[jvanderbot]

You're right (current state of the art), but also wrong (in the spirit of the question as I read it).

If energy prices go down, e.g., from continuing decline of solar, then it may be very cost effective to store energy as hydrocarbons which are synthesized from cheap energy + CO2. E.g., make natural gas from the air and sell it cheaper than it could be extracted and transported.

In this scenario, rather than paying exorbitant fees for CO2, the cheap energy could be used to extract it from the atmosphere where it is abundant.

Before anyone bites my head off - consider the tyranny-of-the-rocket-equation problem of burning gas to transport gas from source (wells, refineries, etc) to consumers. Then consider that the sun shines most places, and CO2 is effectively uniformly distributed. So Synthesis wouldn't have to be cheaper at the source if it can beat the price at the consumer via avoiding huge distribution costs.