SRI/USEPA-GHG-VR-45 vl.6
May 2012
SRI/USEPA-GHG-VR-45
May 2012
Version 1.6
Environmental Technology
Verification Report
Building Energy Solutions, LLC
Tecogen CM-100 Combined Heat and
Power System
Greenhouse Gas Technology Center
Operated by
SOUTHERN RESEARCH Southern Research Institute
INSTITUTE
Under a Cooperative Agreement With
U.S. Environmental Protection Agency
and
Under Agreement With
IWSEHDA New York State Energy Research and Development Authority
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SRI/USEPA-GHG-VR-45 vl.6
May 2012
EPA REVIEW NOTICE
This report has been peer and administratively reviewed by the U.S. Environmental Protection Agency, and
approved for publication. Mention of trade names or commercial products does not constitute endorsement or
recommendation for use.
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SRI/USEPA-GHG-VR-45 vl.6
May 2012
THE ENVIRONMENTAL TECHNOLOGY VERIFICATION PROGRAM
ET/
NY5ERDA
SOUTHERN RESEARCH
Legendary Discoveries. Leading Innovation.
ETV Joint Verification Statement
TECHNOLOGY TYPE: Electric Power and Heat Production using Natural Gas
APPLICATION: Combined Heat and Power System
TECHNOLOGY NAME: Tecogen Model CM-100
COMPANY: Tecogen
ADDRESS' 45 First Avenue
Waltham, MA 02451
WEB ADDRESS: http://www.tecogen.com/
The U.S. Environmental Protection Agency's Office of Research and Development (EPA-ORD) operates
the Environmental Technology Verification (ETV) program to facilitate the deployment of innovative
technologies through performance verification and information dissemination. The goal of ETV is to
further environmental protection by accelerating the acceptance and use of improved and innovative
environmental technologies. ETV seeks to achieve this goal by providing high-quality, peer-reviewed
data on technology performance to those involved in the purchase, design, distribution, financing,
permitting, and use of environmental technologies.
ETV works in partnership with recognized standards and testing organizations, stakeholder groups that
consist of buyers, vendor organizations, and permitters, and with the full participation of individual
technology developers. The program evaluates the performance of technologies by developing test plans
that are responsive to the needs of stakeholders, conducting field or laboratory tests, collecting and
analyzing data, and preparing peer-reviewed reports. All evaluations are conducted in accordance with
rigorous quality assurance protocols to ensure that data of known and adequate quality are generated and
that the results are defensible.
The Greenhouse Gas Technology Center (GHG Center), operated by Southern Research Institute
(Southern), is one of six verification organizations operating under the ETV program. A technology area
of interest to some GHG Center stakeholders is distributed electrical power generation (DG), particularly
with combined heat and power (CHP) capabilities.
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May 2012
The GHG Center collaborated with the New York State Energy Research and Development Authority
(NYSERDA) to evaluate the performance of an array of six Tecogen Model CM-100 units - combined
heat and power (CHP) system manufactured by Tecogen and fueled with natural gas. The system is
owned and operated by BOCES in Verona, New York.
TECHNOLOGY DESCRIPTION
The following information has been supplied by the vendor and has not been verified. Building Energy
Solutions (BES) has installed six natural gas-fired Tecogen Model CM-100 Premium Power CHP
modules as part of a DG / CHP upgrade at the Madison-Oneida Board of Cooperative Educational
Services (BOCES) campus located in Verona, NY. The technical basis for the technology is as follows.
The Tecogen system utilizes natural gas fuel, combusted in an internal combustion engine, which is used
to drive an electric generator. Thermal energy in the engine's exhaust heat and other heat sources is
recovered and used for various purposes. The CHP array operates in response to the site's electrical
demand; power is not exported to the grid. Management of the host facility's peak electrical demand is a
fundamental economic driver for the system.
The installation recovers thermal energy from the 1C engine jacket coolant, oil cooler, and exhaust. The
recovered energy is designed to supply up to 4.4 million British thermal units per hour (MMBtu/h) from
the array of six units to the following district heating and cooling applications:
year-round domestic hot water (DHW)
heat supply to two 100-ton absorption chillers for air-conditioning during warm weather
hydronic space heating during cold weather
The facility also incorporates two 7500-gallon insulated thermal storage tanks. Their function is to
provide approximately 2.5 MMBtu carry-through capacity for space heating and DHW needs during cold
weather periods when electrical demand is low.
The CHP heating and cooling applications displace fuel consumption by five existing natural gas-fired
boilers rated atl.94 MMBtu/h each. Two of the boilers are located adjacent to the CHP installation while
the remaining three are located elsewhere on the campus. Hydronic heating, DHW, and chilled water
piping is generally located in the ceiling spaces and corridors which connect the various building sections.
The electrical generators, panel boards, circulation pumps, and most other parasitic loads are connected to
the main service bus located in the building "Section H" mechanical room.
VERIFICATION DESCRIPTION
Rationale for the experimental design, determination of verification parameters, detailed testing
procedures, test log forms, and QA/QC procedures can be found in the draft ETV Generic Verification
Protocol (GVP) [3] for DG/CHP verifications developed by the GHG Center. Site specific information
and details regarding instrumentation, procedures, and measurements specific to this verification were
detailed in the Test and Quality Assurance Plan titled Test and Quality Assurance Plan - Building Energy
Soulutions, LLC Tecogen DG / CHP Installation. Both can be downloaded from the ETV Program web-
site (www. epa.gov/etv).
Controlled Testing
Controlled testing for the field testing was conducted on September 9, 2009 through September 11th,
2009. The defined system under test (SUT) was tested to determine performance for the following
verification parameters:
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Electrical Performance
Electrical Efficiency
CHP Thermal Performance
CHP Thermal Efficiency
Atmospheric Emissions (controlled test period only).
NOX and CO2 emissions reductions (offsets) relative to baseline conditions
Electrical and thermal performance and efficiency were quantified following the rationale and approaches
detailed in the GVP. Specifically, electrical generation efficiency can also be termed the "fuel-to-
electricity conversion efficiency." It is the net amount of energy a system produces as electricity
compared to the amount of energy input to the system in the fuel. Heat rate expresses electrical generation
efficiency in terms of British thermal units per kW-hour (Btu/kWh). For determination of thermal
performance, applicable CHP devices use a circulating liquid heat transfer fluid for heating or chilling.
The CHP equipment itself is considered to be within the SUT boundary. The balance of plant (BoP)
equipment, which employs the heating or chilling effect, is outside the system boundary. The GVP does
not consider how efficiently the BoP uses the heating or chilling effect. Actual thermal performance is the
heat transferred out of the SUT boundary to the BoP for both CHP heaters and chillers. Actual thermal
efficiency in heating service is the ratio of the thermal performance to total heat input in the fuel. Detailed
definitions and equations appear in Appendix C of the GVP.
The verification included a series of controlled test periods on September 10, 2009 in which the GHG
Center maintained steady system operations for three test periods at loads of 100%, 75%, and 50% of
capacity (100, 75, and 50 kW, respectively) on one of the six Tecogen CM 100 units. Equipment tag
name, Cogen 4 was selected from the six units to evaluate electrical and CHP efficiency and emissions
performance. Testing took place at night so it would not interfere with normal operations of the facility.
Five of the six units were shutdown during the controlled test period and temporary installation of
independent electrical power analyzers were placed on the Cogen 4 output bus. The analyzers recorded
the electrical performance parameters at 1-minute intervals. Water serves as the CHP heat transfer fluid.
Southern installed supply and return temperature sensors and an ultrasonic fluid flow meter to determine
heat recovery from the CHP system heat recovery loop.
Emissions data were recorded from the Cogen 4 exhaust stack on the roof of the mechanical room.
Southern's Horiba OBS-2200 PEMS (Portable Emissions Monitoring System) was installed on the
exhaust stack to measure atmospheric emissions including THC, CO, CO2, and NOX. Other parameters
including exhaust flow, exhaust temperature, exhaust pressure, moisture, ambient temperature, and
ambient pressure were also collected from the OBS-2200 to allow for computing exhaust gas flow at dry,
standard conditions. Fuel gas consumption was determined by a data logger connected to a revenue-grade
gas meter. Southern installed a Dresser brand Roots meter (model 11M175) in the CHP array gas line.
The meter incorporates a high-frequency pulse output for flow rate determinations. Test personnel
connected the meter output to the data logger and recorded the gas flow rate at least once per minute
during all test periods. Testing personnel also temporarily installed ports for collecting natural gas
samples for lower heating value (LHV) analysis.
Long-term Monitoring
The controlled tests were followed by a 1 year period of continuous monitoring to determine heat
recovery and power output, electrical and thermal efficiency, and estimated annual emission reductions
on the full array of six CHP units under normal operation.
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May 2012
Quality Assurance
Quality assurance (QA) oversight of the verification testing was provided following specifications in the
ETV Quality Management Plan (QMP). On September 10th 2009, the EPA conducted a Technical
Systems Audit on site. Bob Wright from EPA and David Gratson from Neptune and Company, Inc
conducted the audit while controlled testing was underway. The GHG Center's QA manager conducted
an audit of data quality on the data generated during this verification and a review of this report. Data
review and validation was conducted at three levels including the field team leader, the project manager,
and the QA manager.
VERIFICATION OF PERFORMANCE
Electrical and Thermal Performance - Controlled Test Period
Gross and net electrical performance and efficiency as measured during the controlled test period are
presented in Table 1. Net electrical performance is exclusive of power consumed by CHP system
electrical loads required for system operation (parasitic loads). Parasitic loads are disproportionally high
during the controlled test period when only one unit is operating as compared to normal operations when
up to six cogeneration units may be operating. Parasitic loads during the controlled test period averaged
about 7 percent of gross power output, whereas during the long term monitoring, parasitic loads averaged
only 2-4 percent of gross power output (depending on load conditions). Uncertainties given in table 1
were determined by measurement error propagation as detailed in Section 7 of the GVP.
