Energy Tap

Acquisition
Skill Quests: Skill Trainers who will teach this skill before it is unlocked:
 * Prophecies
 * Helping the People of Ascalon (Old Ascalon)
 * Factions
 * Lo Sha's Gift (Kinya Province)
 * Prophecies
 * Captain Osric (Yak's Bend)
 * Dakk (Ember Light Camp)
 * Factions
 * Zytka (House zu Heltzer)
 * Nightfall
 * Tohn (Kamadan, Jewel of Istan)

Energy Gain
This presumes Energy Tap is cast as often as possible (activation + recharge time) before any activation/recharge time modifiers.

Related skills

 * Energy Drain (Elite)