This Scientific American article on energy usage of flourescent lights, answers a question I had heard regarding the power surge of CFL’s (and regular flourescents) when switching them on…
Turns out, however, that power surge is so brief that its energy draw doesn’t amount to much: the equivalent of a few seconds or so of normal operation, according to U.S. Department of Energy estimates. In other words, from a strict energy-conservation standpoint, it’s almost always beneficial to shut off fluorescents when leaving the room—the start-up energy is offset by the power saved in even the briefest outages.
The basic conclusion, turn any light off when you leave the room.
