HomeMy WebLinkAboutClarks Point Feasibility Assessment for Biomass Heating Systems 07-26-2013-BIO
Feasibility Assessment for Biomass Heating Systems
Clark’s Point, Alaska
800 F Street, Anchorage, AK 99501
p (907) 276-6664 f (907) 276-5042
Tony SlatonBarker, PE,
Lee Bolling, CEA, and
David Nicolai, PE
FINAL REPORT - 7/26/2013
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc. i
Contents
I. Executive Summary ............................................................................................................ 1
II. Introduction ...................................................................................................................... 3
III. Preliminary Site Investigation – Community Center ........................................................... 4
BUILDING DESCRIPTION ................................................................................................................................................... 4
EXISTING HEATING SYSTEM .............................................................................................................................................. 4
DOMESTIC HOT WATER................................................................................................................................................... 4
BUILDING ENVELOPE ....................................................................................................................................................... 4
AVAILABLE SPACE ........................................................................................................................................................... 4
STREET ACCESS AND FUEL STORAGE ................................................................................................................................... 5
BUILDING OR SITE CONSTRAINTS ....................................................................................................................................... 5
BIOMASS SYSTEM INTEGRATION ........................................................................................................................................ 5
BIOMASS SYSTEM OPTIONS .............................................................................................................................................. 5
IV. Preliminary Site Investigation – CPVC Office ..................................................................... 6
BUILDING DESCRIPTION ................................................................................................................................................... 6
EXISTING HEATING SYSTEM .............................................................................................................................................. 6
DOMESTIC HOT WATER................................................................................................................................................... 6
BUILDING ENVELOPE ....................................................................................................................................................... 6
AVAILABLE SPACE ........................................................................................................................................................... 6
STREET ACCESS AND FUEL STORAGE ................................................................................................................................... 6
BUILDING OR SITE CONSTRAINTS ....................................................................................................................................... 6
BIOMASS SYSTEM INTEGRATION ........................................................................................................................................ 7
BIOMASS SYSTEM OPTIONS .............................................................................................................................................. 7
V. Preliminary Site Investigation – Water Treatment Plant ..................................................... 8
BUILDING DESCRIPTION ................................................................................................................................................... 8
EXISTING HEATING SYSTEM .............................................................................................................................................. 8
DOMESTIC HOT WATER................................................................................................................................................... 8
BUILDING ENVELOPE ....................................................................................................................................................... 8
AVAILABLE SPACE ........................................................................................................................................................... 8
STREET ACCESS AND FUEL STORAGE ................................................................................................................................... 8
BUILDING OR SITE CONSTRAINTS ....................................................................................................................................... 8
BIOMASS SYSTEM INTEGRATION ........................................................................................................................................ 8
BIOMASS SYSTEM OPTIONS .............................................................................................................................................. 9
VI. Preliminary Site Investigation – City Office ...................................................................... 10
BUILDING DESCRIPTION ................................................................................................................................................. 10
EXISTING HEATING SYSTEM ............................................................................................................................................ 10
DOMESTIC HOT WATER................................................................................................................................................. 10
BUILDING ENVELOPE ..................................................................................................................................................... 10
AVAILABLE SPACE ......................................................................................................................................................... 10
STREET ACCESS AND FUEL STORAGE ................................................................................................................................. 10
BUILDING OR SITE CONSTRAINTS ..................................................................................................................................... 10
BIOMASS SYSTEM INTEGRATION ...................................................................................................................................... 11
BIOMASS SYSTEM OPTIONS ............................................................................................................................................ 11
VII. Preliminary Site Investigation – Clinic ............................................................................ 12
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc. ii
BUILDING DESCRIPTION ................................................................................................................................................. 12
EXISTING HEATING SYSTEM ............................................................................................................................................ 12
DOMESTIC HOT WATER................................................................................................................................................. 12
BUILDING ENVELOPE ..................................................................................................................................................... 12
AVAILABLE SPACE ......................................................................................................................................................... 12
STREET ACCESS AND FUEL STORAGE ................................................................................................................................. 12
BUILDING OR SITE CONSTRAINTS ..................................................................................................................................... 12
BIOMASS SYSTEM INTEGRATION ...................................................................................................................................... 13
BIOMASS SYSTEM OPTIONS ............................................................................................................................................ 13
VIII. Preliminary Site Investigation – Post Office ................................................................... 14
BUILDING DESCRIPTION ................................................................................................................................................. 14
