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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

#311

Post by rmcginnis »

0000011111 wrote: post #307

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. H…

The smallest scale at which we can operate profitably is probably in the 100,000 gallon/year range, although that could go down over time. We will make modular, mobile systems that don't have to be very big to be profitable. One shipping container will likely be able to do 100,000 gal/yr for example.

The electricity required will be approx. 60 kWh/gallon.

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

#312

Post by inflatableDodo »

rmcginnis wrote: post #290
inflatableDodo wrote: post #246

Earlier quoted context omitted.

Yayy, a mystery. I like mysteries. Could you elaborate on where you could elaborate?

The best catalyst for CO2 conversion is copper. There are papers that have done an exhaustive analysis of alternative metals, and copper comes out on top everytime. Adding it to other materials like carbon or other metals in a heterogeneous material can help with Faradaic efficiencies. We are less concerned with Faradaic efficiencies than overall efficiencies and costs, which leads us to different optimizations than…

Think I got it, your aim is going to be whatever gives you the overall highest specific energy of the outputs for a given combined cost of inputs, rather than any chasing purity of chemical, as they can all be used. That's presumably the rest of industry's problem and it is already setup for that.

edit - also, thank you very much for taking the time to reply to my blatant attempt to work out exactly what you are up to, I really appreciate it. Is a subject I find fascinating.

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

#313

Post by aj7 »

rmcginnis wrote: post #49
Damorian wrote: post #19

How could the math possibly work out on this? If a gallon of gas holds 33.70 kWh of energy, and you can get cheap electricity for $0.1/kWh, you're looking at $3.37/gallon if you have a magical process that converts with 100% efficiency. Even if you hit your efficiency goal, which would be impressive, who is paying $7/gallon for gas? Just buy an electric car. This can only possibly be useful when all of the oil is gon…

We expect a gallon of gasoline to require approx. 60 kWh of electrical energy. If the price of that electricity is below 5 cents, the economics work. If the price is lower, the efficiency of the conversion could also be lower if that optimized other costs (like capital). Electricity is routinely below 5 cents now at utility scale (wholesale), which is where we will want to be.

No the economics does not work, if you include the "externalities" of that gallon of gas. You are continually creating waste heat and carbon emissions, while using naive reasoning based on Gas Buddy prices.

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

#314

Post by JudgeWapner »

rmcginnis wrote: post #24
JudgeWapner wrote: post #16

how many watts today is required to produce one liter of fuel using both your membrane and the conventional way requiring distillation? What are your long-term watts/liter targets ? Maybe a non-membrane version could be attempted that used renewable energy (sunlight) to do the boiling? Certain geographic regions might have the right combination of plentiful sunlight, water, and wind to minimize all these costs?

It will take approx. 60 kWh/gallon of fuel, or just under 16 kWh/Liter. As long as this electricity is from zero carbon sources and is inexpensive enough, it works. Distillation and other thermal processes typically need to burn fossil fuels. The difference between renewable electrical energy only vs using thermal is really more a difference of kind than of degree. It's really hard to do a thermal process that is tru…

how much energy is spent pulling CO2 out of the air? I know this sounds like a step backward, but perhaps burning plant matter or recycled cardboard might be a more efficient source of CO2? If purifying smoke is cheaper (energy-wise), maybe you could let mother nature extract the CO2 through fast-growing plants, then dry and burn them?

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

#315

Post by wbl »

ossie wrote: post #126

The unit economics around this are by no means perfect but the BIG point here that should probably be in all caps is that fact that the thermal process is displaced by the use of electricity. We could argue on what is used to generate said electricity, but that is beside the point since this innovation opens up many more possibilities than are stated here. We could also argue about the comparative cost of produced en…

Thermal heat is low grade compared to electricity.

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

#318

Post by sampo »

holy_city wrote: post #58
docker_up wrote: post #29

Earlier quoted context omitted.

Don't skate to where the puck is, skate to where the puck is going to be. Electric cars can't compete against gasoline cars until the price hits about $6/gallon. And considering that crude prices are relatively low, but gas in CA is almost $4/gallon in the Bay Area, it doesn't take much time for normal rates to hit $6/gallon in the next 10 years or so. At that price, it becomes more economic and that's the time frame…

> gas in CA is almost $4/gallon in the Bay Area And the national average (today) is $2.95, you might as well compare Hawaii and Alaska which are also economic islands. >it doesn't take much time for normal rates to hit $6/gallon in the next 10 years or so. The national average 10 years ago was $2.45, which is $2.90 accounting for inflation. The only way gas hits $6 is if we have a second Great Inflation or massive po…

Gas is currently about 1.56€/liter ($6.6 per gallon) in Finland.

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

#319

Post by Timothycquinn »

How sensitive is the systems to airborne sodium chloride if located near salty bodies of water? I would assume that colocation with nuclear power would be ideal and many nuclear plants are next to salty bodies of water.

Being an energy auditor in my early career in the energy sector, I'm very interested in seeing such systems implemented to balance system loads during off peak times which will make Nuclear (safe and well designed) more cost effective.

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

#320

Post by _Nat_ »

Why open-air capture?

I mean, it's typically much cheaper to capture CO2 from concentrated streams, such as the flue gases from coal-fired power plants. So why accomplish the same CO2 mitigation at higher cost by getting it from open-air capture?

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