Thermal performance as measured during the controlled test period is not reported. The thermal
performance measurements are not considered representative for several reasons. The heat recovery fluid
flow measurement is not considered reliable because the flow velocities with only a single unit operating
were at or below the velocity at which the instrument accuracy rapidly deteriorates. Heat losses with only
a single unit operating are disproportionately high compared to normal operations with up to six units
operating. System controls, which seek to maintain the return temperature to the cogeneration array at a
constant level, did not appear to be able to operate as intended with only a single unit operating, resulting
in cycling of flow rate and return temperature. A detailed assessment of these factors is provided in
section 3.2.3 of the full verification report.
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May 2012
Table 1. Controlled Test Electrical and Thermal Performance
Test ID
100
kW
75
kW
50
kW
Runl
Run 2
Run3
Avg.
+/-
Runl
Run 2
Run 3
Avg.
+/-
Runl
Run 2
Run3
Avg.
+/-
Heat Input
(MMBtu/h)
1.18
1.17
1.17
1.18
1.8%
0.85
0.85
0.86
0.86
1.8%
0.57
0.57
0.58
0.58
1.8%
Electrical Power Generation Performance
Net Power
Generated
(kW)
91.8
91.2
91.4
91.5
0.7%
66.2
66.1
66.5
66.3
0.7%
41.6
41.4
42.8
41.9
0.7%
Net
Electrical
Efficiency
(%)
26.5
26.6
26.6
26.6
3.0%
26.5
26.4
26.4
26.4
3.0%
24.7
24.6
25.2
24.8
3.0%
Gross
Power
Generated
(kW)
98.0
97.3
97.7
97.7
0.7%
72.3
72.3
72.6
72.4
0.7%
47.3
47.2
47.5
47.3
0.7%
Gross
Electrical
Efficiency
(%)
28.3
28.4
28.4
28.4
3.0%
28.9
28.9
28.8
28.9
3.0%
28.1
28.0
28.0
28.0
3.0%
Reported uncertainties by measurement error propagation per GVP in percentage
of reported value. Net electrical performance is exclusive of electrical loads
required for system operation (parasitic loads). Parasitic loads are
disproportionately high during the controlled test conditions as described above.
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May 2012
Emissions Performance - Controlled Test Period
Table 2 summarizes emissions performance of the Cogen 4 unit during the controlled test period.
THC and NOX emissions at the 50kW load condition are elevated. This is due to poor engine
performance at partial load - an abnormal operating condition. In normal operations, the units are run at
greater than 60 percent load and individual units are taken on and off line in response to facility electrical
demand.
Uncertainties given in this table were determined by calculating a 95 percent confidence interval over the
mean of all three runs at each load condition. The higher uncertainty for CO emissions at the 75kW load
conditions is due to a greater degree of fluctuation in CO concentration at the lower load conditions. CO
emissions measurements for the 50kW load condition were invalidated and are not reported. The
analyzer failed the span drift check at the conclusion of the test run, and examination of the data showed
that negative values were frequently reported.
Power Quality Performance - Controlled Test Period
Power quality was not monitored during the controlled test period due to a malfunction of data logging
equipment. This is not considered to have a significant impact on the quality of the performance
verification as power quality is proven to be sufficient for grid interconnect.
Electrical and Thermal Performance - Long Term Monitoring Period
Measurements necessary to determine electrical and thermal performance and efficiency were collected
over a period from September 2009 through September 2010. Table 3 provides a summary of the results.
During normal operations at the BOCES facility, the cogeneration array operates in response to electrical
demand. As such, the array typically operates at nearly full load during weekdays, with partial load at
nights and on weekends. Full load conditions are characterized by power generation rates over 300kW,
and night/weekend conditions are characterized by generation rates less than 300 kW. The cogeneration
array operated nearly continuously throughout the year of monitoring, with only one brief period of down
time (43 hours) in late June 2010.
Gross electrical efficiency during the extended test was 24.1 percent on an annual basis, 26.4 percent at
full load conditions, and 22 percent at partial load conditions. Parasitic loads accounted for 2 to 4 percent
of power production depending on load conditions.
As can be seen in Table 3, the electrical and thermal efficiency of the system is somewhat lower at partial
load than at full load. The lower thermal efficiency at partial load may be due to system heat losses -
which amount to a greater proportion of the total heat recovered at partial load than at full load.
The lower electrical efficiency at partial load is not fully explained by the data. However, at the very
lowest loads (occurring during weekend daytimes), fuel consumption was consistently observed to
increase as power output decreased. This could be due to the cogeneration array running in an inefficient
operating range at the lowest load conditions. During the controlled tests with only one of six units
operating, electrical efficiency decreased slightly at the 50 percent load condition, but not as much as was
observed during extended monitoring of the full cogeneration array.
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May 20 12
Table 2. Tecogen Emissions During Controlled Test Periods
Test ID
lOOkW
75 kW
50 kW
Runl
Run 2
Run3
Avg.
95% CI
Runl
Run 2
Run3
Avg.
95% CI
Runl
Run 2
RunS
Avg.
95% CI
Test ID
lOOkW
75 kW
50 kW
Runl
Run 2
RunS
Avg.
95% CI
Runl
Run 2
RunS
Avg.
95% CI
Runl
Run 2
RunS
Avg.
95% CI
Gross
Power
(kW)
98
97
98
98
72
72
73
72
47
47
48
47
Gross
Power
(kW)
98
97
98
98
72
72
73
72
47
47
48
47
CO Emissions
ppm
175
162
168
168
1.7%
44
81
96
74
5.3%
not reported*
not reported*
not reported*
Ib/hr
0.17
0.16
0.16
0.17
0.04
0.08
0.09
0.07
0.06
0.08
0.09
0.08
Ib/MWh
1.8
1.6
1.7
1.7
0.5
1.1
1.2
0.9
1.4
1.7
1.8
1.6
THC Emissions
ppm
5.7
4.8
4.9
5.1
1.2%
8.8
8.5
8.7
5.8
2.3%
273
288
292
284
1.5%
Ib/hr
0.006
0.005
0.005
0.005
0.008
0.008
0.008
0.008
0.154
0.185
0.201
0.180
Ib/MWh
0.06
0.05
0.05
0.05
0.11
0.11
0.11
0.11
3.2
3.9
4.2
3.8
CO2 Emissions
Volume %
9.3
9.2
9.2
9.2
0.02%
9.1
9.1
9.1
9.1
0.06%
9.2
9.2
9.2
9.2
0.07%
Ib/hr
91
90
91
91
80
85
86
84
52
59
63
58
Ib/MWh
930
927
928
928
1113
1182
1180
1158
1095
1250
1328
1224
NOx Emissions
ppm
12.8
12.9
13.1
12.9
2.5%
8.4
8.3
7.8
5.6
4.0%
843
881
881
869
1.6%
Ib/hr
0.013
0.013
0.013
0.013
0.007
0.008
0.007
0.008
0.475
0.567
0.608
0.550
Ib/MWh
0.1
0.1
0.1
0.1
0.1
0.1
0.1
0.1
10.0
12.0
12.8
11.6
*Carbon monoxide results for the 50 percent load condition are not reported because the instrument failed the span drift check
at the conclusion of the testing at this condition and the results appeared suspect upon examination (concentrations during the
run were frequently recorded as negative values).
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May 2012
Table 3. Extended Test Results Summary
Annual
Average
Full Load -
(Weekday)
(>=300kW)
Partial
Load-
(Night)
(<300kW)
Average
Net
Power
Output
(kW)
293
394
211
+/-
0.7%
0.7%
0.7%
Average
Heat
Recovery
(MMBtu/hr)
2.26
2.98
1.68
+/-
4.4%
4.4%
4.4%
Average
Thermal
Efficiency
(%)
53.7
60.4
48.2
+/-
4.9%
4.9%
4.9%
Average
Net
Electrical
Efficiency
(%)
23.5
25.8
21.3
+/-
3.0%
3.0%
3.0%
Average
Total
Efficiency
(%)
77.2
86.2
69.5
+/-
3.5%
3.5%
3.5%
Reported uncertainties by measurement error propagation per GVP.
Signed by Cynthia Sonich-Mullin
(3/7/2013)
Cynthia Sonich-Mullin
Director
National Risk Management Research Laboratory
Office of Research and Development
Signed by Tim Hansen
(1/3/2013)
Tim Hansen
Director
Greenhouse Gas Technology Center
Southern Research Institute
Notice: GHG Center verifications are based on an evaluation of technology performance under specific,
predetermined criteria and the appropriate quality assurance procedures. The EPA and Southern Research Institute
make no expressed or implied warranties as to the performance of the technology and do not certify that a
technology will always operate at the levels verified. The end user is solely responsible for complying with any and
all applicable Federal, State, and Local requirements. Mention of commercial product names does not imply
endorsement or recommendation.
EPA REVIEW NOTICE
This report has been peer and administratively reviewed by the U.S. Environmental Protection Agency, and
approved for publication. Mention of trade names or commercial products does not constitute endorsement or
recommendation for use.
