I'm one of those folks who goes around turning lights out in empty rooms. I was accosted at my workplace by someone who claimed that it was ineffecient to turn CFLs off and on several times during the day because they need to warm up each time they're turned on. Can anyone send me information on this?
Thanks,
Helen
Helen Venada
San Juan County Solid Waste Division
P.O. Box 729 Friday Harbor WA 98250
360-370-0503
This is an old thread, but I think you may have reached a misleading conclusion.
For starters, I question the Mythbusters comparison of a 10-watt CF bulb to a 90-watt incandescent bulb. The most optimistic manufacturer's claim I found to substitute for a 90-watt incandescent is a 23-watt CF bulb. This is 2.3 times as much energy usage as Mythbusters alleges. (In my opinion, Mythbusters values sensationalism over accuracy; they are a TV show, not a scientific laboratory.)
I also note a subtle but crucial factor--you describe saving *energy*, while most people are interested in saving *money*. The key difference is the cost of replacement light bulbs. The Lighting Research Center at Rensselaer Polytechnic Institute found that the lifespan of a CF bulb is profoundly impacted by how often it is turned on and off. In their tests, a CF bulb on a 5-minute switch cycle lasts only 15% as long as its rated hours. So if you typically use a CF bulb for 5 minutes at a time, you'll use seven times as many bulbs as the package claims--and that adds up to a lot of money! LRC used 440 bulbs in their test, under laboratory conditions described in the report. As you describe it, Mythbusters seems to have used a sample size of just 1 CF bulb--apparently without even a control CF bulb for comparison. From my knowledge of statistics, it's impossible to extrapolate a comparison with an uncontrolled sample size of 1, but Mythbusters somehow does so to arrive at their sensational "busted" conclusion.
So while you will obviously save energy by turning off a compact fluorescent bulb when you leave the room, it may cost you money! And I'm not sure Mythbusters is doing anything but generating more myths.
I suggest you consult the Lighting Research Center's detailed testing results here: http://www.lrc.rpi.edu/nlpip/publicationDetails.asp?id=114&type=1 -- see "Specifier Reports: Screwbase Compact Fluorescent Lamp Products", a 79-page free PDF listing their extensive lab results.
Best regards,
-Tom Jones
Tom Jones
United States