WordNet (r) 3.0 (2006):

wattage
    n 1: the product of voltage and current [syn: electrical
         power, electric power, wattage]

Moby Thesaurus II by Grady Ward, 1.0:

72 Moby Thesaurus words for "wattage":
   amperage, armipotence, authority, beef, black power, brute force,
   charge, charisma, clout, cogence, cogency, compulsion, dint, drive,
   duress, effect, effectiveness, effectuality, electric horsepower,
   electric power, energy, flower power, force, force majeure,
   forcefulness, full blast, full force, hydroelectric power,
   hydroelectricity, influence, main force, main strength, mana,
   might, might and main, mightiness, moxie, muscle power, pizzazz,
   poop, potence, potency, potentiality, power, power load,
   power pack, power structure, power struggle, powerfulness,
   prepotency, productiveness, productivity, puissance, pull, punch,
   push, sinew, steam, strength, strong arm, superiority, superpower,
   validity, vehemence, vigor, vim, virility, virtue, virulence,
   vitality, watts, weight