After a plane burns all its jet fuel to fly where it is going, we will have to expend even more than that much energy to suck the C02 out of the air again.
Flying will cost at least 2x as much as it does today.
Flying will cost at least 2x as much as it does today.
Fuel accounts 30-50% of the costs of air travel. A straight doubling of fuel costs would not double air travel costs (although it would hurt)
The CO2 emitted from air travel wouldn’t necessarily need to be converted back to a very high energy molecule like jet fuel. I’m not a chemist, but I’m pretty sure there are polymers that you can bind the carbon into and not be nearly as energy intensive as recreating petroleum molecules.
Finally, wind and solar electricity generation are already generally cheaper than any fossil fuel generation besides nat gas. The EIA (via Wikipedia) had that at around 2x cheaper solar versus diesel generation, and solar and wind continue to see cost improvement.
All that being said, any carbon elimination scheme is going to have a cost, but the theoretical cost efficiency can be much better than if you assume energy is 1-1 with cost.
Flying will cost more, but not necessarily 2x more.
Plus that's only if we can't synthesize jet fuel from all that CO2 we're extracting from the air.