Tuesday, December 23, 2008

Are fluorescent bulbs really more energy efficient than incandescent bulbs?

Well, of course they are …

Compact Fluorescent Light Bulbs : ENERGY STAR

  • ENERGY STAR qualified bulbs use about 75 percent less energy than standard incandescent bulbs
  • …Produce about 75 percent less heat…
  • Or are they?

    It’s been a cold December in Lake Wobegon. The heat is on all the time.

    Our incandescent bulbs are 100% efficient now. They give light and heat, and we need both. Our fluorescents are equally efficient of course, they also give light and a bit of heat. We need that heat too.

    True, we don’t need heat all year long. There are a few weeks during the summer when we run air conditioners, though not usually when the lights are on. For several months the heat is indeed a waste.

    So fluorescents are more energy efficient than incandescents – on average. In Minnesota though, that’s only true on average, and the benefit is much less than 75%. Maybe 25%.

    So maybe they only save us $10 in electricity costs over their lifetime, versus $30 in Florida. That means we don’t get much of a payback from switching, and given the hassles of dealing with broken fluorescents they’re probably not worthwhile for Minnesotans.

    Of course we’ll have to switch in 2012 with the rest of the nation, but there’s no reason to jump the gun …

    1 comment:

    cathy said...

    I have cfl's for lights that I have on a lot and ones where excess heat bothers me in the summer, but I'm not crazy about bringing more hazardous waste into the house. I hope led's get better and cheaper by 2012.