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

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

#281

Post by s3graham » Mon, May 06, 2019, 9:49 PM UTC

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…

That's very US centric though. It's already much higher where I live (Vancouver, just minutes from the US border): $1.70 CAD/L ~= $4.80 USD/gal. I don't think $6 is far off at all in many locations.

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

#282

Post by rmcginnis » Mon, May 06, 2019, 9:50 PM UTC

thereisnospork wrote: post #185

If you really think the underlying economic problem with electrochemical CO2 to alcohols as fuel is the separation at the end you are in for a world of (economic) hurt. Not that improving the aforementioned separation isn't useful or valuable, its just not the lynch pin. Take a really hard look at your economics, in particular throughput and capital amortization (which scales proportionally to uptime!). Good comparis…

The separation itself is not the only thing that makes the economics favorable. It's important that changing the separation makes the process electricity only overall, and this is a big deal. We can run intermittently, allowing low renewable power costs, and since there is no pressure or heat in the system, we can use inexpensive components. When the capex is low, it allows for a lot of other things to not be ideal starting out. Current densities aren't going to be as high as water splitting electrolyzers or aluminum production, for example, but that's ok in this context.

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

#283

Post by rmcginnis » Mon, May 06, 2019, 9:50 PM UTC

hart_russell wrote: post #280

I hope this becomes an immense success. Gives me hope for the future.

Thanks!

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

#284

Post by robocat » Mon, May 06, 2019, 9:51 PM UTC

progval wrote: post #220

My most immediate question (after others you already answered in this thread) is about getting enough CO2. When you start absorbing CO2 from the air, won't the CO2 in the neighborhood be depleted very quickly? And I'm assuming you can't pump enormous amounts of air either for various reasons (noise, energy usage, other environmental issues). Of course there's wind to bring more CO2, but I'm curious about your computa…

CCS: large amounts of high quality concentrated CO2 from gas fired electricity can be stored underground https://en.m.wikipedia.org/wiki/Carbon_capture_and_storage

And when power prices are low and the gas fired plant is turned off, you have a transmission system right there ready to deliver power.

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

#285

Post by maelito » Mon, May 06, 2019, 9:52 PM UTC

rmcginnis wrote: post #205

xtorol wrote: post #194

Can you elaborate on "we use zero-carbon electricity"? How far abstracted from electrical generation are you? What guarantees do you have that your electricity is provided by low/zero-carbon sources?

We're going to take the power at the renewable power plant, so we will be certain that we are getting zero carbon electricity.

Solar panels or wind turbines do emit CO2 (e.g. construction, maintenance). Is the amount of CO2 emitted per kWh negligible compared to what would be captured from the air ? What's the ratio ?

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

#286

Post by rfrey » Mon, May 06, 2019, 9:52 PM UTC

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 (legitimate) environmental concerns, there is no reason they would not install your tech, powered by a heat recovery system, on every single proposed compressor station on the line.

We have actually modeled it with negative operating costs (using technology from one of your competitors) and think we could get the pipeline companies or the government (we're in Canada) to pay for it even in the face of bad economics. If your system is a step change in effectiveness from those systems, it could be a game-changer in this market.

Let me know if you'd like to explore this a bit. My email is in my profile.

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

#287

Post by rmcginnis » Mon, May 06, 2019, 9:52 PM UTC

jacobush wrote: post #166

rmcginnis wrote: post #107

Earlier quoted context omitted.

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.

Please think twice about diesel - NOX is a killer. On the other hand, I expect particle emissions to be much lower with your fuel.

Much lower particle emissions is what we expect. Also no benzene, sulfur, or aromatics. Despite diesel's drawbacks, I'd rather offer zero carbon diesel as long as people are still using it.

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

#288

Post by lutorm » Mon, May 06, 2019, 9:54 PM UTC

rmcginnis wrote: post #219

lutorm wrote: post #200

This is a cool project! One question though: why is getting rid of thermal processes an improvement? If you're getting electricity from solar, you can get even more thermal energy from solar since the conversion efficiency for capturing heat is much higher.

The cost of solar and wind electricity is low and getting lower. SImilar investments have not been made in renewable heat (like geothermal or solar heat), so they are not as inexpensive. Also, a thermal process needs to run continuously (24/7 if possible), whereas a pure electric process can run intermittently, which is a better fit for the zero carbon energy resources.

I'm thinking of something like http://www.absolicon.com/, concentrating collectors for industrial process heat. Maybe the intermittency is a factor though, you'd need a thermal storage to go along with it.

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

#289

Post by owenversteeg » Mon, May 06, 2019, 9:55 PM UTC

harpastum wrote: post #43

Grustaf wrote: post #4

So you are competing with batteries? I suppose batteries have much higher roundtrip efficiency, but maybe there are other advantages to your technology, like being able to rely on combustion engine cars?

The energy density of gas makes it incredibly useful for storage and transportation as well. For example, Tesla's 50MWh battery installation in Australia has the same energy as only 1,500 gallons of gasoline. (It's not an apples to apples comparison, I just wanted to give an example of a "large" battery installation.) Obviously there are lots of benefits of batteries over gas, but being able to load up a standard 10,…

Yup, exactly. You can fit the entire battery installation in 5.5 cubic meters! A fairly small closet, even (1.4x1.5x2.5 meters for example, 4.5 x 5 x 8 feet) could fit the entire battery plant, which is huge by comparison.

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

#290

Post by rmcginnis » Mon, May 06, 2019, 9:55 PM UTC

inflatableDodo wrote: post #246

rmcginnis wrote: post #239

Earlier quoted context omitted.

Not using nanospikes, but there are many proven heterogeneous catalysts now that can do the same job. Can't elaborate here, sorry!

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 academic labs pursue - they typically want very high specificity. We don't care as long as it burns in an engine well :)