-( Story related, cannot be missed )-
The Power Dome itself is a series of shafts locked with shutter gates preventing the elevators from ascending/descending. It is your job to go between the shafts to break the generators. There are three primary generators to destroy, but in order to get to all of them you will end up having to break another as well. The power stations are docking ports with crystals thrumming with electrical energy and can be either destroyed with an attack or pulled off with your vacuum.
Be sure to spend the time to upgrade your shielding ability while in this area. Several laser grids can be bypassed earlier on by having access to the forward/backward (360 degree) shielding.