United States
Environmental Protection
Agency
Air and Energy Engineering
Research Laboratory
Research Triangle Park, NC 27711
Research and Development
EPA/600/S7-91/005 Nov 1991
EPA Project Summary
Field Performance of
Woodburning and Coalburning
Appliances in Crested Butte
During the 1989-1990 Heating
Season
Dennis R. Jaasma, Mark R. Champion, and Mahesh Gundappa
The field performance of woodburning
and coalburning appliances in and
around Crested Butte, CO, has been
evaluated. Measurements included par-
ticulate matter (PM), carbon monoxide
(CO), and weekly average burn rates.
Woodburning appliances included con-
ventional airtight stoves, EPA-certified
catalytic stoves, and EPA-certified
noncatalytic stoves. Compared to the
emissions measured from conventional
stoves, the certified stoves reduced PM
emission factors (grams/kilogram) by
53% and CO emission factors by 49%.
Coalburning appliances included a com-
mercial scale boiler, a residential stoker,
and a hand-fired coalstove. The coalburn-
ing appliances were compared to con-
ventional woodstoves on a grams of pol-
lutant per joule of heat output basis. The
automatically stoked coal appliances re-
duced PM and CO emissions by roughly
84 and 85%, respectively. The hand-fired
stove was cleaner than expected, reduc-
ing PM by 55% and CO by 27%.
This Project Summary was developed
by ERA'S Air and Energy Engineering
Research Laboratory, Research Tri-
angle Park, NC, to announce key find-
ings of the research project that is fully
documented in a separate report of the
same title (see Project Report ordering
information at back).
Introduction
The Town of Crested Butte (Colorado)
contracted with Virginia Polytechnic Insti-
tute (VPI) for the field measurement of
woodstove emissions in Crested Butte dur-
ing the winters of 1988-89 and 1989-90.
These measurements were intended to
determine the effect of a town-wide
changeover from conventional to EPA-cer-
tified woodstoves. Both paniculate matter
(PM) and carbon monoxide (CO) emis-
sions were to be measured. The hard-
ware used for the measurements is known
as the "VPI sampler." This sampler has
been compared to the EPA reference
method for PM (EPA Method 5G) and has
been found to be accurate.
This report deals primarily with the re-
sults of the second year of work, wherein
emphasis was on measurement of emis-
sions from the certified stoves which cur-
rently make up over 90% of the stove
population in Crested Butte. However, in
order to gain some additional data on old
technology stoves, 17 weeks of conven-
tional stove monitoring was performed in
houses outside the town limits. To get
preliminary information on how coalburning
sources affect the Crested Butte airshed,
13 runs were performed on three coal-
burning sources.
The project was overseen by an advi-
sory committee composed of representa-
tives of the Town of Crested Butte, Colo-
rado Department of Health, EPA, and the
Wood Heating Alliance (WHA). Major
project decisions such as the number and
types of appliances to be sampled were
handled by the advisory committee. Addi-
tional technical guidance was provided by
the EPA Office of Research and Develop-
ment.
Prior to the winter of 1989-90, many
certified stoves in Crested Butte were ex-
amined by representatives of WHA. Fresh
catalysts were installed in most of the
Printed on Recycled Paper
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older catalytic stoves. All chimney sys-
tems were checked to determine their ad-
equacy. During the project, the results of
the sampling were reviewed weekly by
WHA. If a stove was performing at emis-
sion levels greater than expected, the op-
erator was contacted in an attempt to de-
termine if the stove was being used prop-
erly. Remedial steps (e.g., catalyst replace-
ment, further operator training, stove re-
pair, or stove replacement) were taken in
some instances.
A field laboratory was set up in space
provided by the Town of Crested Butte,
and sampling commenced on October 30,
1989. Sampling continued until April 9,
1990. The appliances in 27 houses were
monitored: 7 conventional stoves, 12 cata-
lytic stoves, 5 noncatalytic stoves, and 3
coalburning appliances. One- catalytic -
model (two nouses) and two noncatalytic
models (two houses each) were EPA
Phase II certified. The remaining catalytic
and noncatalytic models were EPA Phase
I certified. All catalytic and noncatalytic
stoves were Colorado Phase II certified.
This report describes the results of the
1989-1990 sampling and compares the
results with data from 1988-1989.
Summary and Conclusions
During the 1988-89 and 1989-90 heat-
ing seasons, PM and CO emissions of 18
certified woodburning stoves representing
eight models (six catalytic, two
noncatalytic) were measured. Emissions
were also measured from 18 conventional
woodburning stoves. Compared to the
emissions measured from conventional
stoves, the 18 certified stoves reduced
PM and CO by a factor of about 2 (50%
reduction).
There was a difference in the perfor-
mance of the two low emission technolo-
gies, catalytic and noncatalytic. PM re-
duction was about the same for both tech-
nologies, but CO reduction was greater
for the catalytic stoves.
There were significant differences be-
the two models is not straightforward, since
two of the three model H stoves were
operated at low burn rates compared to
the burn rates for the two model G stoves.
The noncatalytic models performed best
at higher burn rates, and the data suggest
that operators be encouraged to operate
at burn rates averaging 0.9 kg/hr of dry
wood or more.
All the catalytic stove models had re-
duced emissions compared to the con-
ventional stoves. The average PM emis-
sion factor reduction for the catalytic mod-
els ranged from 34 to 71%, while CO
reduction ranged from 41 to 64%. There
is currently not enough data to determine
the reasons for differences in performance.
The hand-fired coalstove was cleaner than
expected. On a gram/pule basis, the PM
tween-the-performance=of= different-stove—^mission factorsJwere^redueed-by-SB^epnv _„»«
models within a technology. In most cases
additional measurements and/or stove in-
spection might reveal the causes.
Both noncatalytic stove models tested
had reduced emissions compared to con-
ventional stoves. For model G, average
PM and CO reductions were 71 and 48%
respectively, and for model H the reduc-
tions were 44 and 19%. Comparison of
pared to conventional woodstoves. The CO
emissbns were reduced by about 27%. Since
only one hand-fired stove was monitored, it is
not possible to say whether its behavior is
average when compared to other hand-fired
coalburning stoves. The two automatically
stoked coal appliances were very dean com-
pared to the conventional stoves monitored.
Average PM reductions were 84% and aver-
age CO reductions were 85%.
D. Jaasma, M. Champion, and M. Gundappa are with Virginia Polytechnic
Institute and State University, Blacksburg, Va 24061-0238
Robert C. McCrlllls is the EPA Project Officer (see below).
The complete report, entitled "Field Performance of Woodburning and
Coalburning Appliances in Crested Butte During the 1989-1990 Heating
Season," (Order No. PB91-106921/AS; Cost: $26.00, subject to change) will
be available only from:
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Telephone: 703-487-4650
The EPA Project Off her can be contacted at:
Air and Energy Engineering Research Laboratory
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
United States
Environmental Protection
Agency
Center for Environmental
Research Information
Cincinnati, OH 45268
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EPA/600/S7-91/005
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