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The article annoyingly failed to close the loop from the $1,000/ton figure at the top and do the math on the economic efficiency potential of this approach. How much electricity is required to sequester each ton of CO2 using this method, assuming you can amortize the construction costs over some long duration? I assume the intended installation is on the exhaust of a fossil fuel burning facility, but is it possible to install this next to a solar field and generate ethylene from excess mid-day production? Large scale carbon sequestration is one of the major unsolved problems of the 21st century and we have to expect many false starts before the really viable technologies emerge.

Time scale is also something I want to know about. "Can I remove CO2 from the air and turn it into something valuable in a way that is cost effective?" is one question. Another question is, "Can I remove CO2 from the air and turn it into something valuable faster than a tree?"

The writer appears to be under the impression that CO2 is not a valuable commodity.

In fact, it is, so long as it's under enough pressure, and in the right place. In Montezuma County, Colorado, sits the McElmo dome, an ancient underground CO2 well. They pump it out, down a 500 mile pipeline, to Denver City, Texas, where it gooses oil wells into pumping more crude out. Other than making more oil and making it cheaper, not really much in terms of greenhouse gas contributions- the CO2 starts underground and ends up underground.

Kinder Morgan won't just let you back up your truck and buy some (it's already spoken for), and even if they would, they'd expect you to pay a pretty penny for what we widely consider to be waste gas.

I think MIT is doing some good work. Just wanted everyone to be mindful of the massive scale under which CO2 is already getting bought and sold.

Permeating the PTFE layer with copper electrodes in order to get both hydrophobicity and conductivity seems stupidly simple, but the best ideas often are. I also greatly admire how their model looks like a s'more lol

Perhaps someone with more knowledge can comment on why solutions like these can't be used to solve the energy storage problem. Is it just economics?

That is, renewables are now the cheapest form of energy by a significant margin, but they are unreliable with respect to timing, so a storage solution is necessary in order to provide electricity on cloudy days when the wind isn't blowing, at night, etc. Most of the research I've seen into solving the storage issue involves batteries or things like pumped hydro. If things like solar and wind were "overbuilt", could a solution like this be used to create hydrocarbons when there is excess electricity? Power prices already go negative in some places when it's particularly sunny/windy. If the excess energy at that time could be used to make gas that could then be utilized by gas plants, well then there is your net 0 storage solution.

I'm assuming solutions like this are uneconomic (and similarly with hydrogen plants, e.g. by using the excess renewable energy to generate green hydrogen by electrolysis for storage and later use), but I'd like to understand better why.

Well, it uses PTFE which is a kind of PFAS which doesn't have a clear future and shouldn't be scaled up for good reasons, e.g. : https://www.gmp-compliance.org/gmp-news/restrictions-for-ptf...

(disclaimer that I do work in a related area)

The novelty of the underlying paper notwithstanding, a quick scholar search for "gas diffusion electrodes ptfe copper" will show that this is hardly an unexplored space.

My wife actually has established a cheap, energy-efficient facility for converting CO2 into useful materials right in our yard.

She planted a garden.

I was thinking about that the other day, how our beautiful trees, flowers, and bushes draw a few minerals from the soil, but are really mainly knitted together from the components of water and CO2.

Yes, yes, I know, planting more trees won't do much about the greenhouse gas problem at scale, but the only thing that will are the three P's: powerdown, permaculture, population control. I do not expect industry to solve the problem industry created in a way that doesn't create more problems.

To remove the co2 we put into the atmosphere will always take way more energy than we got out of putting it into the atmosphere in the first place. That is just thermodynamics.

To remove all the co2 we put into the atmosphere would take more energy than we extracted from fossil fuels since the industrial revolution. And all that energy would, of course, have to be produced in an absolutely carbon-free manner.

So this is and will remain an entirely impractical method of combatting global warming. MIT engineers know this. The people who funded this research know this. Why are they doing this?

It can never be as practical as leaving it in the fuel it came from. This is a waste of time, and only deepens the pit of climate catastrophe.

I'm very curious about how bioelectrochemistry might be used, eg [0]. I dream of artificial lichens on silicone wafers making sheets of graphene.

0: https://www.sciencedirect.com/science/article/pii/S258929911...

Trees also convert CO2 into something useful

Total waste of money and energy.

For the small amount of CCS we need, oceanic bio CCS is the way to go.

We're better off simply not emitting as much GHGs or digging up any more, and switching to renewables and distributed storage.

But isn't copper quite expensive? I didn't see them address this

Something that's not quite clear to me and is probably a stupid question if you know enough chemistry to be familiar with a gas diffusion electrode, but: can you run this thing on atmospheric air? Or will it only work if the gas in question is pure CO2?

Worst case scenario, you can always still turn it into wood.

What is needed is a Graphene Lightmill, turning driven by light alone, capturing CO^2 spinning out graphene as a monofiber, no in between steps, no conversions.

plant trees wait cut them down now you have wood to build stuff

repeat

It's always going to take more energy to convert CO2 to anything useful than it is to burn energy and release it as pollution. That means to requester all the extra CO2 in the atmosphere will require more energy than it took to put it there in the first place. Good luck humanity.

So….. turn it into more crap to pollute the earth.

In mice?

Okay, but why not work on making atmospheric methane more useful/practical? CO2 is less of a warming influence than methane, and there have been huge natural gas leaks (of methane) in the last 10-20 years. Even MIT admits that Methane is more important: https://climate.mit.edu/ask-mit/what-makes-methane-more-pote...