Does Alien Fuel Refinery count as having a trade power in Race for the Galaxy?
It does count. The Alien Artifact rules actually cover this!


  Consume powers, such as Trade League’s power, can be used. 
  Trade League and Wormhole Prospectors do score for this world.


Similarly, the Brink of War rules explicitly state that Trade League does score for the can't sell power of Alien Oort Cloud Refinery (bottom of page 13)