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SRI/USEPA-GHG-VR-45
May, 2012
Greenhouse Gas Technology Center
A U.S. EPA Sponsored Environmental Technology Verification ( £j^ ) Organization
Environmental Technology Verification Report
Building Energy Solutions, LLP Tecogen CM-100 Combined
Heat and Power System
Prepared By:
Greenhouse Gas Technology Center
Southern Research Institute
5201 International Drive
Durham, NC 27712 USA
Telephone: 919-282-1050
Under EPA Cooperative Agreement R-82947801
and NYSERDA Agreement 7009
U.S. Environmental Protection Agency
Office of Research and Development
National Risk Management Research Laboratory
Air Pollution Prevention and Control Division
Research Triangle Park, NC 27711 USA
EPA Project Officer: Lee Beck
NYSERDA Project Officer: Greg Pedrick
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TABLE OF CONTENTS
Page
LIST OF FIGURES ii
LIST OF TABLES ii
ACKNOWLEDGMENTS ii
ACRONYMS AND ABBREVIATIONS iii
1.0 INTRODUCTION 1
1.1. BACKGROUND 1
1.2. BOCES TECOGEN DG/CHP TECHNOLOGY DESCPJPTION 2
1.3. PERFORMANCE VERIFICATION OVERVIEW 3
1.3.1. Electrical Performance (GVP §2.0) 6
1.3.2. Electrical Efficiency (GVP §3.0) 6
1.3.3. CHP Thermal Performance (GVP §4.0) 7
1.3.4. Emissions Performance (GVP §5.0) 7
1.3.5. Field Test Procedures and Site Specific Instrumentation 8
1.3.6. Estimated NOX and CO2 Offset Emission Reductions 11
2.0 VERIFICATION RESULTS 12
2.1. ELECTRICAL AND THERMAL PERFORMANCE AND EFFICIENCY 12
2.1.1. Controlled Test Results 12
2.1.2. Long Term Test Results 15
2.2. POWER QUALITY PERFORMANCE 16
2.3. EMISSIONS PERFORMANCE 16
2.3.1. Emissions Test Results 16
2.4. ESTIMATION OF ANNUAL NOX AND CO2 EMISSION REDUCTIONS 17
3.0 DATA QUALITY ASSESSMENT 19
3.1. DATA QUALITY OBJECTIVES 19
3.2. DOCUMENTATION OF MEASUREMENT QUALITY OBJECTIVES 20
3.2.1. Electrical Generation Performance 21
3.2.2. Electrical Efficiency Performance 21
3.2.3. CHP Thermal Efficiency Performance 22
3.2.4. Emissions Measurement MQOs 23
3.3. AUDITS 24
4.0 REFERENCES 25
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Figure 1-1
Figure 1-2
Figure 1-3
Figure 3-1
LIST OF FIGURES
Pas
BOCES in Verona, New York 3
BOCES DG/CHP System Boundary Diagram 4
System Boundary Diagram - Extended Monitoring Period 5
Periodic Variation in Controlled Test Heat Recovery Data 23
Table 1-1
Table 1-2
Table 2-1
Table 2-2
Table 2-3
Table 2-4
Table 2-5
Table 2-6
Table 2-7
Table 3-1
Table 3-2
Table 3-3
Table 3-4
LIST OF TABLES
Page
Controlled and Extended Test Periods 6
Site Specific Instrumentation for BOCES DG/CHP System Verification 10
Variability in Operating Conditions During Controlled Test Periods 13
BOCES DG/CHP System Ambient Conditions during Controlled Tests 13
BOCES DG/CHP System Electrical and Thermal Performance 14
BOCES DG/CHP System Heat Input Determination 15
Extended Monitoring Results Summary 16
BOCES DG/CHP System Emissions during Controlled Test Periods 17
Estimation of Emission Reductions at BOCES 18
Electrical Generation Performance MQOs 21
Electrical Efficiency MQOs 22
CHP Thermal Efficiency MQOs 22
Summary of Emissions Testing Calibrations and QA/QC Checks 24
ACKNOWLEDGMENTS
The Greenhouse Gas Technology Center wishes to thank NYSERDA, especially Jim Foster, for
supporting this verification and reviewing and providing input on the testing strategy and this Verification
Report. Thanks are also extended to Madison-Oneida Board of Cooperative Educational Services
(BOCES) campus, and Todd Vandresser for his input supporting the verification and assistance with field
testing activities. Thanks also go out to CDH Energy Corp., specifically Adam Walburger, for his
assistance with field testing activities. Finally, many thanks are due to Rae Butler of Building Energy
Solutions for supplementing the long term monitoring data with data from BOCES system sensors and to
Joe Gehret or Tecogen for his assistance in data interpretation.
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ADQ
BBS
BOCES
Btu/h
Btu/scf
CHP
CO
CO2
CT
DG
DHW
DQO
OUT
EPA
ETV
FID
FS
GHG Center
GVP
gpm
Hz
kVA
kVAR
kW
kWh
Ib/h
Ib/kWh
Ib/MWh
LHV
MMBtu/h
MQO
MWh
NDIR
NIST
NOX
NYSERDA
O2
PEMS
ppm
psia
QA/QC
QMP
RTD
scfh
SUT
TQAP
THCs
THD
ACRONYMS AND ABBREVIATIONS
Audit of Data Quality
Building Energy Solutions
Board of Cooperative Educational Services
British thermal units per hour
British thermal units per standard cubic feet
combined heat and power
carbon monoxide
carbon dioxide
current transformer
distributed generation
domestic hot water
data quality objective
device under test
Environmental Protection Agency
Environmental Technology Verification
flame ionization detector
full scale
Greenhouse Gas Technology Center
generic verification protocol
gallons per minute
hertz
kilovolt-amperes
kilovolt-amperes reactive
kilowatts
kilowatt hours
pounds per hour
pounds per kilowatt-hour
pounds per megawatt-hour
lower heating value
million British thermal units per hour
measurement quality objective
megawatt-hour
non-dispersive infra-red
National Institute of Standards and Technology
nitrogen oxides
New York State Energy Research and Development Authority
oxygen
portable emissions measurement system
parts per million volume, dry
pounds per square inch, absolute
Quality Assurance/Quality Control
Quality Management Plan
resistance temperature detector
standard cubic feet per hour
system under test
Test and Quality Assurance Plan
total hydrocarbons
total harmonic distortion
in
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1.0 INTRODUCTION
1.1. BACKGROUND
The U.S. Environmental Protection Agency's Office of Research and Development (EPA-ORD) operates the
Environmental Technology Verification (ETV) program to facilitate the deployment of innovative technologies
through performance verification and information dissemination. The goal of ETV is to further environmental
protection by accelerating the acceptance and use of improved and innovative environmental technologies.
Congress funds ETV in response to the belief that there are many viable environmental technologies that are not
being used for the lack of credible third-party performance data. With performance data developed under this
program, technology buyers, financiers, and permitters in the United States and abroad will be better equipped to
make informed decisions regarding environmental technology purchase and use.
The Greenhouse Gas Technology Center (GHG Center) is one of six verification organizations operating under the
ETV program. The GHG Center is managed by EPA's partner verification organization, Southern Research
Institute (Southern), which conducts verification testing of promising greenhouse gas mitigation and monitoring
technologies. The GHG Center's verification process consists of developing verification protocols, conducting
field tests, collecting and interpreting field and other data, obtaining independent stakeholder input, and reporting
findings. Performance evaluations are conducted according to externally reviewed verification Test and Quality
Assurance Plans (TQAPs) and established protocols for quality assurance.
The GHG Center is guided by volunteer groups of stakeholders. The GHG Center's Executive Stakeholder Group
consists of national and international experts in the areas of climate science and environmental policy, technology,
and regulation. It also includes industry trade organizations, environmental technology finance groups,
governmental organizations, and other interested groups. The GHG Center's activities are also guided by industry
specific stakeholders who provide guidance on the verification testing strategy related to their area of expertise and
peer-review key documents prepared by the GHG Center.
In recent years, a primary area of interest to GHG Center stakeholders has been distributed electrical power
generation systems. Distributed generation (DG) refers to equipment, typically ranging from 1 to 1,000 kilowatts
(kW) that provide electric power at a site closer to customers than central station generation. A DG unit can be
connected directly to the customer or to a utility's transmission and distribution system. Examples of technologies
available for DG include: internal combustion engine generators; photovoltaics; wind turbines; fuel cells; and
microturbines. DG technologies provide customers one or more of the following main services: standby
generation; peak shaving generation; base load generation; or cogeneration. DG systems that utilize renewable
energy sources can provide even greater environmental and economic benefits.
Since 2002, the GHG Center and the New York State Energy Research and Development Authority (NYSERDA)
have collaborated and shared the cost of verifying several new DG technologies throughout the state of New York
under NYSERDA-sponsored programs. The verification described in this document evaluated the performance of
one such DG system: an array of six natural gas-fired Tecogen Model CM-100 Premium Power combined heat and
power (CHP) modules. The system is owned and operated by Madison-Oneida Board of Cooperative Educational
Services (BOCES) campus located in Verona, NY.
The GHG Center evaluated the performance of the BOCES DG/CHP system by conducting controlled field tests
over a 3-day verification period (September 9, 2009 - September 11, 2010) and long term monitoring over a period
of one year beginning at the conclusion of the controlled testing and ending September 30, 2010. These tests were
planned and executed by the GHG Center to independently verify electricity generation rate, thermal energy
recovery rate, electrical power quality, energy efficiency, emissions, and greenhouse gas emission reductions for a
six unit array DG/CHP system as operated at BOCES. In order to avoid the cost and complexity of measuring
1
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emissions from each of the six separate exhaust stacks, the controlled tests focused on a single selected unit from
the array.
Details on the verification test design, measurement test procedures, and quality assurance/quality control (QA/QC)
procedures are contained in two related documents. Technology and site specific information can be found in the
document titled Test and Quality Assurance Plan - Building Energy Solutuions, LLP Tecogen DG / CHP
Installation\Y\. It can be downloaded from the GHG Center's web-site (www.sri-rtp.com) or the ETV Program
web-site (www.epa.gov/etv). This TQAP describes the system under test (SUT), project participants, site specific
instrumentation and measurements, and verification specific QA/QC goals. The TQAP was reviewed and revised
based on comments received from NYSERDA, and the EPA Quality Assurance Team. The TQAP meets the
requirements of the GHG Center's Quality Management Plan (QMP) and satisfies ETV QMP requirements.
Rationale for the experimental design, determination of verification parameters, detailed testing procedures, test log
forms, and QA/QC procedures can be found in the Association of State Energy Research and Technology Transfer
Institutions (ASERTTI) DG/CHP Distributed Generation and Combined Heat and Power Performance Protocol for
Field Testing [2]. This document can be downloaded from the web location
www.dgdata.org/pdfs/field_protocol.pdf The GHG Center has adopted portions of this protocol as a generic
verification protocol (GVP) for DG/CHP verifications [3]. This ETV performance verification of the Tecogen
system was based on the GVP.
