Steam all the way
Rare7.4%ObjectiveOptional
Win the game without building any solar panels.
Launch a rocket without ever building a single Solar Panel. Power the whole run on steam (boilers + steam engines) and/or nuclear instead. Easy enough - just never place a solar panel on that save. Mutually exclusive with Solar power and
Solaris, so those are off the table on this run. Best on its own base-game save so one absent-minded panel doesn't spoil it.