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Re: [Phys-l] CFL's not such a hot idea



Don,

Check the light temperature. You may need a 3000 deg lamp (Sylvania) if the glass globes are very absorbent. The lower temperature bulbs that are more common (2700 deg) tend to have a more yellow light.

Mark


-----Original Message-----
From: phys-l-bounces@carnot.physics.buffalo.edu on behalf of Polvani, Donald G.
Sent: Wed 5/16/2007 2:14 PM
To: Forum for Physics Educators
Subject: Re: [Phys-l] CFL's not such a hot idea

We are trying CFLs in our entrance foyer at home as replacements for 2
different lights (each with a single 60 w incandescent bulb). I've
forgotten the actual wattage of the CFLs (maybe 20 or 30 w), but they
are supposed to give the equivalent light output of a 75 w incandescent.
My wife and I both agree that the apparent light output is significantly
less with the CFLs than with the original 60 w incandescents. The bulbs
are fully enclosed in translucent glass globes. The CFLs give a
significantly more yellowish light than the original incandescents. I'm
wondering if the enclosing globes are preferentially absorbing the light
from the CFLs because they have a different spectrum than the
incandescents.

Has anyone else noticed an apparent decrease in light output when
replacing an incandescent with a CFL with a reputed equivalent or
greater light output? If so, were the bulbs enclosed by glass globes?
The decrease in light output is so noticeable that we are considering
replacing the CFLs with the original incandescents.

Don Polvani
Northrop Grumman Corp.
Undersea Systems
Annapolis, MD

-----Original Message-----
From: phys-l-bounces@carnot.physics.buffalo.edu
[mailto:phys-l-bounces@carnot.physics.buffalo.edu] On Behalf Of Crawford
J Maccallum
Sent: Wednesday, May 16, 2007 4:01 PM
To: Forum for Physics Educators
Subject: Re: [Phys-l] CFL's not such a hot idea

We have to remember that the tradeoff is between 4 mg mercury in the
landfill for a CFL vs a much larger amount put into the _air_ by a coal
fired power plant providing the extra energy for an incandescent.

At least that's what I read.

Crawford MacCallum
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_______________________________________________
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