The remainder of Section 1.0 describes the BOCES DG/CHP system technology and test facility, and outlines the
performance verification procedures that were followed. Section 2.0 presents test results, and Section 3.0 assesses
the quality of the data obtained.
1.2. BOCES TECOGEN DG/CHP TECHNOLOGY DESCRIPTION
The following information has been supplied by the vendor and has not been verified. Building Energy Solutions
(BES) has installed six natural gas-fired Tecogen Model CM-100 Premium Power CHP modules as part of a DG /
CHP upgrade at the Madison-Oneida Board of Cooperative Educational Services (BOCES) campus located in
Verona, NY. The technical basis for the technology is as follows.
The CHP array operates in response to the site's electrical demand; power is not exported to the grid. Management
of the host facility's peak electrical demand, is a fundamental economic driver for the system.
The installation recovers thermal energy from the 1C engine jacket coolant, oil cooler, and exhaust. The recovered
energy is designed to supply up to 4.4 million British thermal units per hour (MMBtu/h) from the array of six units
to the following district heating and cooling applications:
year-round domestic hot water (DHW)
heat supply to two 100-ton absorption chillers for air-conditioning during warm weather
hydronic space heating during cold weather
The facility also incorporates two 7500-gallon insulated thermal storage tanks. Their function is to provide
approximately 2.5 MMBtu carry-through capacity for space heating and DHW needs during cold weather periods
when electrical demand is low.
The CHP heating and cooling application displaces fuel consumption at five existing natural gas-fired boilers rated
at 1.94 MMBtu/h each. Two of the boilers are located adjacent to the CHP installation while the remaining three
are located elsewhere on the campus. Hydronic heating, DHW, and chilled water piping is generally located in the
ceiling spaces and corridors which connect the various building sections. The electrical generators, panel boards,
circulation pumps, and most other parasitic loads are connected to the main service bus located in the building
"Section H" mechanical room.
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Figure 1-1. BOCES in Verona, New York
1.3. PERFORMANCE VERIFICATION OVERVIEW
The verification included evaluation of the DG/CHP system performance over a series of controlled test periods on
a single unit of the six unit array. The GVP specifies testing at three loads: 100%, 75%, and 50% of capacity (100,
75, and 50 kW, respectively). In addition to the controlled test periods, the test plan specifies that one year of
continuous fuel consumption, power generation, and heat recovery data be collected to characterize the system
performance of the six unit array over normal facility operations. Southern Research and its subcontractor, CDH
Energy Corp., installed instrumentation and provided data acquisition/telemetry equipment during the long term
monitoring period. Long term monitoring data was supplemented by data from the BOCES building management
system provided by Building Energy Solutions.
BOCES verification was limited to the performance of the system under test (SUT) within a defined system
boundary that includes the Tecogen units and supply and return lines from the hot water storage tanks and heat
rejection air handling unit. Figure 1-2 illustrates the system boundary and monitoring configuration for the
controled test period. Figure 1-3 illustrates the system boundary and monitoring configuration for the long-term
test period.
Electrical and thermal performance and efficiency were quantified following the rationale and approaches detailed
in the GVP. Specifically, electrical generation efficiency can also be termed the "fuel-to-electricity conversion
efficiency." It is the net amount of energy a system produces as electricity compared to the amount of energy input
to the system in the fuel. Heat rate expresses electrical generation efficiency in terms of British thermal units per
kW-hour (Btu/kWh). For determination of thermal performance, applicable CHP devices use a circulating liquid
heat transfer fluid for heating or chilling. The CHP equipment itself is considered to be within the SUT boundary.
The balance of plant (BoP) equipment, which employs the heating or chilling effect, is outside the system
boundary. The GVP does not consider how efficiently the BoP uses the heating or chilling effect. Actual thermal
performance is the heat transferred out of the SUT boundary to the BoP for both CHP heaters and chillers. Actual
thermal efficiency in heating service is the ratio of the thermal performance to total heat input in the fuel. Detailed
definitions and equations appear in Appendix C of the GVP.
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Figure 1-2. System Boundary Diagram - Controlled Test Period
Gross Power
Output
Net Power Output
(Pwr_Gen_Neg)
Exhaust . Emissions Measurements
Vol, std
CO, CO2,
NOx, THC,
H20, Pamb
-o
f~\ NOx, THC, O2
CHP Water Circulation
and Standby Pumps
(P-H-CGD 1/2)
Grid Interconnect
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CHP Water Circulation
and Standby Pumps
(P-H-CGD 1/2)
Supply
Return
Generator and Electronics
Cooling
Qfuel, Btu/scf Vfuel- scfm
Net Power Output
(Pwr_Gen_Neg)
Heat Rejection
Air Handler I
Controls
MCC-2
Grid Interconnect
Figure 1-3. System Boundary Diagram - Extended Monitoring Period
The SUT was tested to determine performance for the following verification parameters:
Electrical Performance
Electrical Efficiency
CHP Thermal Performance
CHP Thermal Efficiency
Atmospheric Emissions (controlled test period only).
NOX and CO2 emissions reductions (offsets) relative to baseline conditions
Each of the verification parameters listed above was evaluated during the controlled or extended monitoring periods
as summarized in Table 1-1. This table also specifies the dates and time periods during which the testing was
conducted. Simultaneous monitoring for power output, heat recovery rate, heat input, ambient meteorological
conditions, and exhaust emissions was performed during each of the controlled test periods. Fuel gas samples were
collected to determine fuel lower heating value and other gas properties. Average electrical power output, heat
recovery rate, energy conversion efficiency (electrical, thermal, and total), and exhaust emission rates are reported
for each test period.
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Table 1-1. Controlled and Extended Test Periods
Controlled Test Periods
Start Date,
Time
09/10/2009,
00:25
09/10/2009,
02:05
09/10/2009,
03:45
End Date,
Time
09/10/2009,
01:55
09/10/2009,
03:35
09/10/2009,
05:15
Test Condition
Power command 100 kW, three 30 minute test runs
Power command 75 kW, three 30 minute test runs
Power command 50 kW, three 30 minute test runs
Verification Parameters
Evaluated
NOX, CO, CO2, and THC emissions;
electrical, thermal, and CHP
efficiency.
NOX, CO, CO2, and THC emissions;
electrical, thermal, and CHP
efficiency.
NOX, CO, CO2, and THC emissions;
electrical, thermal, and CHP
efficiency.
Extended Test Period
Start Date
0912/2009
End Date
09/12/2010
Test Condition
Unit operated at normal power
command
Verification Parameters Evaluated
Electricity generated; electrical, thermal, and
CHP efficiency; emission offsets.
The following sections identify the sections of the GVP that were followed during this verification, identify site
specific instrumentation for each, and specify any exceptions or deviations from the TQAP that occurred.
1.3.1. Electrical Performance
Determination of electrical performance was conducted following §2.0 and Appendix D 1.0 of the GVP. The
following parameters were measured:
net real power produced (less parasitic loads), kW
voltage (for each phase and average of all three phases), volts (V) (controlled period only)
current (for each phase and average of all three phases), amperes (A) (controlled period only)
Measurements of the following parameters were planned for the controlled test period, but were not obtained due to
a malfunction in the data logging equipment. This is not considered to have a significant impact on data quality
since the power quality is known to be acceptable for grid interconnection.
total reactive power, KVA reactive
total power factor, percent
frequency, Hertz (Hz)
1.3.2. Electrical Efficiency
Determination of electrical efficiency was conducted following §3.0 and Appendix D2.0 of the GVP. The
following parameters were calculated:
net power output, kW
fuel input, standard cubic feet per hour (scfh)
heat input (Qm), British thermal units per hour (Btu/h)
net electrical generation efficiency (TI^LHV) including external parasitic loads
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Net real power production (excluding parasitic loads) was measured by the Power Measurements Ltd. Digital
power meter. The power meter installation was such that power was measured after parasitic loads were taken off
the circuit.
Fuel gas flow to the CHP units was measured by a Dresser brand Roots meter, model 11M175 with a specified
accuracy of ± 1 percent. Three gas samples were collected and shipped to Empact Analytical of Brighton, Colorado
for LHV analysis according to ASTM Method 1945.
1.3.3. CHP Thermal Performance
Determination of CHP thermal performance was conducted following §4.0 and Appendix D3.0 of the GVP. The
following parameters were quantified:
heat transfer fluid supply and return temperatures, degrees Fahrenheit (°F),
heat recovery fluid flow rate, gallons per minute (gpm)
thermal performance (Qout), Btu/h
thermal efficiency (rjthjLHv)
To quantify these parameters, a heat recovery rate from the SUT was measured on the heat transfer loop. This
represents recovered heat available for use by the facility. Recovered heat actually used by the facility was not
measured as the focus of the test was on the performance of the Tecogen array independent of integration with
other building systems.
An Ultrasonic Systems Model 1010 flow meter with a nominal linear range of 0 to 40 gallons per minute (gpm)
was used to monitor flows during the controlled test period. The manufacturer states that accuracy of this meter is
± 1.0 % of reading. Class A 4-wire platinum RTDs were used to determine the transfer fluid supply and return
temperatures. The specified accuracy of the RTDs is ± 0.6 °F. Pretest calibration checks documented the RTD
performance. Following Section 4.2 of the GVP, CHP performance determinations also require heat transfer fluid
density (p) and specific heat (cp). These values were obtained from standard tables for water [4].
Due to a problem with the sensor mounting, the RTDs installed by SRI/CDH ceased producing reliable data after
December 2009. Data were obtained from BBS temperature sensors in similar locations on the supply and return
lines and used for the remainder of the long term data analysis. Overlapping valid data for these sensors are
available from November 17-24 2009 and compare reasonably well (average percent difference between delta_T
from CDH and BBS data is on the order of 10%). Long term results based on the BBS sensors are considered
acceptable.
