becomes cost effective in time, while continuing to invest in natural gas infrastructure, and while we continue to investing in using their "soon to be neutral" fuel.
Finally, when 2035 or so rolls around they quietly shift the goal posts and we keep on letting them pollute.
And if you're wondering why this sounds familiar...
https://www.carbonbrief.org/shell-abandons-2035-emissions-target-and-weakens-2030-goal/
All getting hyped about CCS or "renewable" "drop-in replacements" for fossil fuels does is further entrench fossil fuel companies as the "center" of our carbon commitments, while they are 100% disincentivized to act.
Unless this tech is paired with a $1000/tonne carbon tax, its a scapegoat.
We don't need Shell to install solar arrays. Thinking that the companies that are causing the problem will fix it for us is what will delay indefinitely any solution. Being able to synthesize methane or not has no influence on whether or not a carbon tax is appropriate. Greenhouse gass emission taxes are appropriate under either circumstance.
How would you feel if those fossil fuel producers stopped extracting fossil methane and instead were producing methane from atmospheric CO2 and fossil free energy?
Batteries are 90% or better efficiency
Unless this process has a similar efficiency, not sure how useful it will be.
Furthermore, presumably the methane will be used to generate heat.
Heat pumps are 500% efficient and induction is also highly efficient
Gas appliances are not...
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.
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
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... https://www.energy.gov/fecm/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.
That's correct. Electro-chemical storage is not limited by the Carnot efficiency limit like combustion engines are. Conversion losses should be a huge factor in choosing energy storage.
The fertilizer that's propping up our unsustainable factory farming is created using the Faber process that turns methane and nitrogen into ammonia. Food prices are lower because methane is cheap as a byproduct of oil refining. It might be cool to instead take carbon out of the atmosphere and then convert it into fertilizer to grow plants that remove even more carbon from the air.
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. There will also be methane leaks in the system too, so you will lose more.
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. Fuel cell engines overall are only 60% 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 anyone want to use gas heaters? With heat pumps, you pour in 1kwh of energy, and get 5kwh of heat. With Gas heating, you pour in 1kwh of gas, and maybe get 0.9kwh of energy (or at best 0.97). You CAN'T get better than 1kwh
-
Why would you want to store it like oil? Oil is 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..
Oh, you are aussie:) i should have guessed by your username.
Ok, for starters, where I live that big yellow thing stops shining. Practically (for electricity production anyways) for almost 6 months of the year and almost totally for 3. And even with heat pumps we still use several MWh of electricity every year to heat our homes. A battery park can keep a city running for 1h. Even those planned in NSW (BESS is it?) would struggle to keep things running for mire than a day. To be clear:
We need more energy storage than can be provided by electric batteries, than can be bought at battery prices and in scales larger than can be produced with any technology current or in the overseeable future. And we needed it yesterday. Any form of low cost, stable, easy to store solution we can use is a huge step forward. Solar is great! But we need the electricity when the sun doesn't shine. Heat pumps are awesome! But their awesomness is needed when the sun doesn't shine so much. That is why we need more energy storage solutions.
Summertime there are almost limitless electricity available, but that energy needs to be stored somehow. And with limitless (in practice) efficiency isn't an issue. Even storing 1% is better than 0%. Regardless of efficiency.