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Engineers are developing new ways to convert greenhouse gases to fuel

uc.edu

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Re: Engineers are developing new ways to convert greenhouse gases to fuel

#71

Post by throwawayboise »

dotancohen wrote: post #63
jl6 wrote: post #54

Earlier quoted context omitted.

To be clear, the solution to climate change is first to stop burning fossil fuels, and then to start removing carbon from the atmosphere. This technology won’t help long term removal of carbon if we just burn the resulting fuel, but it might help displace fossils as a source for some applications that would otherwise be at the very end of the fossil ramp-down.

There still must be some input of energy. From what I understand, the Sabatier reaction is really only viable from an environmental perspective if it is powered by some other non-carbon energy, such as solar or wind.

Yes, to convert CO2 to CH4 you need to break the C-O bonds. This takes energy.

Re: Engineers are developing new ways to convert greenhouse gases to fuel

#72

Post by throwawayboise »

hannob wrote: post #50
bialpio wrote: post #12

I wish they addressed the fact that methane that they will be producing is said to be an even more potent greenhouse gas than carbon dioxide. Are there any worries about the leakage for example?

This is an important point. Not for the "we'll build a gas station on mars"-scenario, but for the "we'll propose this as a climate solution". Every way of replacing natural gas with some other source of methane - be it the sabatier process or biogas/biomethane - has this problem. It can only be a climate solution if you can bring leaks down close to zero, which is very challenging. It also makes one wonder whether e-…

Methane is produced naturally in vast quantities by decaying organic matter, cow farts, released from volcanoes, natural reservoirs, etc. I doubt that some small leaks in an industrial process would make a real difference. It would probably be undetectable in comparison to the leaks in our current natural gas infrastructure that we use for heating homes, cooking, and electrical generation.

Re: Engineers are developing new ways to convert greenhouse gases to fuel

#73

Post by tito »

ruffrey wrote: post #60
tito wrote: post #57

For anyone starting a carbon removal startup, check out AirMiners http://airminers.org For anyone who has been scouring the web to learn about carbon removal and wants all the best stuff in one place, check out the 5-week AirMiners Boot Up http://bootup.airminers.org

Thank you so much for sharing this! Exactly what I've been looking for.

Sure thing! For a bit of customer interview, can you describe your process so far to this point? Where have you been looking, what got you interested, etc. And when you say "exactly what you were looking for", what are you seeing?

Re: Engineers are developing new ways to convert greenhouse gases to fuel

#74

Post by gpm »

dexwiz wrote: post #47
gpm wrote: post #24

Earlier quoted context omitted.

The ISS uses rechargeable zeolite beds for CO2 scrubbing, they don't need a new one frequently, and the fact that we shipped a new one is coincidence. Zeolite is a mineral, you get a bunch of small pellets of it in a bed, and run air over it while cooling it. The CO2 (and H2O) stick to it while everything else goes over it. Once you're at capacity you vent it to space and heat it, the CO2 (and H2O) leave the bed (int…

If both operations are exothermic, why the heat exchanger? I would assume one process would need to be endothermic.

Fixed the typo

Re: Engineers are developing new ways to convert greenhouse gases to fuel

#75

Post by DennisP »

marginalia_nu wrote: post #29
realusername wrote: post #17

Earlier quoted context omitted.

Thermodynamics is about energy not CO2, you can design negative CO2 devices and we even have proof in nature of that since that's what trees are doing.

The problem is that this requires reversing entropy. Turning CO2 into something that can burn into CO2 requires more energy than you get back while burning it, even in an optimal engine. This is true if humans reverse entropy or if trees do it.

It's not an energy source, it's a battery.

Re: Engineers are developing new ways to convert greenhouse gases to fuel

#76

Post by rale00 »

eganist wrote: post #10

I'm less interested in this as a climate change remedy (it's not) and more interested in this for its terraforming potential. What are the benefits and risks from just bleeding spare methane into the atmosphere after any refueling reservoirs are topped off? I'd think it'd be useful in raising temperatures on the planet, though that's only one terraforming component. (I'm very dangerously not an expert on this)

Methane is fairly short-lived in the atmosphere, at only 12 years, so it probably wouldn't be particularly effective at terraforming mars. Perfluorocarbons or sulfur hexafluoride can stick around for thousands of years, so they would probably be a better place to start.

Re: Engineers are developing new ways to convert greenhouse gases to fuel

#77

Post by jerf »

mirekrusin wrote: post #36

We just need long pipe from Earth to Mars to pump out CO2 there. It has to be long in case it gets entangled with the Sun. The best is to fund it from crypto tokens. Winning Elon's XPrize should buy few km of McDonald's straws to kick it off.

For giggles: A 3 square-foot pipe from here to Mars at Mars' closest point of approach would hold about 31.7 million metric tons of CO2 at atmospheric pressure [1], which looks to be about 2 day's worth of US emissions.

[1]: https://www.google.com/search?q=38.6+million+miles+*+3+feet%...

Re: Engineers are developing new ways to convert greenhouse gases to fuel

#78

Post by sailingparrot »

tito wrote: post #57

For anyone starting a carbon removal startup, check out AirMiners http://airminers.org For anyone who has been scouring the web to learn about carbon removal and wants all the best stuff in one place, check out the 5-week AirMiners Boot Up http://bootup.airminers.org

Or if you would rather do it on your own time I can recommand the CDR Primer: https://cdrprimer.org/read

Re: Engineers are developing new ways to convert greenhouse gases to fuel

#79

Post by colordrops »

mrguyorama wrote: post #65
colordrops wrote: post #20

Earlier quoted context omitted.

Agreed that the future is electrification, but it will take trillions of dollars and a lot of time to replace all internal combustion engines. What should we do in the meantime? It seems that using renewable energy to make carbon neutral fuels for these vehicles makes a lot of sense. What is "nonsense" about this?

It would take more time, energy, money, and resources to build out enough solar and wind (etc) to turn enough CO2 into enough fuel for all our cars than it takes to just replace the cars with electric ones and use that massive solar and wind grid to just power them straight

It's not all or nothing, and further more the electricity from solar and wind is fungible and can be used for either fuel generation or direct usage by electric cars, so it would serve us either way, no matter how long it took.

These things are not contradictory. We can build out more renewable electricity supply, replace with electric cars, and generate carbon neutral fuel all at the same time. You are underestimating how long and difficult the ICE replacement is going to take. It's not like a single organization can just wave a wand and all gas cars would be replaced over night.

Re: Engineers are developing new ways to convert greenhouse gases to fuel

#80

Post by mlindner »

Converting CO2 into fuell isn't the hard part. The hard part is getting the CO2 out of the atmosphere in the first place.

We've known how to convert CO2 into fuel since the end of the 19th century.

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

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