1.3.4. Emissions Performance
Determination of emissions performance was conducted following §5.0 and Appendix D4.0 of the GVP and
included emissions of nitrogen oxides (NOX), carbon monoxide (CO), carbon dioxide (CO2), and total
hydrocarbons (THC). Emissions testing was performed by GHG Center personnel using a Horiba OBS-2200
PEMS. The PEMS is essentially a miniaturized laboratory analyzer bench which has been optimized for portable
use. The instrument meets or exceeds Title 40 CFR 1065 requirements for in-use field testing of engine emissions.
This PEMS is suitable for testing a wide variety of stationary sources as well as the mobile sources for which it is
intended. Accuracy for all analytes is better than ± 2.5 % full scale (FS), while linearity is better than ± 1.0 % FS.
Exhaust gas concentrations must be integrated with exhaust gas flow rates to yield mass emission rates. The PEMS
incorporates a pitot flow tube that measures exhaust flow.
Response times for all OBS-2200 analyzers are approximately two seconds alone and five seconds with the heated
umbilical in the sample line. Test personnel established exact analyzer response times prior to testing. Software
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algorithms then align analyzer data outputs with other sensor signals, such as exhaust gas flow. Resolution depends
on the analyzer range setting, but is between four and five significant digits.
The OBS-2200 measures CO and CO2 with non-dispersive infra-red (NDIR) detectors. The OBS-2200 does not
require a separate moisture removal system for the CO and CO2 NDIR detectors. The NOX analyzer section
consists of a chemilumenescence detector with a NO2 / NO converter. This is the kind of system specified in Title
40 CFR 60, Appendix A, Method 7E, "Determination of Nitrogen Oxides Emissions from Stationary Sources",
which is a reference method for NOX.
The OBS-2200 measures THC with a flame ionization detector (FID). This method corresponds to the system
specified in Title 40 CFR 60 Appendix A, Method 25, "Determination of Total Gaseous Non-methane Organic
Emissions as Carbon", which is a reference method for THC.
The PEMS sample pump conveys all samples through a heated umbilical directly to heated analyzer sections, which
eliminates the need to remove moisture and eliminates possible errors in readings due to moisture scavenging.
Results for each pollutant are reported in units of parts per million volume, dry (ppm), pounds per hour (Ib/h), and
pounds per kilowatt-hour (Ib/MWh).
1.3.5. Field Test Procedures and Site Specific Instrumentation
Field testing followed the guidelines and procedures detailed in the following sections of the GVP:
Electrical performance - §7.1
Electrical efficiency - §7.2
CHP thermal performance and efficiency - §7.3
Emissions performance - §7.4 (controlled test only)
Controlled Testing
Controlled testing was conducted from September 9-11, 2009. The verification included a series of controlled test
periods on September 10, 2009 in which the GHG Center maintained steady system operations for three test periods
at three loads: 100%, 75%, and 50% of capacity (100, 75, and 50 kW, respectively) on one of the six Tecogen CM
100 units. Equipment unit, Cogen 4 was selected from the six units to evaluate electrical and CHP efficiency and
emissions performance. Testing took place at night so it would not interfere with normal operations of the facility.
Five of the six units were shutdown during the controlled test period and temporary electrical power analyzers were
installed on the Cogen 4 output bus. The analyzers recorded the electrical performance parameters at 1-minute
intervals. Water serves as the CHP heat transfer fluid. Southern installed supply and return temperature sensors and
an ultrasonic fluid flow meter to capture the heat recovery data. The host site has a paddlewheel flow sensor on this
heat recovery loop that was not functioning during the controlled test period.
Emissions data were recorded from Cogen 4 exhaust stack on the roof of the mechanical room. The Horiba OBS-
2200 PEMS (Portable Emissions Monitoring System) was installed on the exhaust stack to measure atmospheric
emissions including, THC, CO, CO2, and NOX. Other parameters including exhaust flow, exhaust temperature,
exhaust pressure, ambient temperature, and ambient pressure were also collected from the OBS-2200 real time at
Is/ps (sample per second). Gas consumption was determined by a datalogger connected to a revenue-grade gas
meter. Southern installed a Dresser brand Roots meter, model 11M175, in the CHP array gas line. The meter
incorporates a high-frequency pulse output for flow rate determinations. Test personnel connected the meter output
to the datalogger and recorded the gas flow rate at least once per minute during all test periods. Testing personnel
also installed ports for collecting natural gas fuel samples for lower heating value (LHV) analysis. Figure 1-1
illustrates the monitoring configuration for the controlled test period.
Long-term Monitoring
The controlled tests were followed by a 1 year period of continuous monitoring to determine heat recovery and
power output, electrical and thermal efficiency, and estimated annual emission reductions on the full array of six
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CHP units during normal facility operations. Long term measurements consisted of net real power output, fuel
consumption, and heat recovery rate. Thermal and electrical efficiency was determined from these measurements.
For the long term monitoring, a paddlewheel type flow meter was used to measure the heat recovery loop flow rate
and Wattnode power meters were used to measure gross and net power production. Data from the system's
thermistor type temperature sensors was used after the RTDs installed for the controlled test stopped functioning.
Specifications for instruments used during the controlled and extended tests is summarized in Table 1-2.
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Table 1-2. Site Specific Instrumentation for BOCES DG/CHP System Verification
Verification
Parameter
Electrical
Performance
Electrical
and Thermal
Efficiency
CHP
Thermal
Performance
Emissions
Performance
(controlled
test only)
Supporting
Measurement
Real power (gross)1
Voltage1
Current1
Real Power (net)3
Real Power
(parasitic)3
Fuel gas flow1
Fuel gas flow2
Heat transfer loop
flow1
Heat transfer loop
flow2
Heat transfer supply
temp.3
Heat transfer return
temp.3
Heat transfer supply
temp. (BES)2
Heat transfer return
temp. (BES)2
NOX concentration
CO concentration
CO2 concentration
THC concentration
Ambient temperature
Barometric pressure
Actual Range of
Measurement
45 - 100 kW
275.0 -282.0V
56- 121 A
41 -94kW
3. 8-8.5 kW
630- 1320 cfh
0 - 7800 cfh
8-24 gpm
0-170 gpm
178.0- 209.0 °F
131.0- 178.0 °F
0 - 240 °F
0 - 200 °F
0- 1650 ppmv
0 - .05%
7-11%
0-505 ppmv
55.0- 59.0 °F
14.6- 14.6psia
Instrument
Power Measurements
Ltd. ION power
meter (Model 7500)
WattNode WNB-3Y-
480
WattNode WNB-3Y-
480
Model 5M175 Roots
Meter
Model 5M175 Roots
Meter
Ultrasonic Systems
Model 10 10 flow
meter
OniconFlllO
Turbine Flowmeter
Class A 4-wire RTD
Class A 4-wire RTD
Alerton Uni-curve
Type II Thermistor
Alerton Uni-curve
Type II Thermistor
Chemiluminescence,
Horiba OBS-2200
NDIR, Horiba OBS-
2200
NDIR, Horiba OBS-
2200
FID, Horiba OBS-
2200
Horiba OBS-2200
Horiba OBS-2200
Instrument
Range
0 - 260 kW
0 - 600 V
0 - 400 A
800A CT
50ACT
0-10000
cfh
0-10000
cfh
0-100 gpm
8-800 gpm
(4 inch pipe)
0 - 250 °F
0 - 250 °F
0 - 250 °F
0 - 250 °F
0-3000
ppmv
0 - 5%
0-16 %
0-10000
ppmv
-40-185°F
0-17 psia
Instrument
Accuracy
±0.1% of
reading
±0.1% of
reading
±0.1% of
reading
± 1.0% of
reading
± 1.0% of
reading
± 1% of
reading
± 1% of
reading
± 1.0% of
reading
± 1.0% of
reading
± 0.3 °F
± 0.3 °F
± 0.5 °F
± 0.5 °F
± 2% FS
± 2% FS
± 2% FS
± 2% FS
± 0.3 °F
± 1.5%FS
Notes: 'controlled test only, Extended test only, Controlled and extended test
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1.3.6. Estimated NOX and CO2 Offset Emission Reductions
Use of the Tecogen Cogen units changes the NOX and CO2 emission rates associated with the operation of the
BOCES facility. Annual emission offsets for these pollutants are estimated and reported by subtracting emissions
of the on-site DG-CHP unit from emissions associated with baseline electrical power generation technology and
baseline space heating equipment (five, natural gas fired boilers rated at 1.94 MMBtu/hr each).
Electricity Offset
The annual electricity production from the Tecogen array of six units was determined from average net power
production in the long term data set. NOxand CO2 emissions measured from the controlled test period (at 100%
load), in which only one of the six units was running, were increased in proportion to the ratio of average power
output between the long term and controlled test periods to get a representative estimate of emissions for normal
operation. Tecogen emissions were then compared with utility emissions for New York State and Nationwide to
obtain the emissions reduction corresponding with offset of grid power that would otherwise be consumed. These
emission factors were obtained from the most recent available EPA eGrid database (2007) [5].
Heat Recovery Offset
To obtain NOx emissions reductions associated with heat recovery, emission factors for NOX and CO2 were
obtained for small natural gas fired boilers (< 100 MMBtu/hr) from EPA's AP42 Table 1.4-1 (7/98). The factor for
NOx is 100 Ib/MMscf (the BOCES boilers do not have NOX control). The factor for CO2 is 120,000 Ib/MMscf.
Using aheating value of 1020 Btu/scf for natural gas results in emission factors of 0.1 Ib/MMBtu forNOx and
117.6 Ib/MMBtu for CO2 These emission factors were then applied to the average heat recovery for the Tecogen
Cogen array during the long term monitoring period to obtain annual emissions associated with the proportion of
baseline boiler operation offset by heat recovered from the Cogen array. This assumes that all of the heat recovered
from the Tecogen CHP array is utilized at BOCES. This is a reasonable assumption since the average heat
recovered from the CHP array during normal operations ( approx. 3 MMBtu/hr) is only 1.5 times higher than the
output rating of one of BOCES's five boilers (approx. 2 MMBtu/hr). The facility is easily capable of using all of
the recovered heat.
