Re:Catching CO2 from trucks and reducing their emissions by 90%
by karmakaze on Tuesday December 24, 2019 @06:41PM
(#21875684)
One reason why it should be much more efficient in energy expended for CO2 captured is that the concentrations from the truck exhaust is so much higher than in the atmosphere.
Re:Catching CO2 from trucks and reducing their emissions by 90%
by AnimalMuppet on Tuesday December 24, 2019 @09:07PM
(#21876240)
On the other hand, a central facility can often be more efficient (other things being equal) than a bunch of small facilities. (A central generating facility, for example, is more efficient than a bunch of car engines.)
That said, my money is on the higher concentration of CO2 winning by far.
Re:Catching CO2 from trucks and reducing their emissions by 90%
by catalogia on Tuesday December 24, 2019 @10:04PM
(#21876483)
> They use the heat from the exhaust gases to power the device, the calculations are in the paper.
Wouldn't this effect the efficiency of catalytic converters? As I understand it, those need to be hot to work well. Or is the heat taken out of the exhaust after it passes through the cat? Skimming through the paper, I don't see mention of this.
Maybe it would make sense to shrink the engine's radiator and use some of the engine heat instead of exhaust heat.
They don't use the collected CO2 to make diesel fuel, they make methane. Some trucks may use methane as fuel.
IIUC they don't expect every gas station to have a converted from CO2 to fuel, but to have the conversion in the operational bases of the trucks, or collect it and send it to a specialized facility.
They use the heat from the exhaust gases to power the device, the calculations are in the paper.
They say that in other projects, they use the same heat of the exhaust gases to improve the efficiency of the fuel in a 10%. So this is not totally "free".
How does this compare to releasing the CO2 (and getting a 10% of efficiency) and collecting the CO2 from the air in a central location?
How does this compare to using Hydrogen as fuel? I guess the difference is that most of this technology is buildable now, but Hydrogen storage is too difficult for now.
How does this compare with a electric truck? I guess this system gives more autonomy, but all the chemical reactions to convert the CO2 to methane are less efficient that good batteries.