Due to apparent issues when multiple factories are working on assembling a ship, I am using one factory with (2) speed upgrades, (1) construction upgrade, (1) projection upgrade, and (4) power efficient upgrades.
I realize this isn't much building power, but it still requires the majority of power from my (2,000) solar panels.
I've tried other combinations of upgrade modules, but they use too much power; it burned through a Lot of my uranium (hence why I'm dependent on solar now.)

My current connundrum is, why does it take the factory multiple hours to assemble a (large) ship? The nanites are moving rather quickly, they move as a sizable swarm, and the factory has 30+ assemblers at its disposal. And yet it seemingly builds so slowly.
After watching it build block by block for two hours, these nanites seem to be moving pretty slow.
Are the speed modules in need of upgrading, or should I bite the bullet and build more solar panels so I can put more construction upgrades on this factory?