Don Klipstein wrote:

Average CFL has 3.5-4 milligrams of mercury. If you take your dead
ones to Home Depot or any recycling dropoff point recommended by
www.lamprecycle.org, most of it gets recovered.

I saw one cite saying 24% of CFLs are properly disposed of. It is an
EPA document giving numbers that I consider a bit optimistic for
amount of mercury in CFLs and how much mercury emissions from coal
they prevent:

http://www.epa.gov/waste/rcc/web-aca.../LindaBarr.pdf

That one does list other recycling resources.

Meanwhile, suppose as a less favorable example replaceing a 60 watt
incandescent with an 18 watt CFL that lasts 4500 hours. That saves
189 kilowatt-hours.

http://www.ecmag.com/index.cfm?fa=ar...rticleID=10261

cites an EPA figure of .012 milligram of mercury emitted into the
atmosphere by coal fired power plants per KWH of total USA electricity
usage. At this rate, that 189 KWH saved means 2.3 milligrams less
mercury pollution from coal-fired power plants - admittedly less than
is in an average CFL or even 76% of that (for 24% recycling rate),
but not by a whole lot.

Replacing 100 incandescents with CFLs should on average prevent
emission of more mercury than the CFLs contain, and with 75 watt ones
it is on average a close call. Replacing 60 watt incandescents
should reduce net mercury introduction to the environment if the
recycling rate improves from 24% or if national average life
expectancy improves to 5300-6000 hours (likely soon).


You make an excellent point about equivalence. That is, if we have already
accepted the amount of Mercury in the environment emitted from power plants,
then there is no need for hand-wringing, or even a discussion, about the
equivalent amount from CFLs.