Heh.. dude, I know You know the tanker needs fuel, but is Your character aware of it? or did you simply waltzed into the emperor room and wanted to perform magic of sending the fuel somewhere, but God knows where.. Simply put there are a few ways that i know of to get to know that the tanker needs fuel.
#1 go to the ExxonValdez's bridge and speak with the Capitan. Hell tell you what needs to be done..
#2 go to the ExxonValdez's bridge and consult the ship's main control computer.
further more I'm not quite sure, however as part of RP it may proove nessecary to search for other means of supplying the tanker with fuel. I think the Emperor one was cut..
the ones i know of:
#1 gather 3 torn password papers, and search a suitable computer console away from any npc that may spot you tampering with it. use the password for chemistry station and divert fuel to tanker.
#2 provide chineese researh team with a suit of Hardned Power Armor in exchange for the fuel..
#3 finish all the quests for the Shi
#4 rescue Badger's girlfriend ( Badger gets wasted when you return from the platfirm)
#5 if you diverted the fuel from the shi to hubbologists first, you may still use Badger's servides ( i think), or ask Crokett, if you tell him ASH5 Vicky Goldmann made fun of him, or do it yourself if you sneak access the console in crockett's room ( asuming you haven't accessed it eariler and robbed the hubbologists stash afterwards)
I assume the emperor fuel transfer was cut because it was lame to begin with, You'd be given the chance to ask for fuel even before meeting the emperor the proper way, and you weren't sepose to get access to the emperor before that anyways ( superstimping the guard and or stealthboying inside does not count as a reasonable way to get in, as this is seposed to be super guarded place).