Yeah, the issue is we already need to build huge amounts of renewable/nuclear to replace existing. Trying to also add on carbon -> fuel 'sequestering' just massively increases the amount of energy production required.
One of the 'features' of nuclear power is that it the marginal cost of running the plant at full capacity is low compared to running it in line with demand. That's why the UK have large interconnects with France.
If instead they could turn the excess power production into fuel then I'm sure that'd be a nice side effect.
Solar power has the peak load problem too, though I'm not sure how economically these systems could be built to run a fraction of the time.
It may be a reasonable use after we get a lot of excess peak production but for now the more efficient storage (pumped hydro or battery) is probably the better use of our power. Someone with a better source on the numbers could definitely do the math for which removes more carbon; replacing replacing a nighttime power plant (coal/NG) or replacing some of the fuel supply. I can't imagine the CO_2 -> Fuel process is particularly efficient.
