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Engineers find neat way to turn waste carbon dioxide into useful material

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Re: Engineers find neat way to turn waste carbon dioxide into useful material

#31

Post by pm90 »

credit_guy wrote: post #11

The application doesn't really make sense the way they explain it: use CO2 from a power plant to produce syngas. If the power plant burns methane, you might as well produce syngas straight out of methane, and short-circuit the step where you produce CO2. From the net energy usage point of view, you are better off (otherwise, you just found a recipe for perpetual motion). Where this could make sense is energy storage.…

You’re correct but It still makes sense as a way to get existing power plant operators on board the green energy train. It’s probably cheaper to retrofit an existing plant to harvest the generated co2.

Re: Engineers find neat way to turn waste carbon dioxide into useful material

#32

Post by travisporter »

lykr0n wrote: post #3
crimsonalucard1 wrote: post #2

Doesn't the net CO2 in the air increase? So you harvest CO2 to into fuel. That fuel is burned and the CO2 is released back into the air. So net difference is zero. But to harvest the CO2 you needed to generate a high amount of heat. That's extra CO2. So net CO2 is more. It depends on the cost of harvesting that CO2.

You can use Solar and other renewable energy to power the conversion process. Progress is still progress. I would much rather to pay more for net zero carbon fuel, then not do anything.

It’s actually strange that no gas company is advertising something like this. I’ve seen so many industries advertise even the tiniest carbon offsets but why can’t BP or Exxon sell a net zero or at least low emissions fuel

Re: Engineers find neat way to turn waste carbon dioxide into useful material

#34

Post by ashtonkem »

carapace wrote: post #25
bit_logic wrote: post #10

Every time there’s a discussion about synthetic carbon fuels, there’s the same frustrating replies. I want to reply to those with one statement: the whole point is to use excess power from solar/wind. There’s always the same replies pointing out how it’s more efficient to use the power directly in EV batteries, laws of thermodynamics, and other similar things. Those completely miss the point. Solar/wind is going expo…

Bucky Fuller had the idea to just connect the world's electricity grids together. He called it "World Grid" I think.

That’s more efficient, but difficult politically and logistically.

Re: Engineers find neat way to turn waste carbon dioxide into useful material

#35

Post by m4rtink »

virtue3 wrote: post #22
ZeroGravitas wrote: post #16

Earlier quoted context omitted.

You don't need carbon to store energy, you can just stop at hydrogen (or use nitrogen to make ammonia). Processes can be refitted to use pure hydrogen or it can just be added in small increments to existing gas burning plants. Replacing anything that burns fuel with carbon in it with alternatives that dont is a better solution.

hydrogen is notoriously difficult to store. Being an atom "thick" generally means it leaks through containers regardless of what you try to do. And I don't know if you've played the game "Oxygen Not Included", but creating liquid hydrogen is no easy task either. A more dense energy storage substance (such as a hydrocarbon) would probalby be more efficient in terms of transportation / use / storage.

Hydrogen leaks in an oxygen atmosphere (like the one here on earth) are pretty dangerous, as they are effectively invisible in daylight, due to almost all the energy going directly to infrared. Due to that NASA test engineers used to walk with a broom in front of them in areas where hydrogen leaks could happen. If the broom suddenly caught fire, there was a burning hydrogen leak in front of the engineer! A picture of this can be seen here:

https://spinoff.nasa.gov/spinoff1997/ps1.html

Not just leaks, hydrogen can destroy the structure of many metals and make them brittle: https://en.wikipedia.org/wiki/Hydrogen_embrittlement

And another issue is the very low density - you van see it with hydrolox rockets, how big they are & how their liquid hydrogen tanks are compared to the LOX tanks. This adds up in tank weight, removing some of the energy/density benefits. This is one of the reasons many next gen rockets are opting for liquid methane instead of liquid hydrogen.

