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Scientists Discover Efficient Process to Turn CO2 into Ethanol

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Re: Scientists Discover Efficient Process to Turn CO2 into Ethanol

#61

Post by bryondowd »

gravypod wrote: post #59
benwikler wrote: post #32

Earlier quoted context omitted.

So basically: this is nice, but there's no reason yet to think that this could be the way we slurp carbon out of the atmosphere and avert climate catastrophe. Right? Drat.

Well we already have a solution for that. We just need to create massive farms on unused land. Plant enough stuff to feed the world populations of humans with large excess and you're going to also plant enough things to scrub co2 out of the atmosphere.

Just curious, but my understanding is that plants are generally carbon neutral. Any CO2 that is taken in by a plant is eventually broken back down and released after the plant dies and is consumed or allowed to decay. Unless you take a significant amount of that plant matter and contain it so that the carbon can't be re-released, at best you get a static reduction of CO2 directly proportional to the increase in live plant volume.

So, no carbon scrubbing while feeding the world, but you could maybe scrub carbon by taking massive amounts of excess crops and burying/sealing them away. Not sure what the cost/efficiency of that would be.

Re: Scientists Discover Efficient Process to Turn CO2 into Ethanol

#62

Post by undersuit »

btbuildem wrote: post #36
AlexCoventry wrote: post #31

Earlier quoted context omitted.

The main question is whether there's a carbon sequestration process which can be industrialized so that it's more effective than planting trees.

Not sure we want to start competing with trees -- what if we get better than them at it? Do trees start dying for lack of CO2?

If we could process enough CO2 to reverse current inputs(i.e. the equivalent of hundreds of billions of tree growth) we could possibly think about scaling up the process to remove all the CO2 from our atmosphere as fast as we can. But we won't run out of CO2 unless we take all the ethanol we're producing with the CO2 and store it, instead of generating energy from it via combustion.

Re: Scientists Discover Efficient Process to Turn CO2 into Ethanol

#63

Post by adwn »

bryondowd wrote: post #61
gravypod wrote: post #59

Earlier quoted context omitted.

Well we already have a solution for that. We just need to create massive farms on unused land. Plant enough stuff to feed the world populations of humans with large excess and you're going to also plant enough things to scrub co2 out of the atmosphere.

Just curious, but my understanding is that plants are generally carbon neutral. Any CO2 that is taken in by a plant is eventually broken back down and released after the plant dies and is consumed or allowed to decay. Unless you take a significant amount of that plant matter and contain it so that the carbon can't be re-released, at best you get a static reduction of CO2 directly proportional to the increase in live…

You are correct: To get a net reduction of atmospheric carbon dioxide, you need to increase total plant mass or prevent plants from decomposing/being eaten.

As far as I know, the majority of net oxygen production happens through algae, because they die and sink to the bottom of the ocean, permanently removing carbon from the carbon cycle.

Re: Scientists Discover Efficient Process to Turn CO2 into Ethanol

#64

Post by Gatsky »

weatherlight wrote: post #39
Gatsky wrote: post #29

I don't get the point of this. We already have a self propagating machine that can turn carbon dioxide into a useful carbon substrate that is stable over long time periods, and is a thoroughly proven carbon sequestration technology. It's called a tree.

I do agree wholeheartedly, but the problem with trees is that they die and then they rot releasing all that carbon back into the atmosphere. It's a good start though! It be awesome if we had some sort of technology that sequestered carbon (where it be in the form of CO2 or wood chips, and sorted that carbon in a solid form effectively indefinitely. for trees to be a permanent solution, we would have to convert 50% of…

This is a problem with 'organic' sequestration. However, trees are relatively long lived and take a long time to fully decay. Suitably harvested and treated wood also lasts a long time. Young growing trees sequester the most carbon, so you could have a cycle of logging older trees and replanting shrubs to maximise the sequestration. Some types of bamboo grow incredibly fast, as much as 90cm a day.

I did some back of the envelope calculations. It would take something like 240 billion extra trees to return us to pre-industrial carbon dioxide levels. This sounds like a lot, but it certainly isn't physically impossible. The Amazon has 400 billion trees. Finding suitable land mass for this purpose is an issue. But trees are remarkable, they grow in many inhospitable places. Mangroves for example survive in very difficult conditions with salt water and changing tides. So there is not necessarily an overlap with arable land. There are always more ambitious things you can try, like GMO trees that can grow in the desert, or giant floating forests in the Pacific

Also, if we could stop deforesting the Amazon currently, that would be a good start

Re: Scientists Discover Efficient Process to Turn CO2 into Ethanol

#65

Post by m_mueller »

ci5er wrote: post #56
m_mueller wrote: post #55

Earlier quoted context omitted.

