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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

#41

Post by perl4ever »

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.

I do not understand the concept that a property of a sum of a bunch of numbers somehow applies to those components.

Whether something is net zero depends on what you are adding it to; it's not inherent in that thing.

It's like, if you have a pile of blue things, then the pile is also blue. But other characteristics do not work that way. If you have a pile of things that each weigh 1 lb, then the pile does not weigh 1 lb.

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

#42

Post by LegitShady »

bit_logic wrote: post #26
skybrian wrote: post #21

Earlier quoted context omitted.

A problem with processes based on using excess power is that they use equipment inefficiently. If cheap power is only available for a quarter of the time then it would take 4x as long to pay for the investment in the equipment. Whatever scheme you set up to use excess power needs to be pretty cheap to make it worth running only a small part of the time, or it needs to be doing something especially valuable. Compare t…

Solar produces only during the day, but wind is at any hour. And these days, the idea of massive over-provisioning is being discussed to overcome the intermittent problem since solar/wind keeps getting cheaper and cheaper. The idea is simple, how to overcome the cloudy winter day issue? Simply overbuild a lot of solar/wind so it can still provide enough on a winter day. Then during summer, shutoff the excess power ge…

>Use the excess summer power to fill up a near empty dam with desalinated water?

Pumped storage hydroelectricity is the biggest form of power storage at the moment, and has efficiencies around 70-80%. The losses for desalinization (pumping through media) are ruinous compared to just pumping uphill, and storing desalinized water means you can't use it without spending potential power. There might be good reasons not to mix desalinization and energy storage.

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

#43

Post by woodandsteel »

Synfuels are very important for saving the climate. Yes, we need to eventually move all transportation to batteries, and we now have the technology to do that with cars and increasingly with trucking.

But for ocean ships and long-range airplanes we are nowhere near ready for that. And hydrogen fuel cells are not nearly good enough. So at least for many years the only way to make some important forms of transportation carbon-neutral will be synfuels

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

#44

Post by outworlder »

atrus wrote: post #33
gpm wrote: post #24

Slightly offtopic, what's the easiest way to scrub CO2 from air (e.g. in a house) without using up consumable materials? Some form of pressure swing absorption?

Probably a bunch of plants.

Under a lot of light, otherwise they would consume O2 as well.

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

#45

Post by m_mueller »

bit_logic wrote: post #27
wtracy wrote: post #20

Earlier quoted context omitted.

> the whole point is to use excess power from solar/wind. Thank you. > But converting that into carbon fuels that work directly in existing infrastructure and is effectively carbon neutral is a good option too. This approach seems really underrated, at least for transportation. Hydrocarbons still have the best energy density of the realistic options. We have a century of experience building ICEs with favorable power/…

Too often have environmentalists let the perfect be the enemy of good. I understand why they feel that way, for so long have they fought against fossil fuel companies and other interests. They feel like if they give an inch, they will take a mile and climate change is too urgent. And so they oppose any transitional technology. They want to push for only perfect solutions like EVs and batteries. But I want those envir…

Well, is it such a big victory for renewable? I think the big winner atm. is natural gas from fracking, which could easily be the final nail in the coffin.

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

#46

Post by marcosdumay »

gpm wrote: post #24

Slightly offtopic, what's the easiest way to scrub CO2 from air (e.g. in a house) without using up consumable materials? Some form of pressure swing absorption?

If you are concerned about indoor CO2 concentration, the answer is to ventilate the place.

No reasonable amount of plants will keep a house stable.

If it's just really curiosity, well, people have been scrubbing CO2 since space travel is a thing. Wikipedia was completely unhelpful to me, but I remember there is a mineral with high CO2 selectivity that you can simply push the air though it.

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

#47

Post by pabs3 »

bit_logic wrote: post #26
skybrian wrote: post #21

Earlier quoted context omitted.

A problem with processes based on using excess power is that they use equipment inefficiently. If cheap power is only available for a quarter of the time then it would take 4x as long to pay for the investment in the equipment. Whatever scheme you set up to use excess power needs to be pretty cheap to make it worth running only a small part of the time, or it needs to be doing something especially valuable. Compare t…

Solar produces only during the day, but wind is at any hour. And these days, the idea of massive over-provisioning is being discussed to overcome the intermittent problem since solar/wind keeps getting cheaper and cheaper. The idea is simple, how to overcome the cloudy winter day issue? Simply overbuild a lot of solar/wind so it can still provide enough on a winter day. Then during summer, shutoff the excess power ge…

One issue with carbon fuel is air pollution, we have seen during the pandemic that getting people out of cars is a big part of solving that.

Re water, in addition to filling dams with desalinated drinking water we could also refill aquifers that are being emptied by overconsumption of water (often leading to intrusion of saline water into the water table and associated problems).

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

#48

Post by gpm »

marcosdumay wrote: post #46
gpm wrote: post #24

Slightly offtopic, what's the easiest way to scrub CO2 from air (e.g. in a house) without using up consumable materials? Some form of pressure swing absorption?

If you are concerned about indoor CO2 concentration, the answer is to ventilate the place. No reasonable amount of plants will keep a house stable. If it's just really curiosity, well, people have been scrubbing CO2 since space travel is a thing. Wikipedia was completely unhelpful to me, but I remember there is a mineral with high CO2 selectivity that you can simply push the air though it.

98% curiosity, 2% lack of faith in our long term ability to keep CO2 levels down to healthy levels (1000ppm is enough that we can detect minor negative effects... I have to wonder if really minor ones exist even at 400 ppm).

Wikipedia was similarly not useful for me. Scuba divers and the like apparently use a one-time-use non-regenerative mineral that absorbs CO2. The space station has something that regenerates but I haven't been able to figure out what.

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

#49

Post by gpm »

atrus wrote: post #33
gpm wrote: post #24

Slightly offtopic, what's the easiest way to scrub CO2 from air (e.g. in a house) without using up consumable materials? Some form of pressure swing absorption?

Probably a bunch of plants.

Just in terms of numbers, you breathe out a kg of CO2 per day, you need to be growing more than a kg of plants per day to keep up with that.

That's a lot of plants.

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

#50

Post by PopeDotNinja »

LegitShady wrote: post #42
bit_logic wrote: post #26

Earlier quoted context omitted.

Solar produces only during the day, but wind is at any hour. And these days, the idea of massive over-provisioning is being discussed to overcome the intermittent problem since solar/wind keeps getting cheaper and cheaper. The idea is simple, how to overcome the cloudy winter day issue? Simply overbuild a lot of solar/wind so it can still provide enough on a winter day. Then during summer, shutoff the excess power ge…

>Use the excess summer power to fill up a near empty dam with desalinated water? Pumped storage hydroelectricity is the biggest form of power storage at the moment, and has efficiencies around 70-80%. The losses for desalinization (pumping through media) are ruinous compared to just pumping uphill, and storing desalinized water means you can't use it without spending potential power. There might be good reasons not t…

As I understand it, the main challenge with pumped storage is that you can't do it everywhere. You need fairly specific geography for it, and it's a big civil engineering project. Here's a good video on by Practical Engineering:

https://youtu.be/66YRCjkxIcg

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