Engineers are developing new ways to convert greenhouse gases to fuel • Hacker News Board

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

#11

Post by jl6 » Fri, Sep 24, 2021, 5:06 PM UTC

throwaway894345 wrote: post #2

The actual title is "UC reactor makes Martian fuel" and the subtitle is "A gas station on Mars? Engineers envision the possibilities." But the submission title is "UC reactor converts carbon dioxide to fuel to address climate change"? While it does talk about applications with respect to carbon capture, if we consume the fuel byproduct, presumably we just end up with co2 in the atmosphere? > “In the future we’ll deve…

> if we consume the fuel byproduct, presumably we just end up with co2 in the atmosphere?

The process would still be great news if true, as it could be a carbon-neutral source of hydrocarbon fuel for applications that are hard to electrify, like aviation.

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

#12

Post by bialpio » Fri, Sep 24, 2021, 5:06 PM UTC

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?

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

#13

Post by lizknope » Fri, Sep 24, 2021, 5:07 PM UTC

The article claims they are already converting CO2 to fuel on the ISS. This process has been TESTED but we aren't using it right now.

Article claims:

> Known as the “Sabatier reaction” from the late French chemist Paul Sabatier, it’s a process the International Space Station uses to scrub the carbon dioxide from air the astronauts breathe and generate rocket fuel to keep the station in high orbit.

Reality:

We just shipped a new CO2 scrubber a few months ago

https://www.nasa.gov/centers/marshall/news/releases/2021/mar...

For LONG space missions or colonies

https://www.eni.com/en-IT/scientific-research/space-free-co2...

The ISS is constantly falling back to earth. It maintains its orbit with thrusters on the Zvezda module or a visiting spacecraft boosts it higher

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

#14

Post by canadaduane » Fri, Sep 24, 2021, 5:08 PM UTC

I wish this article spent more time on the science.

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

#15

Post by yholio » Fri, Sep 24, 2021, 5:12 PM UTC

No, enough with this nonsense. Capturing, liquefying and transforming CO2 into fuel requires energy - due to thermodynamic limits, much more energy than what the fuel can give back. You then take that fuel, and... burn it into 25% efficient engines that spew the very same CO2 back into the air, along with some new carcinogenic fumes and acid-rain inducing nitrogen oxides?

No, just no, full stop. They way forward is electrification of everything, using only carbon-neutral energy, renewables &nuclear. No hydrogen, no methane, no electric to fuel, let's not do these physical stupidities to keep dying industries alive.

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

#16

Post by whatshisface » Fri, Sep 24, 2021, 5:13 PM UTC

whatever1 wrote: post #9

I like how in the media publications for carbon capturing they always forget to mention that these things need a ton of energy to run.

If people were willing to work through the issues with nuclear power, running a bunch of nuclear plants to power the scrubbers would be semi-reasonable.

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

#17

Post by realusername » Fri, Sep 24, 2021, 5:13 PM UTC

yholio wrote: post #15

No, enough with this nonsense. Capturing, liquefying and transforming CO2 into fuel requires energy - due to thermodynamic limits, much more energy than what the fuel can give back. You then take that fuel, and... burn it into 25% efficient engines that spew the very same CO2 back into the air, along with some new carcinogenic fumes and acid-rain inducing nitrogen oxides? No, just no, full stop. They way forward is e…

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.

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

#18

Post by btilly » Fri, Sep 24, 2021, 5:13 PM UTC

This isn't the only team trying this. See https://www.universityofcalifornia.edu/news/making-methane-m... for another team working on the same thing for the same purpose.

It is worthy of note that the process that is described is exactly the one that Elon Musk was already planning to use on Mars. This is exactly why finding water on Mars is critical to his plans, and is also why Starship is designed to run on methane-oxygen. (Starship will be the second methane rocket ever. And the first, Starhopper, used the same raptor engine.)

It is also worth pointing out that producing methane here on Earth for use around Earth is not particularly helpful. Methane is hard to store and is a better greenhouse gas than carbon dioxide. Then if you use it for a rocket, you put that carbon dioxide back in the atmosphere. We benefit a bit from the shade provided by the water vapor so it isn't quite net neutral, but it is pretty close.

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

#19

Post by wyager » Fri, Sep 24, 2021, 5:15 PM UTC

realusername wrote: post #17

yholio wrote: post #15

No, enough with this nonsense. Capturing, liquefying and transforming CO2 into fuel requires energy - due to thermodynamic limits, much more energy than what the fuel can give back. You then take that fuel, and... burn it into 25% efficient engines that spew the very same CO2 back into the air, along with some new carcinogenic fumes and acid-rain inducing nitrogen oxides? No, just no, full stop. They way forward is e…

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.

There are several conceptual issues here, but one of them is that trees require energy from sunlight to turn CO2 into other things.

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

#20

Post by colordrops » Fri, Sep 24, 2021, 5:16 PM UTC

yholio wrote: post #15

No, enough with this nonsense. Capturing, liquefying and transforming CO2 into fuel requires energy - due to thermodynamic limits, much more energy than what the fuel can give back. You then take that fuel, and... burn it into 25% efficient engines that spew the very same CO2 back into the air, along with some new carcinogenic fumes and acid-rain inducing nitrogen oxides? No, just no, full stop. They way forward is e…

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?