Energy efficient light bulbs. Leave them on or turn them off.?

This is a popular misconception. The theory behind this misconception is that the power surge that occurs when you first power on a light will use as much electricity as five (or fifteen) minutes of the regular consumption of the bulb. And since when you turn lights off you have to turn them back on, it's better to leave the lights on than to turn off lights that are going to be needed in the near future.

It's obvious how wrong this is when you think about the implications. Suppose you have a 23-watt fluorescent light bulb. Assume it draws as much in the first second as it normally does in 15 minutes. 23 watts at 120 volts is equal to 0.1917 amps (remember that Watts = Amps x Volts). But since we've packed 15 minutes, or 900 seconds, of that light bulb's energy into that first second, we would have to multiply the 0.1917 amps by 900 to get the amperage consumed the moment the light went on. 0.1917 x 900 = 172 amps, which is a higher level of power than most entire houses are wired for (most have a 100 amp or lower service). So there is simply no way for this assumption to be true. Even assuming the bulbs used just one minute worth of electricity in the second they are turned on would mean 11.5 amps, and many household electrical circuits are only wired at 15 amps. So switching on a light fixture with three 23 watt bulbs would blow the circuit breaker!

Always turn the lights out when you leave a room. Those few minutes may turn into a lot more minutes than you expect, if a neighbor drops by, the phone rings, or you just plain forget. Yesterday I discovered a light on in the basement and no one had been in the basement since the day before that. One time of forgetting to come back and turn off the lights uses far more electricity than you would waste flicking them off and back on, even assuming the story about the power surge was true.

All this explained in more detail below.

I volunteer at an energy exploration center. We do several experiments with various bulbs. I have seen a CFL on a watt meter and it uses about 1/10 or a watt more while it is warming up, since it probably uses 16 watts when in use, you save energy by turning them off. Some take a little time to warm up, so if that dim light bugs you and you are going to be right back then leave it on.

I doubt this is factual, anything using power when turned on should be turned off when not needed. Whether your using energy efficient devices or the older technology, its important to save power and thus reduce the cost on your power bill.

This is not true, turning off an efficient light bulb and turning it on again doesn't change the power consumption of the bulb.

Just realise that its important we are considerate of what products we buy, and how much power we use daily.

apart from fluorescent lighting fixtures, it is going to commonly be a saving shutting issues off (no longer on standby). a controversy would be made for desktops in hibernation or standby the place it would desire to take a shorter time to renew artwork than reload each little thing. some equipment would take a time to heat as much as working temperature and hence value greater to maintain shutting down and restarting. An occasion is oil refineries the place it takes 3 days to accurately close down all and yet another 3 days to come again to familiar use. it is going to likely be greater effective and greater value-effective to run yet at a min cost all of the time. little question persons can furnish many greater examples of this form of element however the genuine answer is = standard shutting down often will save capability.

wrong. That applies to anything with a large inductor, or that has to maintain a large magnetic field (like a cathode ray tube).

Those types of devices take more energy when starting up because they need to rebuild the magnetic field that dissipates after you shut it off.

The new lights just aren't as efficient when they start up because it need to heat up the gas; but they don't draw more power starting up like a TV does.

Just because there energy efficient does not mean that you should leave them on. They still use energy !

don't see the point switching off for a few minutes