Today, I noticed a bookcase light that we often keep on all night long. I noticed it because I turned it off - rather than another family member.
As I looked at it, I realized it's a smaller 50 watt flood r-20, but not the larger br-20 that can be found in a can light in the ceiling.
Flourescents cost about $7 at Menard's. I'll try to pick one up today.
It's amazing how many lights we have in our house, appliances and even furniture.
I wonder if a multi-day audit isn't worth doing.
With the cost of compact flourescents in transition - many dimmable or less commonly shaped bulbs are still expensive - I wonder if replacement is best done by prioritizing usage; i.e. what stays on longest should be changed.
The question is, who has time to audit their light bulb usage?
My thinking is that any bulb that's noticeably used for more than 3 hours a day - or as a night or safety light - is probably a good candidate for immedaite replacement.
Other candidates may be out of the way bulbs that are difficult to reach - they can be replaced opportunisticly when service people are available.
I've talked with friends and read articles about people who gradually replace incandescents with CFs as their bulbs burn out. I imagine this will lead to most bulbs being replaced within 2 years, however, it doesn't seem to have the immediate economic (and environmental) benefit of immediately replacing the high usage bulbs.
One category of lights we haven't replaced are our outside lights. While I've hesitated due to the importance of immediate light (sometimes we can't wait 30 seconds for the bulb to reach peak illumination), I wonder how often we use these lights due to timers.