Electricity Question

I once heard that it uses less electricity to leave a light on for several minutes vs. turning it off and on in between uses.

The theory suggested that it takes more energy to turn the light on (getting the current running) than it takes to leave it on for a short period of time.

There must be a threshold of minutes off outweighing the energy that it takes to turn the light on.

I do not support this theory either way because electricity is not my field. However, I would like to know because I find myself constantly going in and out of rooms, turing the lights on and off as I do.

[Ima saver]

I would like to know also. Any experts??

[infocus]

I remember being told by my first boss many years ago that this applied to flourescent lights used to light conference rooms, and that the 'breakeven point' was 20 minutes. I don't know if that is true, and I don't know if that applies to lighting in most homes. I have read that there are certain types of light bulbs we can use that will save energy, but I can't remember which ones...

[PrincessPerky]

I started a thread on that myself. I found that flouresant lights are the ones that have a startup surge. but I never nailed down a time for leaving it on vs turning it off.

[nixuzer]

Originally Posted by Sticking It to the Man

I once heard that it uses less electricity to leave a light on for several minutes vs. turning it off and on in between uses.

The theory suggested that it takes more energy to turn the light on (getting the current running) than it takes to leave it on for a short period of time.

There must be a threshold of minutes off outweighing the energy that it takes to turn the light on.

I do not support this theory either way because electricity is not my field. However, I would like to know because I find myself constantly going in and out of rooms, turing the lights on and off as I do.

Purchasing one of these will pay for itself in the first year if you have any sort of electrical usage. It doesn't answer your question about the lightbulb however it does address the point of saving electricity. However to address the lightbulb question found this on a google group thread (see below for a snippet).

A compact fluorescent loses about 6 minutes of lifetime (0.001% of its
10,000 hours) every time you turn it on, so you might leave it on for a
few seconds when leaving a room, to save 0.01 cents of a $10 bulb cost,
while consuming 10W/1,000/60x10 = 0.0016666... cents per minute's worth
of energy at 10 cents/kWh. Frugal people might turn it off if they were
going to be out of a room for more than 6 minutes, at which point the
energy saved is worth more than the increased bulb lifetime...

[Fern]

Ask your electric company.

[fultron]

Googled the question and 'Mr Electricity' says turn off the light to save power...

http://michaelbluejay.com/electricity/myths.html

[Ima saver]

Thanks fultron, now we all know. Turn it off!!

[flash]

Fluorscent bulbs are a different category. Regular bulbs have a tiny extra surge when you turn them on, so slight difference in $, but the bigger difference is the wear on the bulb. Establishing the connection wears them out faster (ever notice how often they blow when turning on the light versus just being on?).

The new halogen bulbs have a lifetime of 5 years compared to a regular one year bulb. There is a thread on this somewhere. Anyway, they have a warm up period, so it takes a moment for the light to reach full brightness, but they use less energy and wear out much less frequently.

Thanks. Mr. Electricity is the man I suppose.

I read much of his site, but I refuse to take his advice and open my heating vents in rooms I don't use.

I've been doing that for years without problems.

[Ima saver]

I am sure there is a reason for that. wonder what it is?

Mr. Electricity said it can overwork your furnace leading it to malfunction, from pushback pressure from the closed vents.