Energy density is great, but for most current usecases I'd argue it's not really necessary. It's neither needed in your home (lots of space to put batteries, is connected to a power line), nor for your daily commute, nor for agriculture, nor for heavy industry (even better power lines), nor for long distance land based transport (trains are just as good and can be electrified easily) which covers the largest energy c…

80/20 rule and all that, I agree. I'm originally from a ranch in Wyoming 65m+ from the nearest grocery store, and those use-cases (ag, distance) are burned into my gut. It makes for some bad intuitive generalized conclusions on this topic from time-to-time.

no sweat, it's a pleasure to communicate with people who are able to think systematically and who can do an actual discussion rather than just shouting from rooftops.

Re: Scientists Discover Efficient Process to Turn CO2 into Ethanol

#66

Post by larvyde »

ju-st wrote: post #46
weatherlight wrote: post #39

Earlier quoted context omitted.

I do agree wholeheartedly, but the problem with trees is that they die and then they rot releasing all that carbon back into the atmosphere. It's a good start though! It be awesome if we had some sort of technology that sequestered carbon (where it be in the form of CO2 or wood chips, and sorted that carbon in a solid form effectively indefinitely. for trees to be a permanent solution, we would have to convert 50% of…

The co2 released by a dead tree is captured again by the next tree. So don't look at single trees but at whole forests.

Which means less atmospheric carbon that we actually want to scrub gets captured by that 'next tree'...

Re: Scientists Discover Efficient Process to Turn CO2 into Ethanol

#67

Post by AstralStorm »

adrianN wrote: post #35
Gatsky wrote: post #29

I don't get the point of this. We already have a self propagating machine that can turn carbon dioxide into a useful carbon substrate that is stable over long time periods, and is a thoroughly proven carbon sequestration technology. It's called a tree.

Plants capture about 1% of the incoming sunlight energy into chemical energy. We might be able to come up with a process that is more efficient.

But would the process scale? If it requires substantial amounts of rare earth minerals or very energy intensive manufacturing it will still be unworkable.

Re: Scientists Discover Efficient Process to Turn CO2 into Ethanol

#68

Post by AstralStorm »

acveilleux wrote: post #26
maga wrote: post #12

>The catalyst’s novelty lies in its nanoscale structure, consisting of copper nanoparticles embedded in carbon spikes. This nano-texturing approach avoids the use of expensive or rare metals such as platinum that limit the economic viability of many catalysts. How about large scale production of the catalyst? Do we have any idea of how to produce efficiently a "nanoscale structure consisting of copper nanoparticles e…

No idea about this material in specific but a lot of nanoscale stuff is manufactured using photo lithography, basically the same way we make micro conductors since it's a process we understand well and we can scale (just ask Intel.) It sounds like this material would have good tolerance for minor imperfections (unlike IC) so yield could be really good.

The problem with this one attempt is the energy input required for it to work. That requires major research on the cathode.

Re: Scientists Discover Efficient Process to Turn CO2 into Ethanol

#69

Post by btbuildem »

adrianN wrote: post #51
btbuildem wrote: post #36

Earlier quoted context omitted.

Not sure we want to start competing with trees -- what if we get better than them at it? Do trees start dying for lack of CO2?

It's not like we couldn't stop if the CO2 levels dropped too far.

Just like we are able to stop now, as the CO2 levels are life-threateningly high, right?

Re: Scientists Discover Efficient Process to Turn CO2 into Ethanol

#70

Post by ci5er »

m_mueller wrote: post #65
ci5er wrote: post #56

Earlier quoted context omitted.

80/20 rule and all that, I agree. I'm originally from a ranch in Wyoming 65m+ from the nearest grocery store, and those use-cases (ag, distance) are burned into my gut. It makes for some bad intuitive generalized conclusions on this topic from time-to-time.

no sweat, it's a pleasure to communicate with people who are able to think systematically and who can do an actual discussion rather than just shouting from rooftops.

Please, don't mistake me - I'm still opinionated. I just got tired of yelling on the Internet. :-)

On this topic, though, in this context: no need to yell. You make a good point.

I will say that it is devilishly hard. Liquid fuels have some impressive characteristics, that make them an easy "go-to" for almost 100% of our heavy portable-power use-cases, and economic alternatives for those use-cases must almost be developed one-at-a-time. I'm an engineer, not a policy constructivist, so somebody saying "tax it" to bring alternatives to economic parity is vaguely unsatisfying to me.

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