4 ms·

So, you spend a load of energy to reform atmospheric CO2 back into hydrocarbon fuel - and then just burn it again, turning it back into CO2 and putting it back

by dflock 7y ago

So, you spend a load of energy to reform atmospheric CO2 back into hydrocarbon fuel - and then just burn it again, turning it back into CO2 and putting it back into the atmosphere? The end state of the atmosphere is, at best, the same as the starting state, but you've expended a load more energy for nothing. If the energy to run this process isn't zero-carbon, then this is going to be a big net emitter when done at scale. This is just creating green-washed gasoline.

maerF0x0 7y ago
not if the initial energy source had a lower CO2 impact than normal gasoline. eg: The Gas making machine used solar or wind for input . Now, I dont see the point over just using electric cars, but i guess this has a limited shelf life for those existing cars, or those who refuse to change?
- azernik 7y ago
  Could also have continuing niche uses where energy density is paramount, like aircraft/rocket fuel and portable generators. e.g. the US military has been looking at biological or synthesized JP-8 substitutes for a while, for supply-chain risk reasons instead of environmental ones.
jsonne 7y ago
You don't have to burn it. In theory governments or environmental groups could simple buy and store it.
- lolc 7y ago
  Or turn it into plastics which is more useful.
- dflock 7y ago
  If you're not going to burn it, you should turn it into something else - carbonate rock, ideally.
snowmaker 7y ago
It depends on the alternative state of the universe. If the alternative state of the universe is you never drove the car, then you're right, this is not clearly better. If the alternative state of the universe is you drove the same car but burned gasoline that was drilled out of the ground, then this is much better.
- dflock 7y ago
  If you have a mechanism that can extract atmospheric carbon, at scale, without any additional emissions (which isn't really what this is...), then that carbon needs to go back into the ground, not back into the atmosphere. We don't _just_ need to stop carbon emissions, we need to get the atmosphere back down to ~250ppm, from the current ~412ppm - we probably can't afford to wait ~two centuries for it to weather out naturally.

by dflock 7y ago

maerF0x0 7y ago

not if the initial energy source had a lower CO2 impact than normal gasoline. eg: The Gas making machine used solar or wind for input . Now, I dont see the point over just using electric cars, but i guess this has a limited shelf life for those existing cars, or those who refuse to change?

azernik 7y ago
Could also have continuing niche uses where energy density is paramount, like aircraft/rocket fuel and portable generators. e.g. the US military has been looking at biological or synthesized JP-8 substitutes for a while, for supply-chain risk reasons instead of environmental ones.

jsonne 7y ago

You don't have to burn it. In theory governments or environmental groups could simple buy and store it.

lolc 7y ago
Or turn it into plastics which is more useful.
dflock 7y ago
If you're not going to burn it, you should turn it into something else - carbonate rock, ideally.

snowmaker 7y ago

It depends on the alternative state of the universe. If the alternative state of the universe is you never drove the car, then you're right, this is not clearly better. If the alternative state of the universe is you drove the same car but burned gasoline that was drilled out of the ground, then this is much better.

dflock 7y ago
If you have a mechanism that can extract atmospheric carbon, at scale, without any additional emissions (which isn't really what this is...), then that carbon needs to go back into the ground, not back into the atmosphere. We don't _just_ need to stop carbon emissions, we need to get the atmosphere back down to ~250ppm, from the current ~412ppm - we probably can't afford to wait ~two centuries for it to weather out naturally.