A while ago carbon capture startups were somewhat known on HN. I remember because i argued under seemingly each of them that their concept is not sound in terms of thermodynamics.
So when i saw this VOX article, i felt the need to post this here a la "told you so".
My understanding is that carbon capture at the time of emissions is extraordinarily difficult/impossible. However accelerating the carbon capture process through enhanced rock weathering and similar technologies is quite practical. The challenge is that one would need to purchase such carbon offsets in a way that isn't prone to rampant fraud.
Well it is obviously going to take energy to reverse the process. I do not think any of them have argued differently.
I am bullish on some kind of fuel-from-air technology gaining widespread adoption. Something to act as a sink to the increasingly glut of “free” renewable energy (assuming they can beat out the crypto miners). As far as I know, it is strictly a matter of price, there is no technological reason why it cannot work.
I have a great idea for a startup which bioengineers a solar-powered carbon capture system. These systems would capture carbon and embed it in cellulose. That cellulose could then be used for a variety of purposes: as a building material, fuel source, etc.
We could engineer these systems to be very aesthetically pleasing, with colorful 'leaves' and various types of cellulose layers of different colors and hardness. They'd be useful as shade structures, and they could also have other uses such as preventing soil erosion.
But what would happen to those cellulose machines long term? What might large quantities of the residue look like if left buried for, say, a couple million years?
Might well prove to be a valuable resource for large scale energy production in a distant future!
I think overall it'd be cheaper to make fuels for ICE from air than to trash and rebuild every single vehicle. We probably need fusion energy to make that a reality though.
> As far as I know, it is strictly a matter of price, there is no technological reason why it cannot work
Trees, bogs, and permafrost are already super efficient at carbon capture. This is more of a culture/incentives problem than a technology problem.
Plant forests, cut them down, turn them into housing or whatever. Voila: carbon captured for the next 50 or so years. People would love to pay you for cheaper abundant lumber.
> Peatlands are the largest natural terrestrial carbon store. They store more carbon than all other vegetation types in the world combined. Damaged peatlands are a major source of greenhouse gas emissions, responsible for almost 5% of global anthropogenic CO2 emissions.
A quarter inch of lime will sequester as much carbon per acre as your peatland.
The numbers don't work for using plants for sequestration. 1-3% of the world's land is urbanized, the rest is either already green or doesn't support extensive plant life. We can increase the green land area number, but not substantially.
We can release thousands of years worth of carbon sequestration in a peat bog in a few days by destroying the bogs. We don't have thousands of years to put it back.
The economics don't work for industrial sequestration. The numbers don't work for green sequestration. Our only choice is to stop putting the carbon into the atmosphere in the first place.
I do not understand the argument. Historically you were describing harvesting some resource (oil from the ground, sun from the sky, wind from the air, etc) and calculating your return. Carbon capture is about taking energy today and converting it into a different form of stored energy. Energy conversion is not lossless -you end up with less embodied energy than you started. Who cares? If you are taking overproduced solar and turning it into methane/ammonia, you can now “store sunlight” for night or seasonal grid backup in winter.
It comes down to economics. Electricity is less valuable than a combustible fuel in several contexts.
>If you are taking overproduced solar and turning it into methane/ammonia
And that overproduced solar is made using... petroleum.
The argument is very simple: we're basically just burning up oil with extra steps, then pretending the intermediate products can somehow undo the damage caused by burning up that oil (and now claiming that we're getting fuel back!) aka "extend and pretend"
We need to stop putting that carbon into the atmosphere, because the reality is that the process isn't reversible on human timescales. The only answer seems to be degrowth, but asking for negative GDP is basically heresy.
Not my math. Industry's math. And it's bonkers because "green products" have to sell, electric cars have to sell, etc. The economy has to keep growing. Big Line has to keep going up.
What doesn't sell, but might actually help us get out of this mess? Mass transit, dense subsidized housing, remote work, degrowth (negative GDP). None of this stuff sells, especially the last one.
True but it’s also OK if EROEI is less than one when using renewables (think solar in africa)
In fact ROI is more important to focus on, given solar panels last 20 years and the cost of installation is covered in 10 years, it will create profit for 10 (oversimplifying). Then the methane can be converted to LNG and transported by ship to Europe/US or somewhere else
If you haven’t noticed we got into this mess by chasing profit, the best chance to get out of it is to make carbon capture economically viable that’s why making money is important part of the puzzle.
Alternatively some sort of world government or dictatorship would work too, but in democratic/capitalist society the problem wont get solved unless someone can make the moneys
Yes, people still regularly repeat the idea that carbon capture is worthwhile. Major tech companies invested in carbon capture projects (such as Google earlier this year with $35m investment into CCS).
Irrespective of the popular sentiment towards oil companies, CCS is a major component of climate policy towards net zero by 2050, and the article points out why the current trajectory needs significant and time-sensitive improvements.
