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irons31860
Does it use more electricity to turn lights off and on all the time or to just leave them on?

 
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Hi, It depends on the kind of light. If you have fluorescent tubes, then it takes an extra amount of current to kick start them every time you switch on, so it's cheaper to leave them on than to keep switching them off.

However if you have ordinary light bulbs, then it saves the cost of electric power to switch them off when you're not using them-- just like your mother told!

Comments from irons31860:
EVEN IF SAY, YOUR GOING IN AND OUT OF A ROOM ABOUT 8 TIMES IN AN HOUR AS OPPOSED TO JUST LEAVING THEM ON FOR THAT HOUR THEN TURNING THEM OFF?
Journo
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If they are incandescent lights then there is no extra electricity used when you first switch on the light, so turning them off and on again is fine, you are better turning them off each time. If the lights are fluorescent, then they use more electricity at the beginning, each time you switch on, in order to fire up the tube. So turning these off and then on again does use more power. If the light is off long enough to save the extra power used on switch-on, then you save. How long this is is hard to quantify, but a few minutes is safe. The lamps will also fail sooner if they are switched on and off a lot, that applies to all types of lamp.

Tartrazine UK
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If you are constantly starting and stopping a ballast system, it probably makes more energy sense to leave it on. Regular bulbs, however, show minute changes either way so it doesn't matter with them.

mistakenidentity
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