EXISTING HEATING SYSTEM ............................................................................................................................................ 14
DOMESTIC HOT WATER................................................................................................................................................. 14
BUILDING ENVELOPE ..................................................................................................................................................... 14
AVAILABLE SPACE ......................................................................................................................................................... 14
STREET ACCESS AND FUEL STORAGE ................................................................................................................................. 14
BUILDING OR SITE CONSTRAINTS ..................................................................................................................................... 15
BIOMASS SYSTEM INTEGRATION ...................................................................................................................................... 15
BIOMASS SYSTEM OPTIONS ............................................................................................................................................ 15
IX. Energy Consumption and Costs ....................................................................................... 16
WOOD ENERGY ........................................................................................................................................................... 16
ENERGY COSTS ............................................................................................................................................................ 16
EXISTING FUEL OIL CONSUMPTION .................................................................................................................................. 17
BIOMASS SYSTEM CONSUMPTION ................................................................................................................................... 18
X. Preliminary Cost Estimating ............................................................................................. 20
XI. Economic Analysis .......................................................................................................... 22
O&M COSTS .............................................................................................................................................................. 22
DEFINITIONS................................................................................................................................................................ 22
RESULTS ..................................................................................................................................................................... 24
SENSITIVITY ANALYSIS ................................................................................................................................................... 25
XII. Forest Resource and Fuel Availability Assessments ........................................................ 26
FOREST RESOURCE ASSESSMENTS .................................................................................................................................... 26
AIR QUALITY PERMITTING .............................................................................................................................................. 26
XIII. General Biomass Technology Information ..................................................................... 28
HEATING WITH WOOD FUEL ........................................................................................................................................... 28
TYPES OF WOOD FUEL .................................................................................................................................................. 28
HIGH EFFICIENCY CORD WOOD BOILERS ........................................................................................................................... 29
LOW EFFICIENCY CORD WOOD BOILERS ........................................................................................................................... 29
HIGH EFFICIENCY WOOD STOVES .................................................................................................................................... 30
BULK FUEL BOILERS ...................................................................................................................................................... 30
GRANTS ..................................................................................................................................................................... 30
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc. iii
Appendices
Appendix A – Site Photos
Appendix B – Economic Analysis Spreadsheet
Appendix C – Site Plan
Appendix D – AWEDTG Field Data Sheet
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc. iv
Abbreviations
ACF Accumulated Cash Flow
ASHRAE American Society of Heating, Refrigeration, and Air-Conditioning Engineers
AEA Alaska Energy Authority
AFUE Annual Fuel Utilization Efficiency
AHU Air Handling Unit
ARCH Architectural
B/C Benefit / Cost Ratio
BAS Building Automation System
BTU British Thermal Unit
BTUH BTU per hour
CCF One Hundred Cubic Feet
CEI Coffman Engineers, Inc.
CFM Cubic Feet per Minute
CIRC Circulation
CMU Concrete Masonry Unit
CPVC Clark’s Point Village Council
CRAC Computer Room Air Conditioning
CWCO Cold Weather Cut Out
DDC Direct Digital Control
∆T Delta T (Temperature Differential)
ECI Energy Cost Index
ECM Energy Conservation Measure
EF Exhaust Fan
Eff Efficiency
ELEC Electrical
EPDM Ethylene Propylene Diene Monomer
EUI Energy Utilization Index
F Fahrenheit
ft Feet
GPM Gallons Per Minute
HP Horsepower
HPS High Pressure Sodium
HVAC Heating, Ventilating, and Air-Conditioning
IESNA Illuminating Engineering Society of North America
in Inch(es)
IPLC Integrated Power and Load Circuit
IRC Internal Revenue Code
kBTU One Thousand BTUs
kWh Kilowatt-Hour
LED Light-Emitting Diode
MBH Thousand BTUs per Hour
MECH Mechanical
MH Metal Halide
O&M Operations and Maintenance
MMBTU One Million BTUs
P Pump
PC Project Cost
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc. v
PF Power Factor
R R-Value
PH Phase
SC Shading Coefficient
SAT Supply Air Temperature
SF Square Feet, Supply Fan
TEMP Temperature
U U-Value
V Volts
VFD Variable Frequency Drive
W Watts
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc. vi
List of Figures
Fig. 1 – Clark’s Point, Alaska – Google Maps ................................................................................................. 3
Fig. 2 – Clark’s Point Upper and Lower Village – USGS ................................................................................. 3
List of Tables
Table 1.0 – Economic Analysis Results .......................................................................................................... 1
Table 1.1 – Economic Analysis Results - Continued ...................................................................................... 2
Table 2 – Energy Comparison ..................................................................................................................... 17
Table 3 – Existing Fuel Oil Consumption ..................................................................................................... 17
Table 4 – High Efficiency Wood Stove Fuel Consumption .......................................................................... 18
Table 5 – High Efficiency Wood Boiler Fuel Consumption .......................................................................... 19
Table 6 – Estimate of Probable Costs for one High Efficiency Wood Stove in Clark’s Point....................... 20
Table 7 – Estimate of Probable Costs for Tarm Solo Plus 30 or 40 in Clark’s Point .................................... 21
Table 8 – Inflation rates .............................................................................................................................. 22
Table 9 – Economic Definitions ................................................................................................................... 23
Table 10 – Economic Analysis Results ......................................................................................................... 24
Table 11 – Economic Analysis Results - Continued ..................................................................................... 25
Table 12 – Water Treatment Plant and Clinic Analysis ............................................................................... 25
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc. 1
I. Executive Summary
A preliminary feasibility assessment was completed to determine the technical and economic viability of
biomass heating systems at five buildings in Clark’s Point, Alaska. In the study, the proposed biomass
system determined to be the most practical and cost effective for the Community Center, CPVC Office
and City Office are high efficiency wood stoves. The proposed biomass system for the Water Treatment
Plant and Clinic are Tarm Solo Plus wood boilers, located in an addition to each building.
