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Golly, I hate being the one to say this....RE: P2 Impact of Bulbs... but I guess I'm feeling curmudgeonly today

Rodney - I really liked learning of the references you mentioned for what they do well. But there are two things these references did not do well -

1)  The EPA Power Profiler http://www.epa.gov/cleanenergy/powerprofiler.htm incorrectly identified my power company.  One of the limitations of using a zip code to ID power companies is that more than one power company may serve a single zip code. But it serves as a very good first approximation - and one I did not previously know about... so thanks again

2)  The second part of what it does not do is identify mercury impact of  power plants.  It would be helpful to the "P2 impact of CFL" discussion, but I did not see it there.  As it is, with only the  other emission information provided, I suppose that could imply that these other pollutants pose a greater environmental health risk that does Hg - which may be true due to any number of reasons.  

Rant about mercury in CFLs:
That second bit  - about mercury and CFLs - is becoming a frequent question that we really ought to be able to answer. Every time I attend a meeting where someone suggests that CFLs are preferable to incandescents (which I accept), some bright, mercury-minded person points out that CFLs have mercury in them, too, and asks the obvious - how is it that putting Hg-containing devices into the home in a place where one did not exist already is a net benefit to the environment?  IMHO, no-one has adequately answered this, and to make the point, I jotted down a quick calculation to highlight where the assumptions exist (see below) - asking anyone who is making the claim about a positive benefit to pony up the evidence to support their claim.  Otherwise, we leave the technical folks in the field in the nasty position of appearing to distribute another urban legend - something that sounds good, but maybe isn't. So I put it to anyone on the listserve - I'm from Missouri, so I've got the birthright to say this:  SHOW ME the data!  I'll warn you up front that there are several variables, and in my mind the correct reply would likely be a multi-variable graph like a fan curve or a pump curve or a psychrometric chart - different size CFLs have different amounts of mercury (I don't believe this is a straight-line curve) and replace different wattages of incandescents (again, I don't think it is a straight line relationship for energy saved, from which one learns the power demand from the power plant).  Additionally, the "mercury used" comparison between bulb (relatively static for a specific wattage of CFL bulb) and emissions from the power plant (potentially widely variable, depending on the source of the coal used to power the plant) is dynamic at best.

I'm getting a little tired of useless comparisons (what does a comparison of the amount of mercury in a bulb compared to the amount of Hg in a watch battery tell me?), worthless reference links to website home pages (not publications found in deep links - you know, with page numbers and specific quotes, like you had to do to get a passing grade in school?) and generally unsubstantiated claims.  The people I talk to deserve to be given good information.  

What follows is an earlier request I made for information on the subject - weigh in, please, if you have an answer.  

The EPA Energy Star fact sheet, Frequently Asked Questions Information on Proper Disposal of Compact Fluorescent Light Bulbs (CFLs), was referenced in our meeting (thanks to Fred in our office for finding the URL for me) ....


You will need to read a bit, and it never really answers straight out the question, "if a CFL has mercury, then doesn't that reduce its benefit relative to an incandescent, which has no mercury?"  

The answer?  "Nope, a CFL is still clearly better than an incandescent."

Here's why:

In the fact sheet it is noted that a CFL uses about 1/4 the energy of an incandescent - 13W v. 60W.  In fact, this multiplier slides around a bit, becoming more favorable to the CFL than  to the incandescent as the light power (lumens) increase.  Check out the chart here:


This means that (for lighting powered by coal-fired power plants) the amount of energy used at the plant to power the incandescent bulb is ~4x that of powering a CFL for the same lumens.  Therefore, the Hg emissions at the plant are ~4x, too.  So, the question is, how much Hg is emitted per watt generated?  According to the EPA fact sheet referenced above, "A coal-fired power plant will emit 13.6 milligrams of mercury to produce electricity required to use an incandescent light bulb, compared to 3.3 milligrams for a CFL."  Unfortunately, the fact sheet fails to tell us the size of the bulb associated with these rates, i.e., what the emission to wattage ratio is for these bulbs.  So, I am assuming they are still referring to the 60W and 13W bulbs mentioned earlier in the sheet.  Also, having just reviewed an article that clearly demonstrates a viable mercury reduction strategy for coal fired power plants exists by carefully testing and preferentially purchasing low mercury content coal - different sources have markedly different content - I'm skeptical that these are precise numbers of mercury emissions.  Mercury emissions will vary widely, depending on the coal seam used and on control technology - EPA Energy Star should address this.

In order to answer the question, "Is the amount of mercury in a CFL + the amount of mercury emissions associated with the energy required to power the CFL less than the amount of mercury emissions associated with the coal fired power used to light an incandescent bulb?" we need to know how much mercury is in a CFL bulb. Again, from the fact sheet we can't tell what size bulb EPA is talking about, and the amount changes depending on size, but let's again assume the 13W bulb.  The fact sheet says the average is 5mg of mercury in the bulb.  A chart with 2002 and 2003 mercury amounts associated with different bulbs available under a New Jersey contract is available here:


There is also a comparison of the CFL amount of mercury compared to other household devices in the fact sheet, and here's a chart that compares amounts in other items, too.


But I'm not sure that's a worthwhile comparison - after all, aren't we trying to get rid of as much mercury as we can?  Those comparable items will be harder to find as we continue to have success in our mercury reduction efforts.  But back to the calculations...

