Friday, November 14, 2014

All incandescent bulbs must be destroyed

If you saw an investment opportunity where you were guaranteed 100% return per year, would you take it?  Incandescent bulbs (you know, the regular cheap kind) cost far more in electricity usage than the sticker price at the store. If you have them plugged in anywhere in your home, they are unnecessarily costing you more.  If the sticker price at the store included the cost for the electricity they will consume over their lifetimes, no one would buy them.

So now for the investment pitch: replace all lighting in your home with LED lighting, and throw away the incandescent bulbs so nobody plugs them in by accident.  The LED bulbs are at least 6 times more efficient, and will pay for themselves in savings in as little as 8 months.

(read in Jim Gaffigan  audience voice)  Throw away the incandescents? That's so wasteful!
 Nope. Plugging them in and having them waste energy ever again is way more wasteful. Send em to the landfill.

The bulbs will pay for themselves in savings - it's just a matter of time.  to calculate the savings from a bulb purchase, you will need to know:

  • C = Your electricity cost.  There is a standard rate on the bill, but don't forget to add in any taxes or per kwh fees. Mine works out to $0.14 after all taxes and fees.
  • H = How many hours per day the replaced bulb is used. for this example let;'s say 4 hours per day.
  • W = the old incandescent bulb wattage (usually 60)
  • N = the new wattage for the LED bulb (usually 9.5 for a 60W replacement)
The savings per month are (H*W - H*N)/1000 * C * 30 

So in our example, the monthly savings will be around $0.85 per month.  If I got the bulb for $5 (yes, $5, at Ikea), the payoff period will be under 6 months.  Every 6 months a little green leprechaun hands me $5.  And all I had to do was replace a light bulb.  Oh, and did I mention that these new bulbs will last 20 years?

Now that you are sold on this investment, you have the task of selecting the brand and type of bulb. Here are the standard ratings that differentiate what type of light the bulb you are getting:


  • Brightness: All bulbs are measured in lumens. A 60W bulb from the dark ages puts out around 800 lumens. Anything from 700 to 900 will look similar in brightness.
  • Color:  The color of the light (or yellowness) is measured as a temperature, corresponding to the blackbody radiation spectra of a material heated to that temperature measured in Kelvin, or K for short.  Soft white is the most common at 2700K.  Bright white will be some higher number.
  • Color Rendering Index: This is the accuracy of the bulbs attempt to replicate an incandescent bulb. A score of 100 would be perfect and no one could tell the difference. Some brands advertise this number, which is a good sign that they have done some engineering to get the bulb to put off good light.
  • Dimmable: If you have a dimmer switch, make sure it says "dimmable" without the "not" in front of it somewhere on the package.
  • Enclosed fixtures: If you are installing in a closed fixture, be sure that the packaging is marked as being rated for enclosed fixtures.  The reason some bulbs will not work in enclosed fixtures is due to the heat being dissipated from the bulb. Although this is much less heat than an incandescent, it is enough to damage the bulb if it builds up in the fixture.
Here are a few bulbs that I have purchased and tested, and have found to have acceptable light color and brightness:
  • IKEA - yes, IKEA has 700 lumen LED bulbs at $4.50.  Some have a transparent case and look nice in exposed fixtures.  They have a few different styles to choose from.  Good light color and are dimmable too.
  • Phillips - In my opinion the best brand for bulbs, but not cheap.  I have Phillips for all my overhead recessed lighting.  $12 to $20 each.  Home depot stores in minnesota have some bulbs at reduced prices, thanks to subsidies from XCEL energy.
  • Feit - $6 - $12 each - Costco had a deal on these last month.  Feit bulbs were among the best rated on consumer reports.
While typing this I have completely forgotten to mention the real reason I am typing this blog, which is the fact that with each incandescent bulb that gets replaced by something more efficient, the ice caps will melt at least a little less fast.  But even if you don't believe "science", there's no denying your wallet.