[RE-wrenches] CFL lighting and the mercury hazard.

[Joel Davidson]

Dan,

Thanks for reminding wrenches that LEDs are not more efficient than 
fluorescents. On the other hand, humans do not perceived light like sound so 
sometimes LEDs seem brighter (more lumens per watt) than other light 
sources. Our ears tell our brains fairly well if a sound is louder (more 
decibels), but our eyes do not accurately tell us if a light is brighter 
(lux or lumen). Like beauty, good lighting is often in the eyes of the 
beholder.

Question: where can I buy the most energy efficient DC Christmas lights?

Happy Holidays!
Joel Davidson

----- Original Message ----- 
From: "Dan Fink" <danbob at hughes.net>
To: "RE-wrenches" <re-wrenches at lists.re-wrenches.org>
Sent: Tuesday, December 09, 2008 1:43 PM
Subject: Re: [RE-wrenches] CFL lighting and the mercury hazard.


Woah, everyone. Slow down.

Snopes is indeed a great resource. However, they, like nearly every
media article cited, completely miss the point. Compact Fluorescent
bulbs contain no more mercury than do regular tube FLs, which have been
in use in homes and offices for decades. The disposal recommendations
are no different. Ask any office building custodian--the mercury warning
is printed on the base of most larger length T8s.

Proper disposal is needed for ANY broken FL or CFL--and has been for
decades.

As far as LEDs -- the reason LED lamps don't make much heat is because
they don't make much light, either. Lumen-per-watt figures for LEDs
still lag far behind FL or CFL. Yes, yes, there have been recent
announcements from LED companies -=- but take these all with a grain of
(metallic, heh heh) salt. Many of these figures take into account only
luminous efficiency, NOT real-world *total* efficiency. AND, the
high-efficiency ones are not generally available in room lighting
products yet -- they are available only as discrete LEDs.

LED lamps are extremely directional. They work fine for close-up task
lighting. But I have yet to see any LED lamp suitable for area lighting,
like a living room. I have installed and tried many, for myself (first)
and for customers. The usual response, after dark, when they see the
lighting of their living room, is --"You've got to be kidding me. I paid
$300 for THAT awful lighting?"

Give it a few years, and LEDs will be everywhere. But right now, they
are very marginal at best:
T8 FL = up to 95 lumens per watt
f40T12 FL = up to 65 lumens per watt
CFL = up to 60 lumens per watt
White LED = most ranging from 24 to 45 lumens per watt. Some have
reached 90 lumens per watt -- but are so far only available as discrete
components, not massed together in commercial lighting fixtures.
100w Incandescent = up to 17 lumens per watt

*Again, be VERY careful of LED lumen per watt claims. All the above
numbers are actual efficiency, not luminous. Most companies that
manufacture LED home fixtures do not measure light output correctly.
Contact me off-list if you want more info on how to actually measure
efficiency.*


REF:
http://en.wikipedia.org/wiki/Fluorescent_lamp
Don Klipstein:
http://members.misty.com/don/light.html
And almost every other page on his website.
Me:
http://otherpower.com/otherpower_lighting.html



DAN FINK
Technical Director, http://www.otherpower.com/
Co-Author, "Homebrew Wind Power"
ISBN 978-0-9819201-0-8



Phil Schneider wrote:
 > I agree – important to understand, and LEDs are a great alternative,
with cost being the significant factor.  This Snopes article mentions
the Maine DEP story:
 >
 > http://www.snopes.com/medical/toxins/cfl.asp
 >
 > The EPA factsheet at the end of the article has some “science”
regarding the quantity of mercury associated with a couple different
household items.  It also mentions how much mercury is released into the
air by a power plant (undefined) generating electricity.  This is an
interesting aspect I hadn’t considered before.
 >
 > P.
 >
 > *Phil Schneider*, system engineer
 > Creative Energies
_______________________________________________
List sponsored by Home Power magazine

List Address: RE-wrenches at lists.re-wrenches.org

Options & settings:
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org

List-Archive: 
http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org

List rules & etiquette:
www.re-wrenches.org/etiquette.htm

Check out participant bios:
www.members.re-wrenches.org