Apparatus and methods pertaining to moving a train rig between locations associated with corresponding different wellsites. Equipment carried by the train rig is operable in conjunction with forming wells each extending beneath a corresponding one of the wellsites. An adjustable swing arm mechanically and electrically connected to the train rig comprises a medium-voltage (MV) cable. The adjustable swing arm extends from the train rig to connect the MV cable to one of a plurality of MV electrical hubs each electrically connected to a remote MV electrical power source via, at least, MV electrical lines suspended above the wellsites. A piece of equipment carried by the train rig is energized by MV electrical power delivered via the adjustable swing arm, and then operated in conjunction with the subterranean well formation.