Since this seems to be a fairly hot topic here I thought I'd give it
another little shove. (And I hope Don Klipstein responds, as he seems to
be one of the most knowledgeable folks here in this field.)

So it's one of the burning questions of our age: are CFLs really that
much more efficient than incandescents? Should we go whole-hog over to
what Homer Simpson calls the "twirly" light bulbs to save ourselves (by
cutting carbon emissions, etc.)?

Plus now we have a new contender, LEDs, to throw into the mix.

If I were Ayatollah of the world, here's what I think I'd do. I would
want good answers to all these questions, based on good science and not
just speculation, "common sense" or other less reliable ways of arriving
at a conclusion.

I would order a Grand Study of the problem. This study would not just
look at the efficiencies of various bulb types in isolation: it would
attempt a holistic approach, where every aspect of creating and using
light bulbs is considered, not just the simple matter of CFLs using less
electricity to emit the equivalent amount of light:

Seems to me there are the following aspects to consider:

1. Production costs:
o Energy consumed by producing each type of bulb
o Materials required by each type, and energy consumed by obtaining them
o Environmental consequences of producing each type
o Monetary cost to consumer of each type

2. Usage costs:
o Comparative energy consumption of each type per unit of light
o Comparative heat produced by each type
o Longevity of each type
o Comparative cost of each type, based on energy consumption and lifespan

3. Disposal costs:
o Actual physical disposal (recycling, landfilling) costs
o Environmental consequences of disposing of each type

I think these "top-level" categories should cover most of the important
questions that should be answered in order to set light-bulb usage policies.

One of the most important things to consider, I think, is the fact that
CFLs contain fairly complex electronics, requiring construction at the
front end and disposal at the back end. How much energy does this all
consume? (That little matter of mercury in CFLs also demands investigation.)

It's important to look at something like this holistically so that we
don't end up embracing a policy that, to use an analogy, yields a barrel
of oil while requiring two barrels of oil to produce it.

================================================== ==========

Side note on LEDs: I ran across an article someone had posted a link to
in another newsgroup that's interesting, talking about how LEDs aren't
ready for "prime time" as lighting devices because of a potential energy
inefficiency due to the phenomenon known as "droop":

http://www.spectrum.ieee.org/semicon...ds-dark-secret


--
Found--the gene that causes belief in genetic determinism