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2.0 VERIFICATION RESULTS
Test results are presented in the following subsections:
Section 2.1 - Electrical and Thermal Performance and Efficiency
Section 2.2 - Power Quality Performance
Section 2.3 - Emissions Performance
Section 2.4 - Emissions Reductions
2.1. ELECTRICAL AND THERMAL PERFORMANCE AND EFFICIENCY
2.1.1. Controlled Test Results
The heat and power production performance evaluation included electrical power output, heat recovery, and CHP
efficiency determinations during controlled test periods. Following the test runs, analysts reviewed the data and
determined that all test runs were valid by meeting the following criteria:
100 percent of the one-minute average power meter data were logged
data and log forms that show SUT operations conformed to the permissible variations throughout
the run (refer to Table 2-1)
ambient temperature and pressure readings were recorded at the beginning and end of the run
field data log forms were completed and signed
records demonstrate that all equipment met the allowable QA/QC criteria
Based on ASME PTC-17, the GVP-specified guidelines state that efficiency determinations were to be performed
within 60 minute test periods in which maximum variability in key operational parameters did not exceed specified
levels. Though the generic protocol recommends 1-hour test runs for internal combustion engines and 30-minute
test runs for microturbines, Southern has found that 30-minute test runs provide stable data with narrow confidence
intervals for both types of power plants. Therefore the controlled testing periods were planned to consist of three (3)
test runs, each 30 minutes long, at each power level (lOOkW, 75kW, and 50kW). The actual test runs were
somewhat shorter than planned (see section 3.1); however sufficient data were collected to characterize emissions
under each load condition.
Table 2-1 summarizes the maximum permissible variations observed in power output, ambient temperature, and
ambient pressure for each test run. The table shows that the PTC-17/GVP requirements for these parameters were
met for all test runs. Table 2-2 summarizes the ambient conditions during the controlled load tests.
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Table 2-1. Variability in Operating Conditions During Controlled Test Periods
Maximum
Allowable Variation
lOOkW
75 kW
50 kW
Runl
Run 2
Run 3
Runl
Run 2
Run 3
Runl
Run 2
Run 3
Maximum Observed Variation in Measured Parameters
Power Output (%
difference)3
±2%
-1.0
-1.7
-1.8
-1.0
0.4
-0.6
-1.4
-1.8
1.1
Ambient Temp. (°F)
±4°F
0.3
0.3
0.3
0.2
0.4
0.3
0.2
0.3
0.2
Ambient Pressure (%
difference)3
± 0.5 %
0.02
0.03
0.04
0.06
0.07
0.08
0.10
0.10
0.12
(Maximum - Minimum Value) / Average Value for Test Run * 100
Table 2-2. BOCES DG/CHP System Ambient
Conditions during Controlled Tests
Test ID
100 kW
75 kW
50 kW
Runl
Run 2
Run 3
Avg.
Runl
Run 2
Run 3
Avg.
Runl
Run 2
Run 3
Avg.
Run Average
Temp (°F)
59.6
59.0
58.6
59.1
57.6
57.2
56.6
57.1
56.0
55.6
Run Average
Pbar (psia)
14.6
14.6
14.6
14.6
14.6
14.6
14.6
14.6
14.6
14.6
Gross and net electrical performance and efficiency as measured during the controlled test period are presented in
Table 2-3. Net electrical performance is exclusive of power consumed by CHP system electrical loads required for
system operation (parasitic loads). Parasitic loads are disproportionally high during the controlled test period when
only one unit is operating as compared to normal operations when up to six cogeneration units may be operating.
Parasitic loads during the controlled test period averaged about 7 percent of gross power output, whereas during the
long term monitoring, parasitic loads averaged only 2-4 percent of gross power output (depending on load
conditions). Uncertainties given in table 1 were determined by measurement error propagation as detailed in
Section 7 of the GVP. The heat input determinations corresponding to the controlled test results are summarized in
Table 2-4.
Thermal performance as measured during the controlled test period is not reported. The thermal performance
measurements are not considered representative for several reasons. The heat recovery fluid flow measurement is
not considered reliable because the flow velocities with only a single unit operating were at or below the velocity at
which the instrument accuracy rapidly deteriorates. Heat losses with only a single unit operating are
disproportionately high compared to normal operations with up to six units operating. System controls, which seek
to maintain the return temperature to the cogeneration array at a constant level, did not appear to be able to operate
13
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May 2012
as intended with only a single unit operating, resulting in cycling of flow rate and return temperature. A detailed
assessment of these factors is provided in section 3.2.3 below.
Table 2-3. Controlled Test Electrical and Thermal Performance
Test ID
100
kW
75
kW
50
kW
Runl
Run 2
Run3
Avg.
+/-
Runl
Run 2
Run 3
Avg.
+/-
Runl
Run 2
Run3
Avg.
+/-
Heat Input
(MMBtu/h)
1.18
1.17
1.17
1.18
1.8%
0.85
0.85
0.86
0.86
1.8%
0.57
0.57
0.58
0.58
1.8%
Electrical Power Generation Performance
Net Power
Generated
(kW)
91.8
91.2
91.4
91.5
0.7%
66.2
66.1
66.5
66.3
0.7%
41.6
41.4
42.8
41.9
0.7%
Net
Electrical
Efficiency
(%)
26.5
26.6
26.6
26.6
3.0%
26.5
26.4
26.4
26.4
3.0%
24.7
24.6
25.2
24.8
3.0%
Gross
Power
Generated
(kW)
98.0
97.3
97.7
97.7
0.7%
72.3
72.3
72.6
72.4
0.7%
47.3
47.2
47.5
47.3
0.7%
Gross
Electrical
Efficiency
(%)
28.3
28.4
28.4
28.4
3.0%
28.9
28.9
28.8
28.9
3.0%
28.1
28.0
28.0
28.0
3.0%
Reported uncertainties by measurement error propagation per GVP in percentage
of reported value. Net electrical performance is exclusive of electrical loads
required for system operation (parasitic loads). Parasitic loads are
disproportionately high during the controlled test conditions as described above.
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May 2012
Table 2-4. Heat Input Determinations
Test ID
100 kW
75 kW
50 kW
Runl
Run 2
Run 3
Avg.
Runl
Run 2
Run 3
Avg.
Runl
Run 2
Run 3
Avg.
Fuel Input
Heat Input
(Btu/h)
1.2E+06
1.2E+06
1.2E+06
1.2E+06
8.5E+05
8.5E+05
8.6E+05
8.6E-KJ5
5.7E+05
5.7E+05
5.8E+05
5.8E-K)5
Gas Flow
Rate (scfli)
1303
1294
1295
1297
943
943
949
945
635
635
639
636
LHV
(Btu/scf)
905.5
905.5
905.5
a Reported LHV is the average of three fuel gas samples
collected on September 10, 2007
2.1.2. Long Term Test Results
Measurements necessary to determine electrical and thermal performance and efficiency were collected over a
period from September 2009 through September 2010. The heat recovery measurements account for heat made
available for facility operations, but do not reflect recovered heat energy actually used at the facility. However,
since the average heat recovered from the CHP array during full load operations ( approx. 3 MMBtu/hr) is only 1.5
times higher than the output rating of one of BOCES's five boilers (approx. 2 MMBtu/hr), the facility is easily
capable of using all of the recovered heat.
Table 2-6 provides a summary of the results. During normal operations at the BOCES facility, the cogeneration
array operates in response to electrical demand. As such, the array typically operates at nearly full load during
weekdays, with partial load at nights and on weekends. Full load conditions are characterized by power generation
rates over 300kW, and night/weekend conditions are characterized by generation rates less than 300 kW. The
cogeneration array operated nearly continuously throughout the year of monitoring, with only one brief period of
down time (43 hours) in late June 2010.
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May 2012
Table 2-5. Extended Test Results Summary
Annual
Average
Full Load -
(Weekday)
(>=300kW)
Partial Load -
(Night)
(<300kW)
Average
Net
Power
Output
(kW)
293
394
211
+/-
0.7%
0.7%
0.7%
Average
Heat
Recovery
(MMBtu/hr)
2.26
2.98
1.68
+/-
4.4%
4.4%
4.4%
Average
Thermal
Efficiency
(%)
53.7
60.4
48.2
+/-
4.9%
4.9%
4.9%
Average
Net
Electrical
Efficiency
(%)
23.5
25.8
21.3
+/-
3.0%
3.0%
3.0%
Average
Total
Efficiency
(%)
77.2
86.2
69.5
+/-
3.5%
3.5%
3.5%
Reported uncertainties by measurement error propagation per GVP.
Gross electrical efficiency during the extended test was 24.1 percent on an annual basis, 26.4 percent at full load
conditions, and 22 percent at partial load conditions. Parasitic loads accounted for 2 to 4 percent of power
production depending on load conditions. As can be seen in Table 3, the electrical and thermal efficiency of the
system is somewhat lower at partial load than at full load. The lower thermal efficiency at partial load may be due
to system heat losses - which amount to a greater proportion of the total heat recovered at partial load than at full
load.
The lower electrical efficiency at partial load is not fully explained by the data. However, at the very lowest loads
(occurring during weekend daytimes), fuel consumption was consistently observed to increase as power output
decreased. This could be due to the cogeneration array running in an inefficient operating range at the lowest load
conditions. During the controlled tests with only one of six units operating, electrical efficiency decreased slightly
at the 50 percent load condition, but not as much as was observed during extended monitoring of the full
cogeneration array.
