Thanks for your informative “rant.”
The discussion and calculations are good and I agree with your conclusions.
As to the critique of the power plant
emissions data not including Hg, you’re right. NOx and SO2 data have been
collected for some time due to their criteria pollutant status and contributions
to acid rain; CO2 data collected because of climate change contributions. Of
course particulate matter (PM) and CO are also regulated power plant pollutants.
And not only do coal-fired power plants emit Hg but they also emit other heavy
metals—arsenic, beryllium, cadmium, chromium, lead, nickel, uranium,
thorium, potassium-40, among others—that may be of concern. (Google can get
to some of the literature, such as http://www.awma.org/journal/pdfs/1998/2/biswas.pdf
and on the radionuclides http://www.ornl.gov/info/ornlreview/rev26-34/text/colmain.html
With regard to the lamps, maybe someone
else on the list knows, but are the CFL manufacturers making the effort to
reduce Hg in CFLs as they have with fluorescent tubes? With the fluorescent
tubes, there are brands that have reduced Hg content (some have green or gold
end-caps) and there are some that claim EPA TCLP compliance. These aren’t
the same thing. Some of the TCLP-compliant tubes contain additives to better
absorb or adsorb Hg to meet TCLP. So a green-capped tube may have less Hg
than other tubes but may or may not be TCLP compliant. And a tube may be
TCLP compliant and not necessarily have less Hg than non-TCLP-compliant tubes.
Again, I don’t know if this stuff is going on with the CFLs too.
From: Rick Yoder
December 13, 2006 5:04 PM
Cc: P2 Tech
Listserve; Sue Schauls; p2r7;
Subject: Golly, I hate being the
one to say this....RE: P2 Impact of Bulbs... but I guess I'm feeling
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 -
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
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.
about mercury in CFLs:
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.
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.
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
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) =
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 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
University of Nebraska at Omaha
6001 Dodge Street, RH308
Omaha, NE 68182
the Pollution Prevention
Regional Information Center, is
a proud member of the Pollution Prevention
Resource Exchange, P2Rx.org.
12/13/2006 12:43 PM
<firstname.lastname@example.org>, "P2 providers in Region 7" <email@example.com>,
"P2 Tech Listserve" <firstname.lastname@example.org>
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
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
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
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.
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
Assistance for Small Businesses http://www.deq.virginia.gov/osba/smallbiz.html
Virginia Comprehensive Assistance
DEQ Innovative Technology http://www.deq.virginia.gov/innovtech
Energy Resources http://www.deq.virginia.gov/innovtech/der1.html
Behalf Of Sue Schauls
Sent: Wednesday, December 13, 2006 12:41 PM
To: P2 providers in Region 7; P2 Tech Listserve
Subject: P2 Impact of Bulbs
for cross posting and please forward to appropriate regional P2 listserves.
Small Business Pollution Prevention Center has recently posted the Impact of
Pollution Prevention tools at http://www.iwrc.org/SBPPC/index.htm
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
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.
· Light Bulb Facts
Fluorescent Bulbs (pdf format)
Fluorescent Bulb cost worksheet in MS Excel format
bulbs (pdf format)
Low-mercury bulb cost worksheet in MS Excel format
Waste Rule (MS Word format)
Bulb Recyclers (MS Word format)
Factors for Coal-fired Power Plants
Waste Reduction Center
1005 Technology Parkway
Cedar Falls, Iowa 50613
319/273-8905 or 1-800-422-3109