This is a note from our Dean of Admissions at Lawrence, Steve Syverson.
We’ve been using CFLs for a couple of years and it seemed that some of
them needed to be replaced much more frequently than would be suggested
by the claims of lengthy life that are made on the packaging. (Just to
show you how neurotic I am — I even dated some of the bulbs we put in
to see how soon I needed to replace them). Found this research from the
Rocky Mountain Institute and I thought I’d share it with you.
The longevity of these bulbs is heavily affected by the length of time
they are “on.” If they stay on for about three hours each time you
switch them on, you will get the full longevity cited on their
packaging. On the other hand, if they are always on for just a shorter
period of time, it shortens their life as follows:
On for 5 minutes each time — they only last for 15% of their rated life.
On for 15 min each time — 30% of their rated life.
On for 1 hour each time — 80% of their rated life.
Regardless of the amount of time they are on, they still consume far
less energy than incandescent lights and generate less pollution (e.g.
even if they are on for only 5 minutes each time, it’s power use and
manufacturing produces only about 36% of the carbon dioxide emissions of
an incandescent bulb. However, in terms of your own cost savings, it is
a lot better to use them in places they will be on for an extended
period of time.
This does, however, suggest to me that we should consider using
incandescents in the Wilson House bathrooms because they are rarely on
for even five minutes (especially in the downstairs bathroom).
Additionally, as someone pointed out, using CFLs requires us to use a
little more heat because they don’t generate much heat, so maybe the
downstairs bathroom would also be a little warmer if we use
incandescents. 
One more important note — take all your “used” CFLs to Home Depot or
some other place that recycles them. A place close to campus is Kitz and Pfeil Each one contains a small amount of mercury. By properly recycling them, the
mercury is recaptured which is environmentally beneficial in two ways –
it keeps that mercury (a very toxic substance) out of the landfill, and
therefore out of the environment, and it avoids having the same amount
of mercury need to be mined and produced, thereby reducing further
destruction of land.
If you are geeky you can read more:
http://www6.homedepot.com/ecooptions/stage/pdf/cfl_recycle.pdf
http://www.rmi.org/
We’ve all got to get better and more informed about our consumption of
energy and products. If you discover meaningful environmental tidbits
that will help to inform us, please let us know.
