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

Post by xupybd » Mon, May 06, 2019, 11:18 PM UTC

Damorian wrote: post #59

rmcginnis wrote: post #49

Earlier quoted context omitted.

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.

Ah, that certainly explains it. I'm still highly skeptical of how widespread this will ever be, since electric cars will become even more compelling as electricity costs decrease, but you've convinced me to not dismiss this completely as impractical. Thanks for the context.

Post by __d » Mon, May 06, 2019, 11:19 PM UTC

tofof wrote: post #53

rmcginnis wrote: post #35

Earlier quoted context omitted.

First question - each ton of CO2 captured is equivalent to approx. 113 gallons of renewable gasoline. If we replace all fossil gasoline in the US, for example, that's approx. 140 billion gallons, equivalent to approx. 1.2 Gigatons of CO2. You can more than double that for the world. If we include all liquid fuels (including heating), it's larger still. It's a hugely significant CO2 emissions reduction. Second questio…

I believe you misread the first question. It wasn't asking for the numbers on the conversion from CO2 to gasoline; it was asking about the rate at which you remove CO2 from the air. What's the expected total removal per year in, say, your first, fifth, or tenth years of operation?

Post by stordoff » Mon, May 06, 2019, 11:22 PM UTC

icebraining wrote: post #88

berbec wrote: post #76

Earlier quoted context omitted.

Plastics! Zero-carbon plastics would be great. Pull CO2 from the air, mix with water and wind/solar elec and product bags, phones etc!

The thought is kind of horrifying, but you could even make it a closed process - send your old phone to the factory, where it's burned to produce the plastics for your new phone.

Post by alexeldeib » Mon, May 06, 2019, 11:22 PM UTC

dragontamer wrote: post #343

rfrey wrote: post #286

Hi Rob. I'm CTO of a company that generates electricity from waste heat at industrial facilities. Pipeline compressor stations often generate 35MWth+ in waste heat, which we can use at about 20% efficiency to generate electricity. Many pipeline compressor stations are not anywhere close to distribution lines so just merrily pump this heat up their stack. Especially with new pipelines where companies are battling (leg…

> Pipeline compressor stations often generate 35MWth+ in waste heat, which we can use at about 20% efficiency to generate electricity. Can the waste heat be used for distillation instead? To heat up the fuel/water mix to separate the two cleanly? It would seem to me that the future of "waste heat" is to actually utilize the heat, instead of powering a relatively inefficient heat-engine. Perhaps instead of 20% efficie…

Post by rmcginnis » Mon, May 06, 2019, 11:24 PM UTC

__d wrote: post #351

rmcginnis wrote: post #45

Earlier quoted context omitted.

There is no waste. The only inputs are water, CO2, and electricity. The only outputs are fuel and oxygen.

What about dust, pollens, etc, from the air? Is there a maintenance requirement to clean filters or something? Does the efficiency of ingesting the water vapour and CO2 decrease over time until maintenance is performed?