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Engineers are developing new ways to convert greenhouse gases to fuel

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

#161

Post by tgsovlerkhgsel »

amelius wrote: post #136
mlindner wrote: post #80

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

> The hard part is getting the CO2 out of the atmosphere in the first place. From the article: The Martian atmosphere is composed almost entirely of carbon dioxide.

The article is trying to "sell" the technology for two use cases, Mars and climate change mitigation on Earth.

For Mars, the process being inefficient, expensive, slow etc. isn't necessarily a big hurdle as it competes with shipping fuel all the way from Earth, while on Earth, it has to compete with a lot of easily available alternatives.

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

#162

Post by henearkr »

The big progress to watch is rather the new process to catalyse CO2 hydrates formation from CO2 at sea floor conditions [1].

What we really need is capture and store CO2, not capture and release again...

[1] https://phys.org/news/2021-09-metals-supercharge-method-carb...

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

#163

Post by henearkr »

throwawayboise wrote: post #72
hannob wrote: post #50

Earlier quoted context omitted.

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.

No, these leaks are of serious concern.

This was one of the reasons behind the recent scandal where "blue hydrogen" had been found to be very dirty.

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

#164

Post by __MatrixMan__ »

lizknope wrote: post #156
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…

I don't disagree with anything you said but the article claims they are turning CO2 into fuel which the ISS is NOT doing.

Agreed. Reaction mass != Fuel

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

#165

Post by tgsovlerkhgsel »

CodeGlitch wrote: post #118
mlindner wrote: post #80

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

This I do not understand... why do we not build a nuclear reactor out in the middle of no-where - easily accessible via shipping - that has the job of taking CO2 out of the atmosphere, and converting into liquid methane? It can run 24/7. Little running costs? No one complaining about NIMBYISM.

Removing CO2 from the atmosphere ("direct air capture") is currently extremely expensive and inefficient, compared to e.g. getting it from some other industrial process or the exhaust from a fossil fueled plant. And you still end up having to ship the fuel which isn't trivial.

Nuclear power is currently more expensive per kWh than renewables. This could potentially change if we were to build many identical plants, which would be viable with this strategy. By building it somewhere far from civilization, lower safety standards could also become acceptable, lowering cost further.

But in order for this to pay off, you'd need an absolutely massive investment, and I suspect nobody wants to take that risk. Building 100 nuclear power plants will be cheaper than building one per plant but still more expensive in absolute numbers, and each plant is already a many-billion project. So for this to work, you'd likely need someone to commit hundreds of billions, and most likely all upfront/at the same time to actually reap the cost benefits for the nuclear plants. And the technology to actually make use of the power isn't there yet.

OTOH, with solar and wind, you can build a plant at basically any scale. A lot of small projects is much easier to make happen than one absolutely gargantuan one.

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

#166

Post by henearkr »

fho wrote: post #111
gpm wrote: post #85

Earlier quoted context omitted.

Yes, and sort of. The ISS is constantly losing gas, I believe that the primary source of new O2 is actually electrolysis of water, not pressurized tanks, but that they do also have pressurized tanks as a backup. A person breathes out roughly 1kg of CO2/day, and it follows you breathe in about the same amount of O2, not an impossible amount of mass to resupply.

> 1kg of CO2/day which is crazy low if you put it in perspective and see that (gas powered) cars release about 0.2 kg of CO2 ... per kilometer.

Seems very low expressed like that, but actually it isn't because when you take your car you typically drive tens of kilometers.

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

#167

Post by tgsovlerkhgsel »

CodeGlitch wrote: post #137
Manuel_D wrote: post #134

Earlier quoted context omitted.

It'd be much, much, more effective to hook up a nuclear reactor to the grid to take fossil fuel plants offline, and avoid releasing CO2 in the first place. Though in the long term, it might be useful to do what you propose to produce carbon neutral hydrocarbon fuel for things that need exceptional energy density. Like air travel or space launch vehicles.

> Though in the long term, it might be useful to do what you propose to produce carbon neutral hydrocarbon fuel for things that need exceptional energy density. Like air travel or space launch vehicles. Yes that's what I had in mind - thanks. I do remain sceptical that electric cars will save us. If everyone buys an electric car, and then plugs them in the evening to charge - I'm not sure the grid will cope very well…

Why would they plug them in the evening though? If you're using the car, you're likely to be parking it at a place with a high car density (e.g. a large parking garage or an employer's parking lot), where chargers can be deployed cheaply.

If you have a short commute, you might also not care how fully charged your car is as long as it is enough. So you may specify that you want a state of charge of 50-80% at the end of the day, and the grid can decide when to charge your car. It won't be enough to smooth out all the fluctuations in renewable generation, but it surely will help.

10 million cars (~20% of the cars existing in Germany) attempting to charge is at least 10 GW of load that can be shed when necessary, and significantly more than that in load that you can sink when there is excess power (I'm assuming each car needs to charge e.g. 10 kWh over 10 hours). Wikipedia says the total Regelleistung (operating reserve?) in Germany is 12.5 GW (7 GW in one direction, 5.5 in the other) and that this is responsible for 40% of the cost of the grid fees.

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

#168

Post by tgsovlerkhgsel »

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

Wow. I didn't realize that this is such a huge space. I thought Climeworks was basically the only company that actually has a working product already.

Is there a way to invest into the space through some form of managed fund? I have no way of evaluating the economics of any of the companies, but would like to park some of my money by investing in this sector (both hoping for an at-least-comparable-to-market return and wanting to support the development of the technology, while being OK with accepting extra risk - basically, I'm willing to donate to carbon capture and sequestration in the form of accepting a worse point than other investments on the risk/reward curve).

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

#169

Post by tito »

tgsovlerkhgsel wrote: post #168
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

Wow. I didn't realize that this is such a huge space. I thought Climeworks was basically the only company that actually has a working product already. Is there a way to invest into the space through some form of managed fund? I have no way of evaluating the economics of any of the companies, but would like to park some of my money by investing in this sector (both hoping for an at-least-comparable-to-market return an…

Stay tuned, there's a contact form for the fund: https://launchpad.airminers.org/fund

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

#170

Post by tito »

sailingparrot wrote: post #78
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

Great resource, we pull from it for the AirMiners Boot Up as well.

BTW people can access all the Boot Up content on your own on the "Content" menu: https://bootup.airminers.org/meeting-1

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