Do you factor the carbon that went into producing the solar panels and wind turbines?
Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline
481–490 of 589 posts
Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline
#482Earlier quoted context omitted.
* producing solar panels and such also requires energy input, and these do have limited lifetime. What is the real full-cycle energy conversion ratio is? I wonder what this is, too, but a typical 300W panel with 20 year lifespan will generate something like 20MWh over its lifetime. You can't possibly use anywhere near that much energy to manufacture it.
I read something about this a little while ago - if I recall the analysis correctly the energy payback was in the order of 1-2 years for the average (300W or so) panel. Not bad for a 20 year life, but we will need recycling advances in the meantime as we will have so many panels reaching end of life in the next decade.
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Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline
#483How 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…
who is paying $7/gallon for gas? In the UK, people pay approx $6 per gallon for gasoline.
In France current prices are around 7$/gallon (1.6€/L)
Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline
#484The 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…
So we bleed energy off a hydrocarbon fueled generator system that produces CO2, to power a machine for capturing CO2 to create hydrocarbon fuels. That seems a little pointless.
The advantage of this system is you can use excess renewable energy sources to mitigate hydrocarbon energy generators. If you are running a hydrocarbon powered system, don't use energy to power this capture system at the same time. That's madness. Better to use that energy to reduce your use of hydrocarbons in the first place.
Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline
#485> 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?
USNRL have achieved ~50-60% efficiency using similar technology -- though sourcing from seawater rather than air.
Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline
#486The Navy would be highly interested in this, as they've had a project in the works for years (via NRL) to create jet fuel from seawater. They're basically 25% efficient right now, and the physical size of the device vs the output is quite prohibitive... But the advantage of making jet fuel on the carrier itself for the planes, by using onboard nuclear vs having to dispatch and maintain a fueling fleet is quite attrac…
A compilation of references going back over 50 years, at USNRL, MIT, and Brookhaven NL.
https://old.reddit.com/r/dredmorbius/comments/28nqoz/electri...
Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline
#487A few questions from a chemistry major 1. why extract from the air when you can just put a device on the smokestack of an existing coal or natural gas plant? The higher CO2 density of the effluent will make things more efficient. 2. Your key innovation isn't the part where you pull CO2 out of the air; it's the nanotube-based reverse osmosis process for separating ethanol from water. This process could just as easily…
> 1. why extract from the air when you can just put a device on the smokestack of an existing coal or natural gas plant? The higher CO2 density of the effluent will make things more efficient.
That was my big question, too. Asked and got a response here:
Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline
#488Earlier quoted context omitted.
"why extract from the air when you can just put a device on the smokestack of an existing coal or natural gas plant? " The process uses clean electricity to reverse the CO2. I suspect here we have a timing issue. When the sun shines, the gas plant will be idle, and that's when the spare electricity is available is used to reverse the process. And the physical position - the gas plant is likely to be where the sun shi…
The co2 could be stored underground? I guess that could deal with the timing issue at least?
You're mostly right, in that a timing issue could be resolved through a temporary storage unit, though probably wouldn't have to put it underground.
Likewise, batteries/capacitors/whatever would probably be set up on the electricity. A plant design would seem to want to control the flow rates of both.
Overall, the parent comment's unlikely to be correct in its speculation that the reason for open-air capture is related to timing issues.
Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline
#489Can you hook a miniaturized-enough version of this device to your exhaust pipe then and have a zero exhaust car that runs on water but is technically a gasoline car?
Re: Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline
#490The 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…
If this new process is working at scale, it has huge potential. I just wonder whether this process is covered by a patent or not. Might be a huge risk if not. If so, I wouldn't be surprised when the new process is named after the inventor. Much like the Haber-Bosch process.