Myth Buster: Leave lights on? Or turn them off and back on again?

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If you pay your own electric bill for your house or apartment, this will be of interest to you.

We all know that leaving the lights on in your house or apartment costs you money. Light's on, electricity is used, you pay for the electricity. Light's off. No electricity. No pay. No surprise there. As a result, we play the game of turning them off as we leave the room to conserve energy and help keep our electric bill down. But you may be Curious to know: Does it costs less in the long run to leave the light on for another minute or two while you scramble from your bedroom to the bathroom and back in the morning while you get ready for work? Or should you ALWAYS turn out the lights when you leave a room, even if you'll be back there in a minute to turn the light right back on? Because how much does that surge of electricity that turns the light on and off cost?

Does the surge cost more than leaving the light on
for ANY amount of time, no matter how short?

I had a boss back in college that ran a huge restaurant with hundreds of lights and many lightswitches. He would yell at anyone who would turn on his restaurant lights on the side of the restaurant that was not in use during the winter. He would tell me that it cost him a lot of money just to turn the lights on and off, more money than it would cost to keep them for x amount of time. So I am begging the question… In the morning is it more efficient to leave your lights on for a few minutes as opposed to turning them on and off repeatedly as you move from room to room? Now I am talking an extra few minutes here and there, not 45 minutes or a few hours.

Apparently, the answer is not a simple yes or no, and the reason for this "maybe" is it depends on the type of bulbs you buy: normal or energy-saving? You want to utilize all types of light bulbs in a way that will help you save money and save energy. Energy saving light bulbs that are a little more expensive but save you the money in the long run take a while to warm up and achieve maximum brightness. So flicking that light on and off isn't really effective in achieving your desired lighting in a bathroom, for example. So its best to only use them in rooms where they stay on for longer periods of time, like a living room. Having said this, it's best to use normal light bulbs in high traffic areas where you'd be flicking the switch on and off frequently.

So back to our question, but with the caveat that we're only talking about normal lightbulbs here: Is it better to turn off your lights every time you leave the room even though you'll be back in two minutes, or should you just leave them on for a few minutes and prevent the spike in energy that occurs when you flip the switch on and heat the filament or gas inside the bulb.

The answer is…according to the MythBusters show: "Yes there is a spike when you flip the switch on but it is in no way significant enough to be considered money saving to leave your lights on for a few minutes while you leave the room. So it is best to turn off your lights even for a few minutes, than to leave them running fearing the spike in energy and a spike in your electricity bill. Also if you were to use energy saving bulbs in the bathroom and were constantly flicking them on and off you would have to replace them sooner and in the end you be paying more for the bulbs than your month's electric bill."

My thanks goes out to Mike Lawrence, for he knows the ways of the force.

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