Re: Engineers find neat way to turn waste carbon dioxide into useful material

#36

Post by nine_k »

carapace wrote: post #25
bit_logic wrote: post #10

Every time there’s a discussion about synthetic carbon fuels, there’s the same frustrating replies. I want to reply to those with one statement: the whole point is to use excess power from solar/wind. There’s always the same replies pointing out how it’s more efficient to use the power directly in EV batteries, laws of thermodynamics, and other similar things. Those completely miss the point. Solar/wind is going expo…

Bucky Fuller had the idea to just connect the world's electricity grids together. He called it "World Grid" I think.

Geography may also be a problem. Running a gigawatt cable from sun-soaked Australia anywhere in SEA is enormously expensive. Instead, packaging the energy into carbohydrates produced from waste water (cleaning it in the process) and waste CO₂ may be much more economical and convenient. You can likely produce the best quality Jet A fuel or octane 98 gasoline with little other fractions by tuning the synthesis process (unlike an oil well which gives you a mix you can't control).

Beside that, a transatlantic jet, let alone a Falcon 9, won't ever fly with battery power. You still need highly energetic fuels where power density is at a huge premium.

Re: Engineers find neat way to turn waste carbon dioxide into useful material

#37

Post by clouddrover »

bit_logic wrote: post #10

Every time there’s a discussion about synthetic carbon fuels, there’s the same frustrating replies. I want to reply to those with one statement: the whole point is to use excess power from solar/wind. There’s always the same replies pointing out how it’s more efficient to use the power directly in EV batteries, laws of thermodynamics, and other similar things. Those completely miss the point. Solar/wind is going expo…

Yes, it's worth making use of the excess power. The Orkney islands, for example, are using their excess wind and tidal power to produce hydrogen:

https://edition.cnn.com/videos/business/2020/03/06/orkney-hy...

Re: Engineers find neat way to turn waste carbon dioxide into useful material

#38

Post by effie »

travisporter wrote: post #32
lykr0n wrote: post #3

Earlier quoted context omitted.

You can use Solar and other renewable energy to power the conversion process. Progress is still progress. I would much rather to pay more for net zero carbon fuel, then not do anything.

It’s actually strange that no gas company is advertising something like this. I’ve seen so many industries advertise even the tiniest carbon offsets but why can’t BP or Exxon sell a net zero or at least low emissions fuel

It is really strange to you that oil company is not advertising a product that they don't have, a product which would compete with their regular product, a product which is hard to sell (more expensive and dubious value)? From the standpoint of these companies, there is plenty of oil down there, making synthetic one has no upside.

Re: Engineers find neat way to turn waste carbon dioxide into useful material

#39

Post by nine_k »

credit_guy wrote: post #11

The application doesn't really make sense the way they explain it: use CO2 from a power plant to produce syngas. If the power plant burns methane, you might as well produce syngas straight out of methane, and short-circuit the step where you produce CO2. From the net energy usage point of view, you are better off (otherwise, you just found a recipe for perpetual motion). Where this could make sense is energy storage.…

This makes complete sense if you replace a power plant that produces electricity with an industrial process that produces heat, e.g. a blast furnace.

Then you can grab the waste CO₂ and turn it into something useful (ultimately liquid fuel, plastics, etc) by using the cheap solar energy, of which we often have a surplus at daytime.

This has the downside of only operating efficiently during sunshine, or needing a power transmission line from somewhere under sunshine currently (e.g. during local night).

Re: Engineers find neat way to turn waste carbon dioxide into useful material

#40

Post by selectodude »

nine_k wrote: post #36
carapace wrote: post #25

Earlier quoted context omitted.

Bucky Fuller had the idea to just connect the world's electricity grids together. He called it "World Grid" I think.

Geography may also be a problem. Running a gigawatt cable from sun-soaked Australia anywhere in SEA is enormously expensive. Instead, packaging the energy into carbohydrates produced from waste water (cleaning it in the process) and waste CO₂ may be much more economical and convenient. You can likely produce the best quality Jet A fuel or octane 98 gasoline with little other fractions by tuning the synthesis process…

Not even power density but also the ability to get lighter as you go farther.
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