For a 60W & 13 W comparison, the energy used is:

60W = (13.6 milligrams of Hg from the coal fired power plant + 0 in the bulb) = 13.6 mg

13W CFL = (3.3 milligrams of Hg from the coal fired power plant + 5 in the bulb) = 8.3 mg

Therefore, a net reduction of Hg for CFL, not to mention less pressure on the power plant to generate more greenhouse gases.  A nice image to illustrate the difference between the bulbs can be found here


and here


and supposedly in a 2002 EPA document, unspecified.  As you can see, the numbers are different in this image, which only serves to add to the confusion.  Why can't EPA Energy Star adequately reference their assumptions???

I want to add this comment:  if properly handled, the mercury in a CFL will be managed (the likely worst case is that it will go to a landfill), while the mercury emitted from a power plant is disposed in an uncontrollable fashion.  And we all know that the waste management hierarchy tells us the CFL management (hopefully captured and recycled) is preferable to that of emission from  the power plant.

And of course, CFLs won't be the sensible choice (from a potential Hg exposure risk) if you can afford to power your home with sufficient renewable energy...  But that's not who we were asking for, was it?

OK - that's the end of the rant - let me know of the information you have -

Richard Yoder, PE
Director, P2ric.org
University of Nebraska at Omaha
6001 Dodge Street, RH308
Omaha, NE 68182
vox: 402-554-6257
fax: 402-554-6260


P2RIC, the Pollution Prevention
Regional Information Center, is
a proud member of the Pollution Prevention
Resource Exchange, P2Rx.org.

"Sobin,Rodney" <rsobin@deq.virginia.gov>
Sent by: owner-p2tech@great-lakes.net

12/13/2006 12:43 PM

Please respond to
"Sobin,Rodney" <rsobin@deq.virginia.gov>

"Sue Schauls" <sue.schauls@uni.edu>, "P2 providers in Region 7" <p2r7@p2ric.org>, "P2 Tech Listserve" <p2tech@great-lakes.net>
RE: P2 Impact of Bulbs

Sue and other fellow P2Techers,
Thanks for relaying the P2 and lighting information.
For those of you interested in determining emissions avoided from electricity savings (whether from efficient lighting or other end use measures) and alternate supply( renewable generation and CHP/co-gen), there are some other tools and data available.
EPA Power Profiler http://www.epa.gov/cleanenergy/powerprofiler.htm provides average NOx, SO2, and CO2 emissions per MWh on a regional basis.
EPA eGRID http://www.epa.gov/cleanenergy/egrid/index.htm “eGRID is a database that provides information on the air quality attributes of almost all the electric power generated in the United States. eGRID provides you with many search options, including information for individual power plants, generating companies, states, and regions of the power grid.”
DOE Energy Information Administration http://www.eia.doe.gov/cneaf/electricity/st_profiles/e_profiles_sum.html provides state summary reports, which include NOx, SO2, and CO2 emissions from electricity generation. (Click on state name for state summary report.)
Please be aware that your local and regional generation mix and, thus, emissions per MWh vary based on demand, generation asset availability, and other factors affecting utility power dispatch.
Rodney Sobin
Office of Small Business Assistance
Virginia Department of Environmental Quality

NOTE NEW--Postal: P.O. Box 1105, Richmond, VA 23218-1105

Street:  629 E. Main St., Richmond, VA 23219-2429
Tel. 804-698-4382       fax 804-698-4264


Environmental Assistance for Small Businesses http://www.deq.virginia.gov/osba/smallbiz.html
Virginia Comprehensive Assistance Network http://www.deq.state.va.us/osba/vacan/
DEQ Innovative Technology http://www.deq.virginia.gov/innovtech
DEQ Distributed Energy Resources http://www.deq.virginia.gov/innovtech/der1.html
-----Original Message-----
owner-p2tech@great-lakes.net [mailto:owner-p2tech@great-lakes.net] On Behalf Of Sue Schauls
Wednesday, December 13, 2006 12:41 PM
P2 providers in Region 7; P2 Tech Listserve
P2 Impact of Bulbs

Apology for cross posting and please forward to appropriate regional P2 listserves.
The Small Business Pollution Prevention Center has recently posted the Impact of Pollution Prevention tools at http://www.iwrc.org/SBPPC/index.htm
I hope that the data presented in this project is useful to your clients and in assisting with more meaningful measurements as to the actual impact of P2 by quantifying the toxins reduced when P2 suggestions are implemented.

Pollution Prevention Impact of Fluorescent Bulbs

Incandescent bulbs and fluorescent tubes are the most common lighting used in businesses today. Switching to either compact fluorescent or low-mercury fluorescent bulbs can have a major impact on energy cost savings, as well as lessen your contribution to energy production-related pollution, including global warming.

Fact Sheets
·         Light Bulb Facts (pdf format)
·         Compact Fluorescent Bulbs (pdf format)
·         Interactive Compact Fluorescent Bulb cost worksheet in MS Excel format
·         Low-mercury bulbs (pdf format)
·         Interactive Low-mercury bulb cost worksheet in MS Excel format
·         Universal Waste Rule (MS Word format)
·         Fluorescent Bulb Recyclers (MS Word format)
·         Emission Factors for Coal-fired Power Plants
Sue Schauls
Program Manager

Iowa Waste Reduction Center
1005 Technology Parkway
Cedar Falls, Iowa 50613
319/273-8905 or 1-800-422-3109
Fax: 319/268-3733