Graviton

Required to build Death Stars. 300,000 energy
is needed for developing this technology.
Divide 300, 000 by the number of energy one solar
sat gives. (The lower the number of the colonisation
spot, the higher the energy one sat gives)
This Gives you the number of sats you need to reach
the required energy level. Multiply this number by
2000 and 500 to know the building costs to go for it.
Check the construction time and multiply it with
the number of sats to calculate how many seconds the
cons