Low-cost, battery-like device absorbs CO2 emissions while it charges | Hacker News Reader

Low-cost, battery-like device absorbs CO2 emissions while it charges

techxplore.com

55 pointsPaulHoule41 comments

"the size of a two-pence coin" -- I need to know how many football fields that equates to. Heavens forbid using actually sensible units.

https://en.wikipedia.org/wiki/Two_pence_(British_decimal_coi...

About 2mm thick, 26mm diameter, masses about 7g.

So about 0.00237 football fields, then.

If it's a tiny tiny football field.

"American" or "Association" football ? (Ironically, FA-aka-soccer fields do not have a standard size, only standard boundaries, so they would not be a valid unit of length anyway...)

I used an American football field, and only the length, and my math could be off. When I read “X football fields long” I assume American football, and when I read “X football pitches long” I assume Association football. Or at least I would have, if I had ever encountered it.

“Football field” as a standard is, I believe, based on American football. Which is odd, because American football is non-migratory.

Non-migratory USA-only standards seem, well... Standard?

I don't think he wanted to know the specifics of a two-pence coin, but was rather lamenting the overuse of rough and localized units in lieu of logical and standardized ones.

Ok, someone indulged your complaint.

What did you /learn/ from this? Do you actually know more about the capacitor than when you were just told it was coin sized?

Imagine if there was basically 0 cost carbon capture device that ran completely off of solar power and didn't just store CO2 but also expelled oxygen and miraculously created useful usable materials...

Trees, right?

Maybe even coconut palms! /s

If you can shrink it down to the size of a two-pence coin, you have a winner.

Oh sure, and while we're dreaming, imagine that it's nanotech so it repairs itself automatically and can even make copies of itself.

Even if such a ridiculous "Star Trek" miracle device were possible to build with today's technology, it would just ruin the economy.

My educated environmentalist friends are complaining loudly about forest-planting programs the way they are implemented being pad for CO2 absorption (because they replace healthier ecologies) on top of being terrible for the local ecosystems. Ecology is _complex_.

Yeah, clear-cutting a forest and replacing it with e.g. a pine mono-culture is probably a net negative, eh?

I've heard of a method that revives native forests rapidly: https://daily.jstor.org/the-miyawaki-method-a-better-way-to-...

Where will you put them? A recent study showed that just to offset _the yearly increase_ in CO2 emissions we would need to plant an entire continent of trees every year. And then ensure that they get adequate quantities of water.

Human CO2 emissions are so far off the scale of anything that has ever happened naturally that nature as she evolved on Earth has no way coping.

The best developed idea for CO2 disposal today is to compress to 1500 psi and inject into a saline aquifer. It isn't that hard to do, people have been doing injection into oil formations since the 1980s for "Enhanced Oil Recovery".

There are some questions about how long it stays there, induced seismicity, etc. but the way you're going to find out about this is by doing.

First you would need an economical method to capture the co2.

I ran some numbers on running an algae bioreactor for carbon capture last year. Totally easy to do, but there's two problems for home use.

First, the typical American carbon footprint is like 15 tons. Which means that a successful backyard bioreactor will have many tons per year of captured carbon to move and dispose of.

Second, the amount of air that needs to be pulled through the system to even have access to 15 tons of carbon is /enormous/. Because CO2 concentrations in air are still very tiny. So a working system pulling a significant portion of one person's carbon footprint will require a really large fan and air management system.

The full paper pdf is here. https://pubs.rsc.org/en/content/articlepdf/2022/nr/d2nr00748...

The marketing fluff in the techxplore article is a bit too high compared with the actual paper that doesn't make any of these claims. For example, the fluff says "sustainable materials", "coconut shell" whereas the paper accurately says ypf-50 which is a bulk manufactured activated carbon material which could be made from coal just as much as it could be made from coconut shell.

It's a small device and who knows if it will scale up and at what price point. But it's still a neat find, even if the press folks writing the beginning of the article have filled it with fluff. There's some actual details below the fluff.

I haven't read the article yet, but, judging the title, IMHO seems just another marketing balloon: under the skin only hot air. The "device absorbs CO2 emissions while it charges" : I don't think that something like that can solve the problem of global warming or even reduce the side effects in a way we can measure, justifying the hype about that characteristic.

