On Aug 18, 1:06 pm, Andy Burns wrote:
On 18/08/2007 18:59, Marsbar wrote:

Switch on only when required. What made you think that switching a
fluorescent light on and off wasn't a good idea?

It was either a common misapprehension, or used to be different with
older tubes. I certainly remember an "order" going around school in the
early 70's to NOT switch off lights during break-times as it took more
electricity to re-start them, than to leave them on for 20 minutes.

In the case of CFL's I recall that while they do take more energy on
start-up, the break even point comes after a matter of a few seconds.
So, for practical purposes, they should be turned off when not
needed. With all of the ones I've seen, the bigger problem is what
was already noted. They take a couple mins to reach full output.
Even worse, the output is terrible for the first 30-60secs. For that
reason, I leave them on more than I would a regular light, thinking
I'll need it again in maybe 10 mins. But overall, I'm pretty sure
I'm saving a good bit on energy.