The results of the economic evaluation for all five buildings are shown below. It was found that
installing high efficiency wood stoves would be typically considered economically justified, due to the
fact that the benefit to cost ratio of each project is greater than 1.0. However, installing the Tarm Solo
Plus wood boilers would not be typically considered economically justified because the benefit to cost
ratios are less than 1.0.
Economic Analysis Results
Building
Community
Center CPVC Office Water
Treatment Plant
Proposed Biomass System
Two Blaze King
Classic High
Efficiency Wood
Stoves
One Blaze King
Classic High
Efficiency
Wood Stove
Tarm Solo Plus
40 Wood Boiler
Project Capital Cost ($25,774) ($12,887) ($193,754)
Simple Payback 4.3 years 4.3 years 46.3 years
Present Value of Project Benefits (20 year life) $562,880 $281,440 $281,440
Present Value of Operating Costs (20 year life) ($397,122) ($198,732) ($149,444)
Benefit / Cost Ratio of Project (20 year life) 6.43 6.42 0.68
Net Present Value (20 year life) $139,984 $69,821 ($61,758)
Year Accumulated Cash Flow is Net Positive First Year First Year First Year
Year Accumulated Cash Flow > Project Capital
Cost
3.9 years 3.9 years >20 years
Table 1.0 – Economic Analysis Results
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc. 2
Economic Analysis Results
Building City Office Clinic
Proposed Biomass System
One Blaze King Classic
High Efficiency Wood
Stove
Tarm Solo Plus 30 Wood
Boiler
Project Capital Cost ($12,887) ($193,754)
Simple Payback 5.9 years 46.3 years
Present Value of Project Benefits (20 year life) $211,080 $281,440
Present Value of Operating Costs (20 year life) ($149,455) ($149,444)
Benefit / Cost Ratio of Project (20 year life) 4.78 0.68
Net Present Value (20 year life) $48,738 ($61,758)
Year Accumulated Cash Flow is Net Positive First Year First Year
Year Accumulated Cash Flow > Project Capital
Cost
5.0 years >20 years
Table 1.1 – Economic Analysis Results - Continued
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc. 3
II. Introduction
A preliminary feasibility assessment was completed to determine the technical and economic viability of
biomass heating systems for five buildings in Clark’s Point, AK. The study buildings include: 1) Council
Community Center, 2) Clark’s Point Village Council (CPVC) Office, 3) Water Treatment Plant, 4) City
Office, and 6) Clinic. The first two buildings are located in the lower village and the remaining buildings
are located in the upper village. The locations are shown in Figures 1 and 2.
Fig. 1 – Clark’s Point, Alaska – Google Maps
Fig. 2 – Clark’s Point Upper and Lower Village – USGS
Lower Village
Upper Village
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc. 4
III. Preliminary Site Investigation – Community Center
Building Description
The Clark’s Point Village Council Community Center is a 4,000 SF two story building, built in 1946. It has
seen a variety of uses throughout its life. Currently, half of the upper floor is used as a community
gathering place, approximately twice a month. The rest of the building is used as itinerant housing for
commercial fishing crews in the summer, and is unheated and unoccupied the rest of the year. Its use
during the winter is approximately 8 hours a month, and during the summer, it is used continuously. No
energy audit has been conducted at the building.
Existing Heating System
Two heating systems are present in the building. The central boiler and existing baseboard heating is
abandoned in place since the boiler system has corroded to the point where it is unusable in any form or
function.