2.2. POWER QUALITY PERFORMANCE
Power quality measurements planned for the controlled test period included frequency, power factor, and voltage
and current THD. During the controlled testing, a data logger malfunction corrupted the power quality data from
the power meter, so these data were not obtained. This is not considered to have a significant impact on the
verification, as power quality is proven to be acceptable for grid interconnection and use at the BOCES facility. A
utility will not allow grid interconnection if the power supplied is not of acceptable quality.
2.3. EMISSIONS PERFORMANCE
2.3.1. Emissions Test Results
Stack emission measurements were conducted during each of the controlled test periods in accordance with the
methods described above. Following the GVP, the SUT was maintained in a stable mode of operation during each
load condition based on PTC-17 variability criteria. Results are summarized in Table 2-6. Emissions results are
reported in units of parts per million volume for CO, CO2, THC, and NOX. Measured pollutant concentration data
were converted to mass emission rates using EPA Method 19 and are reported in units of pounds per hour (Ib/h).
The emission rates are also reported in units of pounds per kilowatt hour electrical output (Ib/kWh). They were
computed by dividing the mass emission rate by the electrical power generated during each test run.
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May 2012
Table 2-6. Tecogen Emissions During Controlled Test Periods
Test ID
lOOkW
75 kW
50 kW
Runl
Run 2
Run 3
Avg.
95% CI
Runl
Run 2
Run 3
Avg.
95% CI
Runl
Run 2
Run 3
Avg.
95% CI
Test ID
lOOkW
75 kW
50 kW
Runl
Run 2
Run 3
Avg.
95% CI
Runl
Run 2
Run 3
Avg.
95% CI
Runl
Run 2
Run 3
Avg.
95% CI
Gross Power
(kW)
98
97
98
98
72
72
73
72
47
47
48
47
Gross Power
(kW)
98
97
98
98
72
72
73
72
47
47
48
47
CO Emissions
ppm
175
162
168
168
1.7%
44
81
96
74
5.3%
not reported*
not reported*
not reported*
Ib/hr
0.17
0.16
0.16
0.17
0.04
0.08
0.09
0.07
0.06
0.08
0.09
0.08
Ib/MWh
1.8
1.6
1.7
1.7
0.5
1.1
1.2
0.9
1.4
1.7
1.8
1.6
THC Emissions
ppm
5.7
4.8
4.9
5.1
1.2%
8.8
8.5
8.7
5.8
2.3%
273
288
292
284
1.5%
Ib/hr
0.006
0.005
0.005
0.005
0.008
0.008
0.008
0.008
0.154
0.185
0.201
0.180
Ib/MWh
0.06
0.05
0.05
0.05
0.11
0.11
0.11
0.11
3.2
3.9
4.2
3.8
CO2 Emissions
Volume %
9.3
9.2
9.2
9.2
0.02%
9.1
9.1
9.1
9.1
0.06%
9.2
9.2
9.2
9.2
0.07%
Ib/hr
91
90
91
91
80
85
86
84
52
59
63
58
Ib/MWh
930
927
928
928
1113
1182
1180
1158
1095
1250
1328
1224
NOx Emissions
ppm
12.8
12.9
13.1
12.9
2.5%
8.4
8.3
7.8
5.6
4.0%
843
881
881
869
1.6%
Ib/hr
0.013
0.013
0.013
0.013
0.007
0.008
0.007
0.008
0.475
0.567
0.608
0.550
Ib/MWh
0.1
0.1
0.1
0.1
0.1
0.1
0.1
0.1
10.0
12.0
12.8
11.6
*Carbon monoxide results for the 50 percent load condition are not reported because the instrument failed the span drift check
at the conclusion of the testing at this condition and the results appeared suspect upon examination (concentrations during the
run were frequently recorded as negative values).
THC and NOX emissions at the 50kW load condition are elevated. This is due to poor engine performance at partial
load - an abnormal operating condition. In normal operations, the units are run at greater than 60 percent load and
individual units are taken on and offline in response to facility electrical demand.
Uncertainties given in this table were determined by calculating a 95 percent confidence interval over the mean of
all three runs at each load condition. The higher uncertainty for CO emissions at the 75kW load condition is due to
a a greater degree of fluctuation in CO concentration observed at the lower load conditions.
17
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2.4. ESTIMATION OF ANNUAL NOX AND CO2 EMISSION REDUCTIONS
SRI/USEPA-GHG-VR-45 vl.6
May 2012
The approach for estimating the annual emission reductions that may result from use of the Tecogen CHP units at
this facility was outlined above (section 1.3.6). The Tecogen emissions were compared to both the New York State
and national power system average emissions as published in EPA's eGRID database. The results of this analysis
are given in Table 2-7 below.
Table 2-7. Estimation of Emission Reductions at BOCES
Regional
Power
System
Scenarios
New
York
State
National
Annual SUT
Emissions"
(tpy)
NOX
0.1554
0.1554
C02
1121
1121
Baseline Case Annual Emissions (tpy)
Avoided Grid
Emissions1"
NOX
1.07
2.34
C02
1000
1604
Boiler Emissions Offset0
NOX
0.92
0.92
C02
1104
1104
Total Baseline
Emissions
NOX
1.99
3.26
C02
2103
2708
Estii
An
Emi
Red 11
(t
NOX
1.83
3.10
nated
nual
ssion
ctions
py)
C02
983
1588
a Based on the SUT's performance during the verification period, an expected availability of 95 percent, and the average
measured power output for the full cogen array.
b From eGRID 2007
c From AP42 Table 1.4-1
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3.0 DATA QUALITY ASSESSMENT
During the unusually long period of time between approval of the TQAP for this verification and commencement of
field work, a number of minor changes to the test plan became necessary due to personnel and instrumentation
changes. These changes were documented in a memorandum dated 9/7 2009, before the beginning of field
measurement activity. The impact on data quality of all of the changes is assessed in this memorandum. None of
the changes were found to have any negative effect on data quality.
3.1. DATA QUALITY OBJECTIVES
Under the ETV program, the GHG Center specifies DQOs for each verification parameter before testing
commences as a statement of data quality. The DQOs for this verification were developed based on past DG/CHP
verifications conducted by the GHG Center, input from EPA's ETV QA reviewers, and input from both the GHG
Centers' executive stakeholders groups and industry advisory committees. As such, test results meeting the DQOs
will provide an acceptable level of data quality for technology users and decision makers. The DQOs for electrical
and CHP performance are quantitative, as determined using a series of measurement quality objectives (MQOs) for
each of the measurements that contribute to the parameter determination:
Verification Parameter DQO (relative uncertainty)
Electrical Performance ±0.7 %
Electrical Efficiency ±3.0%
CHP Thermal Efficiency ±4.9 %
Each test measurement that contributes to the determination of a verification parameter has stated MQOs, which, if
met, demonstrate achievement of that parameter's DQO. This verification is based on the GVP which contains
MQOs including instrument calibrations, QA/QC specifications, and QC checks for each measurement used to
support the verification parameters being evaluated. Details regarding the measurement MQOs are provided in the
following sections of the GVP:
Electrical Performance Data Validation
Electrical Efficiency Data Validation
CHP Performance Data Validation
The DQO for emissions is qualitative in that the verification will produce emission rate data that satisfies the QC
requirements contained in the EPA Reference Methods specified for each pollutant. Details regarding the
measurement MQOs for emissions are provided in the following section of the GVP:
§8.4 Emissions Data Validation
Controlled Test Data Capture
Completeness goals for this verification were to obtain valid data for 90 percent of the test periods (controlled test
period and extended monitoring).
For the controlled test period, three 30-minute test runs were planned at each load condition, or a total of 90
minutes data collection at each load condition. Due to time constraints imposed by site operations (the testing had
to be completed at night), this goal was revised in the field as 60 minutes data collection at each load condition. A
total of 59 minutes data were collected at both the lOOkW and 75kW loads. The 50kW load test was cut short at 39
minutes as normal facility operations were due to re-start. Thus, the completeness goal for controlled test data
collection was not met. However, examination of the data clearly shows that sufficient emissions and electrical and
thermal efficiency results were obtained at each load condition to adequately characterize operations. Therefore,
the impact on data quality of this goal not being met is considered insignificant.
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Some of the emissions measurements were not recorded by the PEMS, or were deemed invalid upon inspection of
the data and QC checks. For the lOOkW runs, only 64% of the THC data were valid. For the 75kW runs, only 46%
of the CO data, 62% of the THC data and 80% of the NOx data were valid. For the 50kW runs, only 22% of the
CO data were valid. All other data met the 90% valid data capture goal. Careful examination of the data shows
that sufficient data were captured to adequately characterize emissions at each load condition, except that the
average CO results for the 50kW runs cannot be considered fully representative as negative values were recorded
and the analyzer failed a drift check at the conclusion of the run. The impact on overall data quality of this is small,
however, since CHP unit operations at the 50kW load condition are not representative of normal operations.
Long Term Test Data Capture
The RTDs installed on the supply and return sides of the CHP heat recovery loop for long term monitoring proved
unreliable and failed to provide useful data after the end of November 2009. Valid data were obtained from these
sensors for approximately two months from 9/23/2009-11/25/2009 excepting a period from 11/2-13/2009. To
address this, Southern obtained supply and return temperature and flow data from the BBS building management
system that was archived commencing on 11/7/2009 and extending through 9/30/2010. The BBS data were
examined and compared with an overlapping period of Southern's data from November 17-24 2009 and compare
reasonably well (average percent difference between delta_T from CDH and BBS data is on the order of 10%).
Long term results based on the BBS sensors are considered acceptable. Thus, valid long term thermal efficiency
data were obtained for the period from 9/23/2009 through 9/20/2010. Power output and fuel consumption data
collection ceased on 8/31/2010. Thus, valid electrical efficiency data were collected starting 9/10/2009 and
extending through 8/31/2010.
