Depends on where you are! On Mars, for example, it's going to be far more cost effective to get carbon from the Martian atmosphere and water from the subsurface than to ship carbon feedstocks from Earth.
Currently, these technologies are approaching parity on cost fairly quickly. It's basically at the prototype stage presently, so much more expensive, but widespread adoption and economies of scale could change that within several decades. The upfront costs are quite high, similar to any petrochemical complex, i.e. in the multi-billion-dollar range for any facility capable of significant industrial-scale output.
> Currently, these technologies are approaching parity on cost fairly quickly. It's basically at the prototype stage presently, so much more expensive, but widespread adoption and economies of scale could change that within several decades.
Sorry, but how could that possibly work from even a first principles perspective? Oil is literally just pumped out of the ground, whereas you have to overcome the entropy of highly disperse atmospheric CO2, and then you have to add the enthalpy of the hydrocarbons!
But then, you have to distill it and strip out the sulfur and other elemental contaminants and fractionate it and crack it... one benefit of starting off with pure CO2 and water is the ability to selectively make pure hydrocarbon fractions (or at least fairly restricted spreads of chain lengths) without having any waste.
Also, there's the distribution issue - this could all be done regionally, so transport costs will go way down. The only thing needed is excess energy to dump into the process (equatorial zones would be good for solar PV inputs, etc.)
Currently, these technologies are approaching parity on cost fairly quickly. It's basically at the prototype stage presently, so much more expensive, but widespread adoption and economies of scale could change that within several decades. The upfront costs are quite high, similar to any petrochemical complex, i.e. in the multi-billion-dollar range for any facility capable of significant industrial-scale output.