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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

#21

Post by skybrian »

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…

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 to the strategy of locating somewhere that electricity is always cheap and running all the time.

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

#22

Post by virtue3 »

ZeroGravitas wrote: post #16
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…

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.

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

#23

Post by thereisnospork »

ajuc wrote: post #12

How are they converting CO2 into H2+CO? Where is the hydrogen coming from?

Water. In a conventional CO2 electrolyzer (electricity + CO2 -> CO + O2) where CO2 is dissolved in water (plus salt) H2 is the standard byproduct per H2O + electricity -> H2 + O2. The concept of CO2+H2O directly into H2 + CO is neither novel nor useful, as dedicated green-H2 production is more efficient.

This is an example of 'meh' level work being puffed up.

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

#25

Post by carapace »

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.

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

#26

Post by bit_logic »

skybrian wrote: post #21
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…

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 generation.

But what a waste of potential to do that! All that overbuilt power generation, simply turned off during summer. Batteries don't help here, it would store it, but then the question of what to do with it is still here.

If society goes the route of massive overbuilding solar/wind, then there's an opportunity to do something with effectively free power during summer. But it's ONLY during summer, so it needs to be something valuable that can also act as a energy storage.

Carbon fuel is perfect for this. Millions of ICE cars exist and are still being produced. Long distance airplanes will be carbon fuel based for a long time. And so many other uses. I think another option is water. Water can also be seen as a valuable resource that acts as energy storage. Use the excess summer power to fill up a near empty dam with desalinated water? Sounds like a perfect fit for regions like southern California or Arizona.

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

#27

Post by bit_logic »

wtracy wrote: post #20
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…

> 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 environmentalists to sit down and think. Yes, climate change is urgent, and that urgency should make you stop asking for perfection. There are 1.4 billion cars in the world. Even a 100% ban today on ICE car production is not going to change that. Cars have an average usable span measured in decades. The projections for 2050 are catastrophic if carbon emissions don't go down.

Green tech has one big overwhelming victory right now, solar/wind. It's annihilating coal and will eventually defeat natural gas as well. We can take that victory and use it to make the existing cars and airplanes carbon neutral. If you care about climate change, why is this not more exciting than EVs?

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

#28

Post by skybrian »

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…

Oh, but look at the equipment that's shut down, doing nothing, all winter! What a waste. Sure, the electricity is a bit more expensive, but it's still fairly cheap so why not turn it on and get some use out of it?

All processes have some waste. In the end, you need estimates done with real numbers to see if it's worth doing. We aren't going to settle it with casual chit-chat.

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

#29

Post by [deleted] »

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…

[deleted]

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

#30

Post by pm90 »

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.

I didn’t expect to see ONI in a hacker news thread!

Yes, hydrogen is an absolute mess to handle in free form, while hydrocarbons... stable, energy dense, and something we’ve had experience working with for a couple of centuries now.

A nice side effect would be that synthetic hydrocarbons might possibly reduce the dependency on oil for manufacturing plastics, dyes etc. It’s incredibly exciting... I don’t see how this isn’t a huge win.

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