There's no pollution past transition because the energy would come from wind, solar and or nuclear or other such renewables.

Renewables don't burn anything and nuclear only produces small quantities of waste. Specifically the new fusion reactors will produce no or much reduced waste. There's no C02 involved at all.

Realize that all of the sun energy is actually wasted. It literally just passes thru the planet every single day. All we do with solar is play with that energy by slowing its departure a little more than usual. Eventually the planet just gives it off to the rest of the universe via heat and other electromagnetic emissions. Further more, the sun is way larger than earth and it emits light that will never actually reach us. We are but a tiny sliver of all the sun's emissions. The rest of that power is just given off to the universe. Solar power is thus a permanent source that we can use specifically for transportation... Electrical or hydrogen. The question of inefficiency only has any meaning when comparing.