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

#211

Post by tgsovlerkhgsel » Sun, Sep 26, 2021, 7:58 PM UTC

ordu wrote: post #178

tgsovlerkhgsel wrote: post #173

Earlier quoted context omitted.

> Current SF6 level (...) accounts for 10% of heat forcing. Source? This does not match what https://en.wikipedia.org/wiki/IPCC_list_of_greenhouse_gases says. In my naive mind, Methane seems like the it could be a good candidate for removal from atmosphere: If you could just get it to react with oxygen, it turns into water and the much less harmful CO2, so you don't have to sequester anything, and the reaction is exo…

Do you suggest releasing a catalyst into atmosphere? It may be dangerous, people tend to release methane, kids sometimes injure themselves by "catalysing" reaction of methane with oxygen by a flame source just for fun of watching flame farts. It would be unfortunate if these flame farts happened spontaneously as a sort of an embarassing social accident.

I was thinking more of pumping air across a surface coated with a catalyst. Although a releasable catalyst would also be an interesting option. Not sure if flame farts would be a hindrance or a feature.

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

#212

Post by ruffrey » Mon, Sep 27, 2021, 7:01 PM UTC

tito wrote: post #73

ruffrey wrote: post #60

Earlier quoted context omitted.

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?

I've been looking for a way to make a dent in climate change, while also eking out a living.

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

#213

Post by dredmorbius » Tue, Sep 28, 2021, 11:36 AM UTC

Animats wrote: post #97

It's a clickbait title, like the "fuel from water" people and the "hydrogen economy" people. Yes, with enough energy you can crack hydrocarbons out of combustion products. This is only useful if you have plenty of energy but it's not in a portable form suitable for rockets. As a means of removing CO2 from Earth's atmosphere, it's hugely inefficient. If you have that much electricity around, use the electricity, don't…

There are applications, particularly in certain modes of transporation, in which electrification is difficult. Batteries are heavy and large. Extension cords can only be made so long.

Even in a world in which heavier-than-air flight is sharply curtailed, there's still an exeptionally strong case to be made for marine transport as the most efficient mode huamns have ever developed, in moving mass a given distance with a given energy input (ton-miles/gallon or tonne-km/litre as you prefer).

Large, long-distance, high-capacity aircraft will require some sort of liquid fuel. Hydrocarbons have high density by both volume and mass, are well-understood, are remarkably non-toxic and non-volatile (for fuels), and have excellent handling and storage characteristics.

Marine shipping has similar constraints. Wind might re-emerge as a partial contributor. Solar might aid in auxiliary electrical systems. But a big slow marine deisel or turbine remains a hugely efficient prime mover. Solid fuels (e.g., pelletised wood waste) is an option, but is still strongly inferior to liquid fuels.

Even for rail, electrification of heavy freight is a challenge, all the more so with elevation gain and loss, and when travelling far from infrastructure. Yes, much European freight rail is electrified, but it operates at a much smaller scale and through far more developed regions than US and Canadian railways. The need to electrify an entire route also poses challenges (though rail does somewhat lend itself to incremental enhancement).

Electric rocketry is a whole 'nother challenge. Very long extension cords, maybe? Is Musk working on those?