Sunday, November 16, 2008

Random thinking on bulbs.

Our house has a lot of light bulbs. Lots of them. Most are recessed halogen floods. They burn out from time to time and they aren't cheap to replace. I hadn't relaced them with CFL's as they are of a particular form factor that is hard (short-necked 50w PAR30's, if you care).

Anyhow, fed up, I decided to bulk purchase them online. Price comparison:

Halogen at Home Depot: ~$9 each; 50w
Same online: ~$5 each; 50w
CFL equivalent online: ~$18 each; 15w draw
LED equivalent online: ~$25 each; 4w draw (but only equivalent to a 30W bulb brightness)

So if I wanted to replace them all (about 50 in the house), there's a $600 delta between CFL's and the regular halogens. On the other hand,at 9c per KW/hr, there's a savings of 16c/hr for every hour we have all the lights on, or maybe something like 5c/hr averaged over the course of a day, or $1.20/day. Call it $1 a day. So they pay for themselves in 2yrs or so.

Of course, they pay for themselves more quickly if used in high-usage lights, so that's where I'm going to start, having ordered less than a dozen of them. Will start with the kitchen and house entry and we'll see from there.

The LEDs should be an even bigger savings, but I'm a little worried the ones I found are too dim. Will look for some brighter ones and maybe try those out.

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