arkiemom asked in EnvironmentGreen Living · 1 decade ago

Energy saving or not? Does it really save energy to turn off light bulbs, TV's etc. when leaving a room?

I have heard the argument that turning lights etc. off and on actually uses more energy than just leaving them on if you are only going to be gone from the room for a few minutes. Is there any proof one way or the other? Or a "rule of thumb" to determine how long you should be gone before energy savings would be evident?

Also - what about frequently used computers? Which is more energy efficient - leaving them on stand-by or shutting down completely between uses?

8 Answers

  • 1 decade ago
    Favorite Answer

    First of all, turning things off really makes a difference. Just use a little common sense. For example, if you are walking out of a room for five minutes, don't bother. Like was indicated earlier, the difference minimal. If you are leaving a room for 15 minutes or more, then turn things off.

    Finding ways to reduce the use of appliances help has well. I like the post about reading rather than watching TV or surfing the web. If possible, trade books with friends when you see them or borrow them from the library. It may save you more on the electric bill but it will keep money in your pocket by not spending it on books. Between reading and exercising outside, I haven't turned on my TV in a couple weeks.

    I do use my home PC daily. However, I am only on long enough to answer necessary emails and when I am done with it, I shut down since it will use more energy during the hours it is idling than what it would use to boot it back up the next day. The link below is from Umbra Fisk of answering a similar PC-related question.

    Generally, a little common sense will go a long way. I set the heat/air conditioning back when I leave the house in the morning (everything in the house is electric), do only full loads of laundry (run the dryer as little as possible...about 75% of my laundry is dried on drying racks), take short showers (so the hot water heater works less), unplug small appliances when not in use (phantom usage...some pull power even when unplug it or turn off the power strip), etc.

    Not only will you use less energy, you will save money as well.

  • 1 decade ago

    with the exception of fluorescent lighting, it will almost always be a saving shutting things off (not on standby).

    an argument can be made for PCs in hibernation or standby where it may take a shorter time to resume work than reload everything.

    some machinery may take a time to warm up to working temperature and thus cost more to keep shutting down and restarting. An example is oil refineries where it takes 3 days to safely shut down all and another 3 days to get back to normal use. it will be more efficient and cheaper to run but at a min rate all the time. no doubt folks can supply many more examples of this sort of thing but the real answer is = overall shutting down GENERALLY will save energy.

  • 1 decade ago

    Yes, some devices take a spike of energy when they are first started up, but its milliseconds and over 10 minutes it averages out to a negligible difference.

    Unfortunately, many devices... set top boxes specifically, perform best if they are left on, or in standby.

    The best way to save energy is probably to be more frugal.

    Instead of watching tv or playing on your computer, buy a pile of second hand books and read them. Or go out for a very long walk.

  • 1 decade ago

    well if you are turning on a device and going to be using it then leave it on IE kitchen light you are making supper but doing other things while it is cooking do not turn the lights on and off as you check the meal leave it on but if you go into the basement for a beer and don't plan on going down the rest of the evening turn that light off,same things with the computer if you come home check e mails and want to play around on the computer or have set times for family members to go on-line better to leave the system on and turn off when all are done or bed time easier on the equipment to leave on instead of turning on and off every 5 minutes

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  • 1 decade ago

    With regular old-fashioned incandescent light bulbs (as well as LEDs) turning them off, even for a short period, is good.

    If your lighting is fluorescent....either regular "bar" fluorescents or CFLs....then it depends. If you're just leaving a room for 5 minutes and returning, then just leave them on. Those types of lights have a charger that ignites the gas inside to glow when you turn them on...and the charger uses more energy than just being on.

    (This is why I don't put CFLs in my closet light fixtures, since I never have them on for more than a minute.)

    For TVs, it's similar to fluorescent lights...they charge up. If you're leaving the room for less than ten minutes it really doesn't make sense to turn them off and back on again.

    For computers it's even more so...if you plan to use them again in like an hour, then standby is fine.

  • 1 decade ago

    Yes dear,it helps a lot in saving energy,with every drop combined,its become a POND,if every 1 saves little,it becomes a large saving of energy.when ur computer is not in use,u must shut down it,every unit saved is a gain 4 nation.

  • 1 decade ago

    you will save energy when you don't use it. It doesn't use extra energy to turn a light on because the electricity is waiting there doing nothing (and not being used)

    you should also unplug things when you're not using them because they use power even when not turned on.

    so turn off the lights to save money

  • pibe
    Lv 7
    1 decade ago

    To save energy. shut down everything you are not using, including your PC.

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