The other night I was flipping through the channels (on my energy efficient TV) and stumbled on one of my favorite shows, Mythbusters.
Mythbusters is one of those shows I stop on, watch, flip during the commercials, but always come back to see if the myths being testing are BUSTED, PLAUSIBLE, or CONFIRMED.
The episode that was on was called “22,000-Foot Fall”, which originally aired in December 2006. In this episode, they were testing multiple myths, but one that caught my attention was a popular energy conservation myth:
Myth: Leaving a light on will save electricity.
The Mythbusters crew, led by Jamie, tests this popular myth. The myth followers believe it takes more energy to turn the bulb back on each time you turn it on, and the surge is so great, that you should keep the light on - all of the time.
Jamie and his team created an inductive current loop, which captures and measures how much current is going through the wires to turn the light bulb on (the surge), and how much energy it consumes while turned on.
They had a inductive current loop set up and generated the tests of a 90W incandescent bulb, a 10W CFL, a 70W halogen bulb, and a 1W LED bulb.
Furthermore, they brought up the concern about turning the light on and off will shorten the life of the bulb. What’d they do? They set up a system that turned each light on and off every 2 minutes for 6 weeks straight! That’s a lot of on and offs!
So, what’s the verdict? Is it more effective to keep the lights on, or to turn them off? Will it wear the bulb out?
According to Wikipedia, “The MythBusters calculated that the power surge from turning on a light would only consume as much power as leaving it on for a fraction of a second (except for fluorescent tube lights; the startup consumed about 23 seconds' worth of power). Furthermore, the wear and tear of turning the light on and off repeatedly did not reduce the bulb's total life expectancy enough to offset the increased electricity usage. Therefore, it is far more economical to turn a light off rather than leaving it on.”