Given the rapid expansion of solar, and that it keeps accellerating, we're less than 10 years away from seeing a massive decline in demand for gasoline.

I don't know the chemistry, and whether that'll make more hydrocarbons available for creating Jet-A, but I do expect that there will be massive overproduction of gasoline - and if price is left to market demand, it'll drop.

It won't get cheaper than solar though.