3.2. DOCUMENTATION OF MEASUREMENT QUALITY OBJECTIVES
The field team leader reviewed collected data for reasonableness and completeness while in the field. The field
team leader also reviewed data from each of the controlled test periods to verify that variability criteria specified
below (see Table 2-1) were met. The emissions testing data were validated by reviewing instrument and system
calibration data and ensuring that those and other reference method criteria were met. Calibrations for fuel flow,
pressure, temperature, electrical and thermal power output, and ambient monitoring instrumentation were reviewed
on site to validate instrument functionality. Other data such as fuel LHV analysis results were reviewed, verified,
and validated after testing had ended. All collected data was classified as either valid, suspect, or invalid upon
review, using the QA/QC criteria specified in the TQAP. Review criteria are in the form of factory and on-site
calibrations, maximum calibration and other errors, audit gas analyses, and lab repeatability. Results presented here
are based on measurements which met the specified data quality objectives (DQOs) and QC checks, and were
validated by the GHG Center.
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May 2012
3.2.1. Electrical Generation Performance
Table 3-1 summarizes the MQOs for electrical generation performance.
Table 3-1. Electrical Generation Performance MQOs
Measurement
kW, kVA,
kVAR, PF, I,
V, f(Hz), THD
V, I
Ambient
temperature
Barometric
pressure
QA/QC Check
Power meter
National Institute of
Standards and
Technology (NIST)
traceable calibration
CT documentation
Sensor function
checks
Power meter
crosschecks
NIST-traceable
calibration
Ice and hot water
bath crosschecks
NIST-traceable
calibration
When Performed
18-month period
At purchase
Beginning of load
tests
Before field testing
18-month period
Before and after field
testing
18-month period
Allowable Result
± 2.0%
ANSI Metering
Class 0.3%; ±1.0%
to 360 Hz (6th
harmonic)
V: ± 2%
I: ± 3%
±0.1% differential
between meters
±1°F
Ice water: ± 0.6 °F
Hot water: ±1. 2 °F
±0.1"Hgor±0.05
psia
Result Achieved
Meets spec.
Meets spec.
Meets spec.
Meets spec.
Meets spec.
Meets spec.
Meets spec.
All of the MQOs met the performance criteria. Following the GVP, the MQO criteria demonstrate that the DQO of
±1% relative uncertainty for electrical performance was met.
3.2.2. Electrical Efficiency Performance
Table 3-2 summarizes the MQOs for electrical efficiency performance.
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May 2012
Table 3-2. Electrical Efficiency MQOs
Measurement
Gas meter
Gas pressure
Gas temperature
Fuel Gas LHV
QA/QC Check
NIST-traceable calibration
Differential pressure check
NIST-traceable calibration
Crosscheck with ambient
pressure sensor
NIST-traceable calibration
Ice and hot water bath
crosschecks
NIST-traceable standard
gas calibration
ASTMD 1945 duplicate
sample analysis and
repeatability
When
Performed
18-month period
Prior to testing
18-month period
Before and after
field testing
18-month period
Before field testing
Weekly
Each sample
Allowable Result
± 1.0% of reading
<0.1"
±0.5%ofFS
± 0.08 psia
differential between
sensors
± 1.0%ofFS
Ice water: ± 0.6 °F
Hot water: ± 1.2°F
+ 1.0% of reading
Within D 1945
repeatability limits for
each gas component
Result Achieved
meets spec.
Meets spec.
Meets spec.
Meets spec.
Meets spec.
Meets spec.
Meets spec.
Meets spec.
Following the GVP, the MQO criteria in Tables 3-1 and 3-2 demonstrate that the DQO of ±3.0 % relative
uncertainty for electrical efficiency was met.
3.2.3. CHP Thermal Efficiency Performance
Table 3-3 summarizes the MQOs for CHP thermal efficiency performance.
Table 3-3. CHP Thermal Efficiency MQOs
Description
Flow
Tsuppiy and
Tretum sensors
QA/QC Check
Sensor function
checks
NIST-traceable
calibration
Ice and hot water
bath crosschecks
When Performed
At installation
18-month period
Before field testing
Allowable Result
Passes mfg. function
checks and sensor to
data loop check
± 0.6 °F between 100
and 2 10 °F
Ice water: ± 0.6 °F
Hot water: ± 1.2°F
Result Achieved
Meets spec.
Meets spec.
Meets spec.
All of the MQOs met the performance criteria. Following the GVP, the MQO criteria in Tables 3-1, 3-2, and 3-3
demonstrate that the DQO of ±4.9 % relative uncertainty for CHP thermal efficiency was met.
The thermal performance measurements for the controlled test period are not considered representative for several
reasons and are not reported. An assessment of the results and test configuration leading to this conclusion is given
in the following paragraphs.
The heat recovery fluid flow measurement is not considered reliable because the flow velocities with only a single
unit operating were at or below the velocity at which the instrument accuracy rapidly deteriorates. The fluid
velocity at the nominal flow rate with only a single unit operating (40 gpm in a 4 inch pipe) is about 1 foot per
second. This is at the lower limit at which the Controlatron ultrasonic meter used during the controlled tests may be
considered to provide acceptably accurate results. At velocities lower that 1 foot per second, the accuracy of the
instrument deteriorates rapidly.
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System controls, which seek to maintain the return temperature to the cogeneration array at a constant level, did not
appear to be able to operate as intended with only a single unit operating, resulting in cycling of flow rate and
return temperature. This is illustrated in Figure 2-1. The cause of this cycling has been exhaustively investigated
but cannot be determined with certainty from the data available. Data from the building management system was
sought in an attempt to determine cause, but was not available. Building data archives started in November 2009.
The system controls seek to keep the return temperature constant. It is hypothesized that at the low heat recovery
fluid flows associated with operation of only one of the six CHP units, the controls were not able to stabilize the
return temperature, resulting in the cyclic behavior observed.
Figure 3-1: Periodic Variation in Controlled Test Heat Recovery Data
250
200
£ 15°
u
i
Q.
100
50
-- 45
-- 35
30
50
40
Q.
+ 25-2
1
u.
20
-- 15
10
-- 5
0:00
0:28
0:57
1:26 1:55 2:24 2:52
Time on September 10, 2009
3:21
3:50
4:19
T_supply(F) T_return (F)
Flow (gpm)
Finally, heat losses with only a single unit operating are disproportionately high compared to normal operations
with up to six units operating.
3.2.4. Emissions Measurement MQOs
Sampling system QA/QC checks were conducted in accordance with GVP and TQAP specifications to ensure the
collection of adequate and accurate emissions data. The reference methods specify detailed sampling methods,
apparatus, calibrations, and data quality checks. The procedures ensure the quantification of run-specific
instrument and sampling errors and that runs are repeated if the specific performance goals are not met. Table 3-4
summarizes relevant QA/QC procedures.
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May 2012
Table 3-4. Summary of Emissions Testing Calibrations and QA/QC Checks
Description
CO, CO2,O2
NOX
THC
Ambient
temperature
Barometric
pressure
QA/QC Check
System zero drift test
System span drift test
System zero drift test
System span drift test
System zero drift test
System span drift test
Temperature within
allowable range
Barometric pressure within
allowable range
When Performed
After each test run
After each test run
After each test run
After each test run
After each test run
After each test run
After each test run
After each test run
Allowable Result
± 2% of analyzer
span
±4% of analyzer
span
± 2% of analyzer
span
±4% of analyzer
span
±2% of analyzer
span
±4% of analyzer
span
Within ±10°F
Within ±l"Hg
Result Achieved
All calibrations,
system bias checks,
and drift tests were
within the allowable
criteria except that
the CO measurement
failed the span drift
check for the 50
percent load
condition.
All criteria were met
fortheNOx
measurement
system.
All criteria were met
for the THC
measurement
system.
Within the allowable
criteria
Within the allowable
criteria
Satisfaction and documentation of each of the calibrations and QC checks verified the accuracy and integrity of the
measurements and that reference method criteria were met for each of the parameters.
3.3. AUDITS
An independent Technical Systems Audit was conducted during the controlled test period on September 10, 2009
by David A. Gratson of Neptune and Company, Inc. and Robert S. Wright, Quality Assurance Manager, Air
Pollution Prevention and Control Division, NRMRL EPA. An audit report was received September 15, 2009. The
auditors main findings were (1) that the ultrasonic flow meter used during the controlled tests may not give reliable
readings due to low flow and possible lack of turbulence and (2) that the heat transfer fluid samples showed some
discoloration and may not have been solely water. Examination of the data showed that the lowest heat recovery
fluid velocities recorded were near the low end of the ultrasonic meter's range. Based on this, and other factors,
thermal efficiency was not reported for the controlled test (see section 3.2.3). Southern confirmed with BES that
the heat recovery fluid is water.
Southern's QA manager also conducted an audit of data quality. This consisted of verifying computations and
traceability from the raw data collected through final results reported and verifying that all required QA/QC checks
were conducted and documented. The audit found the results to be of acceptable quality.
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SRI/USEPA-GHG-VR-45 vl.6
May 2012
4.0 REFERENCES
[1] Southern Research Institute, Test and Quality Assurance Plan - Building Energy Solutions, LLP
Tecogen DG / CHP Installation SRI/USEPA-GHG-QAP-45, www.sri-rtp.com, Greenhouse Gas
Technology Center, Southern Research Institute, Durham, NC, January 2008.
[2] Association of State Energy Research and Technology Transfer Institutions, Distributed
Generation and Combined Heat and Power Field Testing Protocol, DG/CHP Version,
www.dgdata.org/pdfs/field_protocol.pdf, ASERTTI, Madison, WI, October 2004.
[3] Southern Research Institute, Generic Verification Protocol - Distributed Generation and
Combined Heat and Power Field Testing Protocol, SRI/USEPA-GHG-GVP-04, www.sri-
rtp.com, Greenhouse Gas Technology Center, Southern Research Institute, Research Triangle
Park, NC. July 2005.
[4] CRC Handbook of Chemistry and Physics. Robert C. Weast, Ph.D., editor, CRC Press, Inc., Boca
Raton, FL. 1980.
[5] U.S. Environmental Protection Agency, Emissions & Generation Resource Integrated Database
(eGRID) Version 2.01, available from
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