My two cents — change your name. Prometheus us too pretentious in my opinion. Also, Prometheus can be pronounced in different ways. Is it pronounced PromEEteus or PrometHeus? And its also ProMeth. :)
Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline
151–160 of 589 posts
Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline
#152Earlier quoted context omitted.
It would not make sense today, but in 10 to 15 years, with climate regulations, having a carbon neutral jet fuel might start making a lot of sense.
I expect I'll see new battery powered aircraft before I see today's aircraft powered by kerosene synthesized from water and carbon dioxide in the air. And we'll probably see more rail/car before then since the massive cost increase on airline tickets from this will destroy the industry.
I don't understand your rail/car replacing flying argument. There are no signs that flying is going to get so expensive that people would rather pay for it with so much of their time.
Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline
#153How is this different from what the US Navy has been trying to accomplish with turning seawater into Jet fuel? I know that they are extracting CO2 from the water instead of the air, but I believe the last I heard they had large inefficiency issues. And for them they plenty of power from their onboard reactor.
They couldn't get the economics right, but did succeed in making fuel. Their tech lead is an advisor of ours and is excited to get there this time!
Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline
#154Interesting 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 [photosynthes…
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 accom…
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.
Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline
#155Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline
#156Earlier quoted context omitted.
>If we replace fossil gasoline with renewable gasoline, that reduces CO2 emissions Nitpick: It will leave carbon emissions unchanged, but may reduce the amount added to the carbon cycle. What kind of production quantity are you looking at? Small batch aviation fuel for a niche "green" airline? Every semi truck on the road in America? The neighbor kid's go-kart? You give an "efficiency" of 60ish %, but I don't know ho…
We are going for the whole gasoline, jet fuel, and diesel market. The 100% efficient energy content of gasoline is approx. 34 kWh/ gallon. At 60% efficiency in converting renewable electricity to chemical energy, that would be approx. 57 kWh/gal.
Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline
#157Very promising but I'm going to hold out until I actually see this being applied in places like South Korea, literally suffocating from a combination of both local and foreign smog from Korea's favorite neighbor. You can't really fault me because we've often seen groundbreaking, extraordinary claims, and very little of it is actually realized. Sort of like how we get news about how somebody found a cure for AIDs or C…
I totally agree on skepticism. We are working hard to prove our economics. We are targeting selling renewable gasoline from the air for a profit next year. It will be much better for air quality too!
Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline
#158Earlier quoted context omitted.
With respect, that answer skirts the question of what happens to the water. You said you're using the nanotube membrane to separate petro products from the water. What do you do with the water left over? What state is the water in when the process is complete? Potable? In need of treatment by traditional water treatment facilities?
The water becomes the fuel. The hydrogen combines with the carbon in CO2 to form hydrocarbons, while the oxygen combines with itself to form molecular oxygen.
This implies there is still water there. Maybe it was poor phrasing, and all of the water is consumed, but that isn't what is stated.
Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline
#159Earlier quoted context omitted.
With respect, that answer skirts the question of what happens to the water. You said you're using the nanotube membrane to separate petro products from the water. What do you do with the water left over? What state is the water in when the process is complete? Potable? In need of treatment by traditional water treatment facilities?
If water is an input and not an output, that implies it's consumed, not left over.
This implies there is still water there. Maybe it was poor phrasing, and all of the water is consumed, but that isn't what is stated.
Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline
#160Here's what I don't understand - You're taking CO2 out of the atmosphere using renewable energy sources. Thermodynamically, this will take at least as much energy as it took to burn them. You did not mention how energy efficient your energy storage method is right now (50-60% at maturity sounds really optimistic, when plants are only a few %), but, in the short term, while we're still mostly using carbon-based fuels,…