Z.Monkey’s Blog

So we went to the Home Depot last night to pick up some supplies. One of our main goals for was to replace a bunch of the lighting in our home with Compact Fluorescent Light (CFL) Bulbs. Our new condo has several recessed lighting fixtures all of which were loaded with 100W Halogen Bulbs; these we replaced with 13W CFL. So if the current rate for power from PSNH is 7.34 cents/kilowatt-hour and if the average life of a CFL is 8000hrs (6 years) then…

(100W * 8000hrs) * ($.0734/1000WHrs) = $58.72

(13W * 8000hrs) * ($.0734/1000WHrs) = $7.63

Those numbers are cost over 8000 hours (which they say is 6 years of use) and since we replaced 6 of the 100W halogen bulbs we will save $51.09 dollars per year in energy costs. Of course we had to pay for the new bulbs. These were $7.99 for a 4 pack* (plus a $1 dollar instant coupon from PSNH) which makes for $1.75 a bulb. So $51.09 - (6 * $1.75) is $40.59 our first year!

Incandescent, Halogen and Compact Fluorescent Light Bulbs

In case you are wondering these numbers are ridiculously inflated. I doubt that we’ll have each of these lights on for 1300 hours per year, but in any case they say that it only takes 500 hours of use to pay off a CFL and after that it is pure savings! Of course, there are other benefits to using less energy than just saving money but after you buy something as expensive as a condo you want to pinch pennies as much as possible (especially if those pennies can go towards video games, beer, or TV.) I’m not going to talk about whether the manufacturing process for CFL are better than normal light bulbs because I honestly don’t know but it would be interesting to find out.

Oh, and we also replaced 4 60W bulbs in our upstairs bathroom for an extra $18.40 in savings.

*We bought a different brand of bulbs from Home Depot.