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

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131–140 of 589 posts

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

#132
post #68

Earlier quoted context omitted.

ICE cars cant compete with convenience of: * not needing to refuel * less maintenance needed * not spewing particulates in air etc (if you care about what you breathe)

Bizarre comment. Being able to quickly refuel is one of the key advantages internal combustion engines have over electrics.

If the ev car companies got their shit together, they could have used swappable battery packs.

You can wait around for 12h to charge, or you can turn in your cores and pay for 100% capacity batts now. And the swap would be quicker than standing around filling up a tank.

But no. Each ev is different and proprietary. The chargers aren't even the same.

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

#133
Hi Rob, Great idea! I have ton of questions:

1) If you hope to target low cost renewable power, will you be operating intermittently at peak production, or around the clock?

2) Does negative pricing of power factor in to your business model?

3) Do you think your process could economically compete in the market for grid energy storage? I so, how does the costs and efficiency compare to other methods?

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

#134

So, the goal is carbon-neutral gasoline. Short term, I suppose your target is feel-good gas burning vehicles. Longer term, do you envision this technology being used for clean(er) + carbon neutral municipal power generation, or is the fuel type just wrong for that? I ask because a stop-gap can easily become permanent, and it'd be unfortunate to continue dumping particulates (pm2.5/10), smog, etc into the air in major…

In the near term, we will remove the damage caused by fossil fuel use. Our fuel will burn much cleaner, so that's also helpful. In the medium to long term, cars will switch to electric, but now we'll have enough time to do that. As that happens, Prometheus will roll out new products made from CO2, like carbon negative building materials, etc. It's important to look not only at the end goal, but also the path!

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

#135
post #120

So what happens to the gasoline afterward? This seems only useful if you bury it underground in an attempt to reverse climate change. If you just use it for fuel, then is this anything other than a really inefficient electric car?

You could stop extracting oil from underground and just keep the existing quantities of CO2 that currently exist. This would allow a "green" application of all the existing engines (think ships) and many situations where going full electric may be impractical.

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

#136

> we expect 50-60% overall efficiency at maturity What efficiency are you at now and what happens to your startup if you never reach that "maybe too optimistic" 50-60% goal?

That's gold, considering where solar cells efficiency are now (mature industry!!)!!

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

#137

Earlier quoted context omitted.

The main advantage of renewable gasoline over batteries is that we can decarbonize the existing vehicle fleet without replacing it. Also, the very high energy density of gasoline, diesel, and jet fuel will make sense for a long time in Jet aircraft, long haul trucks, and ocean container ships, for example.

The very high density is in hydrogen - actually.

And the best way to store hydrogen is to attach it to carbon atoms.

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

#138
Here'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, you're basically diverting renewable energy capacity from consumers. Instead of getting 1kWh of usable energy from a solar panel, they're getting at best 0.5kWh, albeit in a much denser form that's easier to move around for some transportation uses, such as aviation. But, in the short term, you have a net-negative impact.

In the long term, if things keep going where they are going and we end up having to remove carbon from the atmosphere to reverse some effects of global warming, why would we want to convert it into gasoline instead of e.g. just capturing it and storing?

Or is this just a way to generate jet fuel for planes of the future when we'll electrify all of transportation except for flying?

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

#139
post #108

I'm skeptical, but fascinated by what you're doing. It sounds like all of the steps of your process are known, except: 1. CO2 fixation uses only electricity - no natural gas or other fossil fuels. It works at room temperature. 2. Distillation of the immediate products (alcohols) is not necessary. A carbon nanotube membrane solves the problem at room temperature through reverse osmosis. Correct? If so, then why target…

We could use the alcohols as fuels directly (in flex fuel vehicles), but this wouldn't address the much larger market for gasoline. It's a simple and inexpensive upgrade, so makes sense to do it. We will definitely take advantage of carbon credits, tax incentives, etc too!

If the alcohol upgrade to gasoline makes sense technically and economically for you, why is it not commonly done with (presumably much cheaper and extant in great volume) industrial alcohol today?

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

#140

Hi Rob, Great idea! I have ton of questions: 1) If you hope to target low cost renewable power, will you be operating intermittently at peak production, or around the clock? 2) Does negative pricing of power factor in to your business model? 3) Do you think your process could economically compete in the market for grid energy storage? I so, how does the costs and efficiency compare to other methods?

We are designing our systems to run intermittently, to match the intermittent availability of renewable power. The capital cost of our systems is expected to be low enough for us to run profitably even if we are only operating 50% of the time. We expect we will get very low electricity prices because of this, and even negative pricing some times. We are not positioning ourselves as grid storage, but having our systems on the grid will balance demand for renewables, allowing more to be deployed, which is a similar service. If we can get paid for demand response, we won't turn it down!
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