Lights kept on, or turn off

by Michael
Just a discussion we're having about the cost savings of turning fluorescent lights off when leaving the office. Office has two eight foot twin tubes fixtures. Have been told to turn lights off every time you leave the room, (GO GREEN). My thoughts are, you are killing the tubes, and ballast turning them on, and off 20 - 30 times a day. My contention is, the little bit of money saved on electricity, is far offset by the cost of shortening the lifespan of the tubes, and ballast. Am I correct? Thanks Mike
  12 answers
  • KMS Woodworks KMS Woodworks on Sep 01, 2012
    Myth busters did this some time turned out to be 23 seconds of burn for a fluorescent start up and .36 seconds for an incandescent. does this room lack said during the day....we only use our lights at night when its dark and the windows can not provide some help

  • Z Z on Sep 01, 2012
    Thank you Michael for asking and KMS for finding the Mythbusters clip to prove the answer I've been trying to get across to my family for 32 years now. I try to leave lights off during the day, but we do have a few rooms with out windows that need lights one when in use. Otherwise it's raise those shades, open those drapes around here.

  • 3po3 3po3 on Sep 01, 2012
    Michael, this should answer your other question, about the life of the lights. According to the California Energy Commission, leaving lights on burns out the light faster than switching it on and off:

  • Michael Michael on Sep 02, 2012
    Thanks Steve, I stand corrected, or let's call it enlightened.

  • LandlightS LandlightS on Sep 02, 2012
    Adding an occupancy sensor, either in the ceiling with a 360 degree view or an in the junction box of the light switch with a 180 degree view, is the answer to your problems. Gary

  • Z Z on Sep 02, 2012
    How easy and expensive is that Landlights? I'd love to have those in all rooms in our home. I'm the only one that regularly turns off the lights when not in use.

  • KMS Woodworks KMS Woodworks on Sep 03, 2012
    An occupancy sensor may make sense in a room that lacks windows...but if it turns on the lights every time I walk into a room...all of the "daytime" events would be using power when its not needed.

  • LandlightS LandlightS on Sep 03, 2012's the same as replacing a standard toggle switch with another switch or a dimmer. You can find these occupancy sensors at either HD or Lowes. Look for the control that has a 3 position slide, auto and on. You can than use the slide control to keep the lights on, or operate as auto on/off. These controls allow you to set the "time on" from a few seconds to about 10or 15 minuets(the time that the lights will turn off after no motion is sensed). Additionally, a Vacancy Sensor turns the lights off as you leave the room, but you must manually turn the lights on as you enter the room. Here is a link to Lutron explaining the details.

  • Z Z on Sep 03, 2012
    Thanks LL. If I understand correctly that would work perfectly for us since my guys have no trouble remembering to turn the lights on when needed when entering a room. It's the turning off when they leave that's the problem. KMS, I guess I never thought about that because I figured they'd only turn on when dark. I think we'll be okay by what LL wrote about how the vacancy type work.

  • LandlightS LandlightS on Sep 05, 2012
    Point of info: KMS, all "motion sensors" are actually a PIR sensor (Passive InfraRed) that actually senses the change in temperature of the human body (sometimes a large dog) so the daylight doesn't have any effect during daylight hours. Outdoor sensors flood lights have a "photo-eye" built in to prevent activation during daylight hours. You could prevent the sensors from working indoors in the daylight hours by having a control that allows an "On, Off and Auto" function. You would have to remember to turn the control from "off" to "auto" for motion operation. Have a great day.... Gary

  • KMS Woodworks KMS Woodworks on Sep 06, 2012
    Landlights...too bad they don't make these indoor units with a scaled down version of the photo receptor. With all of those bell and whistles and the added is pretty easy to just learn to turn them off. A few years back I rebuilt a basic motion flood light set with a simple photo cell and a modifed GU-10 LED. The old light ran a pair of 75 watt incandescent floods when "tripped" the new light runs dusk to dawn with a high output 3 watt is more than enough light to let us find the keyhole when coming home after dark and plenty to gather firewood during the winter nights. Plus that LED bulb lasts a LONG long time.

  • LandlightS LandlightS on Sep 06, 2012
    Looks were way ahead of the market, Gary