EDIT: I've read the article: "is the size of a two-pence coin", so how many fraction of ug of Co2 can absorb of the "Around 35 billion metric tons of CO2 are released into the atmosphere per year" ? But the last part is fantastic: "The results from Temprano's contribution help narrow down the precise mechanism at play inside the supercapacitor when CO2 is absorbed and released", so when the battery discharge release the Co2 again , right? So what is the point of the whole article?

The best developed method of removing CO2 from waste gas streams is:

https://www.sulzer.com/en/shared/applications/amine-treater-...

In that case you are heating and cooling a liquid in which the CO2 dissolves and then goes out of solution. In one phase you are removing CO2 from the waste gas stream, in the other one you are producing a stream of pure CO2.

That device works basically the same but with electricity rather than heat.

Ok, but, if I've understood correctly , at the end of article they suggest that the CO2 captured while the battery was in recharging state is released when the same battery is in use. In other words the battery doesn't capture permanently the CO2 as the gas stream method you just mentioned: the battery isn't like a black hole for CO2, it simply "breath" releasing the CO2 when it's discharging. So in what way that should be a solution for the global warming ? If they want capture the CO2 in discharging phase, they need to store a big number of coin size batteries in an industrial facility that needs batteries for some reason, plus you are using electricity that likely was produced burning fossil combustibles to remove CO2 from air. So no laptop or cellphone removing CO2 from our atmosphere.

The best answer right now for CO2 disposal is to compress it to 1500 psi and inject into a saline aquifer. The gas has to be really pure to do that and that kind of device could do that purification.

I wonder about practical implementation of this in large scale? So it absorbs and releases CO2, but how do you do releasing to essentially environment where it is reasonable to capture it back?

I think what they are suggesting is that you charge by feeding air, with its very low percentage of CO2. Then when you discharge you are releasing concentrated CO2 which you capture and do something responsible with.

So it is an electrical storage device which incidentally is a CO2 concentrator.

Responsible use of the CO2 might be as simple as dumping it and the waste heat into a greenhouse to grow vegetables.

Now can we build a cryptocurrency that's mined by extracting CO2 from the atmosphere?

Wouldn't the most efficient way to mine such a coin be to be in an area with above average CO2 levels? Such as a closed room where you are burning oil/gas/wood? Have you heard of the cobra effect? See https://en.m.wikipedia.org/wiki/Perverse_incentive . Not saying what you suggest is impossible, but if it's possible to game the system I suspect it will be a net negative very quickly.

Recently there was that blue-algae powered computer. Wonder if that concept can be used. But at ocean scale.

Carbonminers would probably rather produce CO2 so they can "extract" it at much higher rate, instead of using the one in the atmosphere.

Edit: Ups this was already said.

Make a government buying carbon. Like one cubic meter is $1000 or whatever cost would be interesting. Spend the money and bury those cubes in deep shafts. Let the market handle it.

I think something like that would have to be manually audited by humans (i.e. you'd need to agree on a central authority who certifies volumes of carbon sequestered).

I was thinking the other day that maybe something that could be easier to objectively verify is something like a cryptocurrency where you generate a unit of currency when someone votes. Sort of like "I voted" stickers as a form of money. It's not a fully formed idea; I don't know how the logistics would work.

Bonus points if the currency as a whole is valued higher or lower based on individual voters rating their voting experience. Like, you ask them on a scale of 1 to 10 if they think they have a real voice in how their government is run. Thus countries would have an incentive to be democratic in a way that's truly responsive to the people and not just some kind of democracy theater.

  > I think something like that would have to be manually audited by humans

Such a body would refuse to audit e.g. Wikileaks or Syria or North Korea do to some political BS which has nothing to do with the issue at hand.

“designed in part from sustainable materials”: wow what a way to phrase that :)

“Each copy contains a certain percentage of recycled paper.”

"And what percent is that?"

"Zero... zero’s a percent."

Sort of like when a food product is advertised as "Made with real cheese". I assume this means that the product is all chemicals, but there's a block of cheese in the factory manager's lower desk drawer.

One of my influential childhood memories was realizing that a product labeled 95% Fat Free was probably 5% fat.

“And other artificial flavors”

Any food product that uses terms like "home style" or "home-made flavor" should be required to include large, lurid pictures of the factory floor where the stuff is made.

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