The Power Plants draw less than many believe, but it is a consideration and one of the reasons why I've never been completely comfortable owning one, although I do (I also have a Hydra).
The Power Plant 300 draws about 40 watts with nothing connected to it, about 43 in multiwave mode. My Pass Aleph 3 draws around 200 watts at idle (196 acutally, although I think the Pass docs say 250). Plugged into the PS Audio, the total draw is just under 300 watts. Which suggests that there is some additional overhead in there somewhere (more than 200 + 40), but not a doubling as some reviewers have suggested. By the way, I don't normally have the Pass amp plugged into the Power Plant; I just used it for this measurement.
The Power Plant 300 draws about 40 watts with nothing connected to it, about 43 in multiwave mode. My Pass Aleph 3 draws around 200 watts at idle (196 acutally, although I think the Pass docs say 250). Plugged into the PS Audio, the total draw is just under 300 watts. Which suggests that there is some additional overhead in there somewhere (more than 200 + 40), but not a doubling as some reviewers have suggested. By the way, I don't normally have the Pass amp plugged into the Power Plant; I just used it for this measurement.