[eDISCO]

Interesting proposition. 1. Why would your process be more cost effective and/or efficient than the commercially available processes for alcohol production? Surely if the magic sauce is the nanotube alcohol/water separation then conventional alcohol sources from fermentation will start using it at some point and will be able to produce same fuel but cheaper and/or more efficient. Maybe you can show that [photosynthesis -> organic matter -> fermentation] is less efficient than your process using renewables as input?

2. Why use CO2 from Air? At 400ppm, there is 500 times less CO2 in air than in any powerplant exhaust, so using the same state of the art separation, for the same throughput, your equipment should be ~500 larger? That seems like a capex waste.

[rmcginnis]

The cost of the agricultural feedstocks to biofuels are not easy to reduce further, whereas renewable electricity is getting less expensive and likely has much further to go. I think CO2 to fuel will have a decisive cost advantage over biofuels.

The reason to use direct air capture rather that going for higher concentration point sources is one of scale. We want to produce fuel at scales much larger than can be accommodated by any other means that capture from the air.

[bluGill]

Why not go for the higher concentrations now? Why not target agricultural ethanol plants now? I grant that long term they are limited, but why not use them now?

Higher CO2 concentration seems like it ought to make your initial testing easier.

Likewise, if you are really more cost effective than distillation all the existing ethanol plants would love to replace their boilers with your system. It seems like a simple way to get a small cash infusion selling to them. They can convert their ethanol to gasoline as well, and have infrastructure in place.

What I'm saying is don't bite off more than you can chew. If any piece works now push it while getting the others working.

[akavel]

Maybe they need to quickly scale up because of VC backing and thus a requirement for a high return on the investment?

[aeorgnoieang]

I'd imagine retrofitting power plants to process their exhaust is itself an extremely expensive process.

Maybe they could setup their devices around plants anyways tho.