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Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline

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Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline

#301

Post by bencoder »

Damorian wrote: post #30
lumberjack wrote: post #23

Earlier 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.

As the other reply pointed out, without a huge(like 5x) improvement in energy density (specific energy, actually) of batteries, this is physically impossible. Even with improvements, it would still be inefficient as batteries don't lose mass as they are used up - airliners can't even land with full fuel, they have to use it up, or dump it in an emergency situation.

Using a process like this would essentially make the fuel simply a much better battery for airplanes than our batteries today.

Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline

#302

Post by pulse7 »

One can get alcohol out of water at room temperature (28 degrees Celsius) by using pressure. Dr. Carl Jung used the distillation under pressure in 1908 to get alcohol out of wine and get alcohol-free wine. Wouldn't the same process work here?

Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline

#303

Post by maelito »

Correct me if I'm wrong, but planes look like a bad target for this fuel substitute : for 1 kg of CO2 emitted, estimates give a ~2 (or worse, 2.7 - 4) factor of radiative forcing (the potential for climate warming), due to the water vapor released at high altitudes.

You'd have to capture 2 or 3 times more fuel that you'd burn in the sky for this to be "net zero climate", which is a better metric than "net zero carbon".

Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline

#304

Post by aj7 »

dragonwriter wrote: post #229
aj7 wrote: post #227

To make combustible fuel from solar energy is crazy. The cost of such fuel is almost zero from the large oil reserves: the price you see is carefully calculated to maximize profits and to politically permit less efficient suppliers to survive and profit acceptably: but any synfuel business can be wiped out any time. At a point where we are trying for a renewable electric ecosystem, to take its product, and turn it in…

> To make combustible fuel from solar energy is crazy. The cost of such fuel is almost zero from the large oil reserves ...if you ignore the costs that exist in the form of environmental externalities, a behavior which is increasingly being recognized as an existential threat to human civilization.

I see, in other words, you have a method of capturing the externality costs, and using them to protect this fledgling enterprise. Look, I understand externalities. I understand 415ppm. I live in Hollywood, FL, and see flooding at high tides, with my own eyes. But the proposition here is to turn solar electricity into combustible fuel. And waste at least half of this energy in practice, because we have some "valuable" investment in fossil fuels infrastructure. Again, are you kidding me?

Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline

#305

Post by ineedasername »

rmcginnis wrote: post #217
ineedasername wrote: post #144

So if this is basically eliminating the traditional "distillation" phase by using the membrane, do you envision a day when I can dip your membrane in my beer and then poor off some moon shine?

Yes, you could do that now!

Well then, I'd like to place an order for all of them.

On a serious note though, that does present a novel use for these membranes within that industry. I imagine that optimizing the distillation phase for lower energy use and/or the possibility of distinct flavor characteristics that might coincide with alternate distillation techniques could be very compelling. Freeze-distillation has its own unique characteristics, I'd be surprised if this didn't also have some of its own.

Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline

#306

Post by TaylorAlexander »

NortySpock wrote: post #276
ballenf wrote: post #75

Earlier quoted context omitted.

Do those figures include gas taxes? Don't those make up a large part of the price at the pump?

In the US, gas taxes are low (I think I pay 15 cents per gallon tax on a total of $2.50 per gallon). Taxes are low as here in the US (a) many people hate taxes and (b) with such a low population density, commerce is very reliant on road vehicles. So raising taxes has an outsized impact on commerce.

California has higher gas taxes. Our gas is currently about $3.70 a gallon where I live.

Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline

#307

Post by 0000011111 »

As a person with a background in Environmental Studies, a c o2 to fuel conversion technology such as this sounds revolutionary! I am most curious about the fundementals.

Can you give us more specifics on the process such as;

1. What is the scale of the operation? Does this process need to be done at a large scale to work out economically? 2. Take a Boeing 737 for example which has a fuel capacity of ~6,875 Gallons. How much would it cost to build a C02 refinery that could produce that much fuel daily?

3. How much does it cost at a small scale? Say you have a miminal viable product that can refine 100 gallons of gasoline per day. What is the cost of that production in USD?

4.How many KWh of electricity would be required to refine 1 gallon of fuel using your current prototype?

I would love to hear / see data your numbers.

Thanks, 01

Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline

#308

Post by rmcginnis »

frankus wrote: post #80

Leaving aside the questions of cost-effectiveness/carbon neutrality/etc of e.g. corn ethanol, but can your tech potentially also make existing biofuels more efficient?

Yes, the CNT membranes will improve the efficiency of biofuels, but Prometheus won't do that. My previous company Mattershift makes the membranes and will sell them for other uses.

Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline

#309

Post by ineedasername »

rmcginnis wrote: post #173
geofft wrote: post #101

Earlier quoted context omitted.

I think you're asking a different question from the one being responded to (and the one being responded to is more obvious to me): I will try to help this conversation by restating the questions, both of you should correct me if I've misread this. Your question is, in the distillation step, the nanotube membrane separates fuel from water, leaving some amount of water; what happens to that water in the process? The qu…

Correct!

Thanks for confirming, though what if the ingested air/vapor/carbon mixture has a consistently higher than required water-vapor/co2 ratio? Or is that a non-issue?
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