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That's very interesting, but is it cost effective to get carbon out of the atmosphere rather than to drill it out of the ground?

Put another way, you can either build 10 wind turbines with atmospheric carbon fiber, or 11 turbines with carbon fiber made from petrochemical feedstocks. Which option ultimately has a bigger reduction in CO2 emissions over the lifetime of the turbines?

It seems obvious that if synthesizing butane from atmospheric CO2 was anywhere near economic after applying a carbon tax, global warming would not be an existential threat. I'd love to be wrong, obviously...

Depends on where you are! On Mars, for example, it's going to be far more cost effective to get carbon from the Martian atmosphere and water from the subsurface than to ship carbon feedstocks from Earth.

Currently, these technologies are approaching parity on cost fairly quickly. It's basically at the prototype stage presently, so much more expensive, but widespread adoption and economies of scale could change that within several decades. The upfront costs are quite high, similar to any petrochemical complex, i.e. in the multi-billion-dollar range for any facility capable of significant industrial-scale output.

> Currently, these technologies are approaching parity on cost fairly quickly. It's basically at the prototype stage presently, so much more expensive, but widespread adoption and economies of scale could change that within several decades.

Sorry, but how could that possibly work from even a first principles perspective? Oil is literally just pumped out of the ground, whereas you have to overcome the entropy of highly disperse atmospheric CO2, and then you have to add the enthalpy of the hydrocarbons!

But then, you have to distill it and strip out the sulfur and other elemental contaminants and fractionate it and crack it... one benefit of starting off with pure CO2 and water is the ability to selectively make pure hydrocarbon fractions (or at least fairly restricted spreads of chain lengths) without having any waste.

Also, there's the distribution issue - this could all be done regionally, so transport costs will go way down. The only thing needed is excess energy to dump into the process (equatorial zones would be good for solar PV inputs, etc.)

Climate change isn't an existential threat if all governments and international corporations follow a carbon (more precisely GHG) pricing scheme.

The crisis is that its politically hard to coordinate that agreement and transition and we've not made as much use of the last four decades as we could have. Potentially passing irreversible tipping points.

Would be cool to see!

I know spacex had trouble finding autoclaves big enough for carbon fiber tanks. I would expect windmill blades need to be even bigger and hence need a bigger autoclave. So that would be a major challenge.

Then again this is a huge market, and the mentioned gains are quite big. So the economic benefits might be big enough that someone dares build an autoclave for carbon fiber windmill blades.

I kind of doubt it. carbon fiber has pretty bad impact resistance which is necessary because the blades are spinning quickly enough that dust over time erodes the leading edge

Don't all wind turbine blades use various coatings / tapings on the leading edge to prevent degradation over time?

https://www.lmwindpower.com/en/services/the-problade-ultra

> "Leading edge erosion (LEE) is a phenomenon where the leading edge of a wind turbine blade is eroded due to rain, hail, UV, sand, dust, and numerous airborne particulates. Since wind turbine blades are built to last over 2 decades, this erosion exposes the fiberglass beneath and ultimately impacts the blade’s life causing the turbine to produce less energy over time."

It takes periodic maintenance to repair the blade and restore efficiency.

I’m wonder how the eroded fibers are from an inhalation risk perspective.

Approaching zero compared to the emissions of fossil fuel power plants, I assure you

Fossil plants emit radionuclides (coal) and, obviously, lots of other things. But dismissing fiber inhalation risk from their replacement because fossil plants are bad is pure sophistry.

Hmm, we make aircraft, including supersonic ones, out of carbon fiber. So surely the problem is manageable somehow? If nothing else, put some metal plates on the leading edges?

most of the time an airplane is at altitude where there is a lot less stuff in the air. (and when they're at low attitudes, they are going a lot slower)

> Also, if you just bury the worn-out carbon-fiber blades in stable landfills

I think it's probably better to just burn the carbon fiber. As you point out, it's not a significant amount of carbon, and it's a tidier solution with less risk of unintended consequences. If you want to capture and store carbon, burn it in a trash burning power plant that captures CO2. Then you have a more general-purpose solution for CO2 capture that you can feed any other carbon-based waste. (Of course, Reuse, Reuse and Recycle first, but eventually everything degrades to the point where it's best to burn it. This also helps pull out environmental toxins and heavy metals from materials we've made)

There's an interesting project in Norway to test trash burning with pure oxygen. The gas in the chamber will in effect be a mix of O2 and CO2. The released CO2 is recycled and the O2/CO2 mixture is controlled to optimize the temperature. This makes the trash burning, the cleaning of the exhaust and the CO2-capture more efficient.

Carbon fiber is indeed superior in many ways, but it’s also very expensive. At least that’s the impression I get from it being used only in expensive cars.

So it seems to only be worth it if it doesn’t increase the total cost of a new wind turbine by too much compared to the added efficiency.

It is more expensive, because the process to produce it is less mature than metal alloy based solutions.

For example BMW invested a lot of money into carbon fiber production development and can now use some of the knowledge and technology in more mainstream products starting with iX SUV.

Carbon fiber certainly has advantages vs. fiberglass. But this article was about the resin material, which forms, depending on the application, maybe around 50% of the weight. But maybe it's possible to produce epoxy resin by starting from atmospheric CO2 and Fischer-Tropsch synthesis as well, IDK.

Of course, glass fiber wins here, being just molten rock extruded through a nozzle (well, quite simplified, but you get the idea). No expensive hydrocarbon synthesis required.

> Carbon fiber could plausibly be made without reliance on any fossil fuel inputs. The chemical synthesis pipeline is (working backwards):

Nice one! Is there any literature on this without beeing a PhD in Chemistry (but in another Natural Science)?

The important magic is that carbon and hydrogen given enough pressure will form hydrocarbons (basically as dead plankton deep below the tectonic plate did), so doing it the brute force way is simple, but very energy intensive.

Split CO2 to CO and O, split H2O to H2 and O.

CO + H is syngas, used as feedstock for synthetic fuels.

Then using a metal catalyst (iron or cobalt for example) and heat and pressure good old "organic chemistry" does the rest, various hydrocarbons form (and water as residual by product). This reaction itself gives off heat, so at least this part doesn't need that much energy.

https://en.wikipedia.org/wiki/Synthetic_fuel

https://en.wikipedia.org/wiki/Fischer%E2%80%93Tropsch_proces...