I'm at:

Metal Mine (Level 6 )
Crystal Mine (Level 4 )
Deuterium Synthesizer (Level 4 )
Solar Plant (Level 8 )
Robotic Factory (Level 1 )

Upgrading the Robotic Factory next, then the Shipyard will be fired up.

Something good to know. The position of your planet affects how much energy your Solar Plant produces. #1 being closest to the sun, #12 being furthest away. My planet is smack bang in the middle at #6.