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

[Ian Woofenden]

Great stuff, Dan.

I'll add some info from a short piece we ran in HP120:

"An average-sized CFL bulb contains approximately 4 milligrams (mg) 
of mercury, an amount about equal in size to the period at the end of 
this sentence. Standard 4-foot-long T12 fluorescent tubes contain up 
to 21 mg of mercury and modern T8 tubes with electronic ballasts can 
contain about 10 mg per tube. By comparison, watch batteries contain 
as much as 25 mg-the equivalent of about six CFLs. Older home 
thermostats contain from 500 mg to 2 grams of mercury, or the amount 
in 125 to 400 CFLs."

"The greatest source of mercury in our environment comes from burning 
coal, the most common fuel used in the United States to generate 
electricity. A CFL uses 75 percent less energy than an incandescent 
lightbulb and lasts at least six times longer, so the mercury 
emissions that result from the coal-fired electricity used to power 
it are considerably lower. If you're relying on coal-fired 
electricity, over a bulb's lighting lifetime, using a CFL produces an 
additional 2.4 mg of mercury emissions. Contrast this with the 10 mg 
of emissions produced by using a conventional incandescent bulb over 
the same five-year life span. Incandescents produce more mercury 
contamination than CFLs, and this is only gaseous emissions from a 
typical coal-fired power plant. You also need to consider the mercury 
leachate from coal mine waste and fly ash disposal. More coal needed 
for electricity translates into more coal mined-resulting in more 
mercury pollution."


All animals have impact. Let's reduce ours, sensibly.

Best,

Ian

At 2:43 PM -0700 12/9/08, Dan Fink wrote:
>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
>_

-- 
Ian Woofenden <ian.woofenden at homepower.com>, Senior Editor, Home Power magazine
Subscriptions: $24.95 per year PO Box 520, Ashland, OR 97520 USA 
800-707-6585 (US), 541-512-0220
or download free sample issue at <http://www.homepower.com>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20081209/c5fdc3b9/attachment-0003.html>