maybe no-one on here says anything, but I've never seen a ps3 folding thread in here and would assume you "may" struggle for an answer
...you watch there will be loads of folding posts now
Anyway to try and answer you question, as far as I'm aware all the ps3 will do is turn the monitor / tv into standby / low power output, the fans may slow down but not a "power saving" mode per se