[nova]

I do remember reading an article a while back about a company in Nevada that has genetically engineered a algae that excretes heavy fuel oil as its metabolic waste product. They said the inserted genese could be tweaked to produce everything up to and including 93 Octane gasoline. Their biggest hurdle is scaling it up to industrial levels and separating the fuels from the algae soup.

If we manage to find a good primary energy source (like nuclear fusion) you can use the energy from that to reclaim CO2 from the air as liquid fuel using selective catalyst reduction. In theory we could all have a machine in the garage that sucks CO2 out of the air to refuel our cars with....