Toyo/Monitor oil-fired space heaters are present in general areas throughout the building to provide
space heating. During the summer, the tenants operate the heaters as desired, but only the one in the
Community Center Gathering Room is used throughout the winter. It is only used to warm up the space
prior to a meeting, and otherwise the space is unheated.
A Toyostove Laser 73 (40,000 Btu/hr output) is located in Gathering Room. And there are three Monitor
M-441 stoves (43,000 Btu/hr output) distributed throughout the rest of the building.
There is a large, abandoned in place, fuel tank outside the building behind the boiler room, which served
the old boiler system. There are 55-gallon fuel tanks outside the wall for each Toyo/Monitor heater. Fuel
is used for heating only.
Domestic Hot Water
Domestic hot water is provided with a 30-gallon electric water heater; however it is only in use in the
summer. The building is drained and winterized through the off season to prevent damage to the
plumbing system.
Building Envelope
The walls of the building are 2x4 wood stud construction that are estimated to have R-15 fiberglass batt
insulation. The roof is a cold roof with a vented attic space, with an unknown amount and type of
insulation because it could not be accessed. It is estimated that the roof insulation is R-19 fiberglass batt
insulation. Most of the windows are double pane; however, 3 older windows left in the building are
single pane.
Available Space
There is space inside the building for multiple residential style wood stoves, near each of the
Toyo/Monitor stoves. However, an addition, modular boiler system, or new building would be needed
to house any larger wood boiler type systems.
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
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Street Access and Fuel Storage
The building is situated along a gravel road and a truck can easily access the front and sides of the
building. There is adequate space around the building for a wood storage shed and/or wood boiler
building. Brush may have to be removed and additional gravel may be necessary to situate any new
structures.
Building or Site constraints
The site is flat, however, significant spring snowmelt pooling was observed throughout the area. Any
new buildings or additions for a boiler system or wood sheds would need to be located on an elevated
pad or on pile foundations to account for the wet site conditions.
Biomass System Integration
The building’s abandoned hydronic system is in a serious state of disrepair and would require significant
renovations to be brought into service. Installing a wood boiler system to integrate into this abandoned
hydronic system would require significant costs. However, high efficiency wood stoves, used similar to
the Toyo/Monitor stoves would be easily achievable.
Biomass System Options
There are two options for incorporating biomass systems into the Community Center:
1) Two high efficiency wood stoves, or
2) A high efficiency wood boiler system in a detached building.
Both systems would require a person to load and fire the wood heating systems by hand.
Two high efficiency wood stoves would be the cheapest and lowest tech option. The wood stoves would
be easy to operate and would require minimal maintenance compared to a wood boiler system. The
wood stoves would be used to provide a base heat load for the building during occupied times.
Occupants would fire the stoves regularly to provide as much heating oil displacement as they wish. The
Toyo/Monitor stove would still be used to make up for additional required heating during occupied
times and as heaters when the building is unoccupied. For this study, two Blaze King Classic high
efficiency wood stoves, each with an output of 48,065 BTU/hr for 12 hours, were selected as the
proposed biomass system to evaluate.
The second option is a wood fired boiler system, which will be more expensive and require more
maintenance than a wood stove. A wood fired boiler can be loaded and fired in batches, which heats up
a large volume of water for space heating. This allows a wood fired boiler to be loaded less times
throughout the day than a wood stove, which would need a higher loading frequency. The wood fired
boiler system would be located in a detached boiler building or addition and heating pipes would be
routed to the building. Pre-insulated heat pipes are typically installed below grade if it is in detached
building a significant distance from heat load. However, due to the significant expense of integrating
into the building’s abandoned hydronic system, or installing a new hydronic system, and due to the fact
that the building is regularly allowed to go cold during the winter, this option is not practical and was
not evaluated in this study.
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc. 6
IV. Preliminary Site Investigation – CPVC Office
Building Description
The CPVC Office is a 1,200 SF, one story building, constructed around 1948. It is used as office space for
the Clark’s Point Village Council and also itinerant federal officials in Clark’s Point as part of the summer
fishing season. It has a large main room and two smaller ancillary rooms. The building has not had an
energy audit. It is used 30 to 40 hours per week by up to 4 people.
Existing Heating System
The CPVC Office building is heated by a single Toyo stove located in the main room. There is no boiler or
boiler room. The stove is a Toyo Laser 56, direct vented heating oil furnace with an output of 22,000
Btu/hr. The unit has its own controls and thermostat. Maintenance is performed as required to keep the
unit operating, and it appears to be in good working order. The age of the unit is unknown. One 55 gal
heating oil tank is located adjacent the exterior wall near the stove. The tank is elevated and supported
by a wooden brace off of the wall. No spill containment is present around the tank and fuel in the tank is
only used for heating.
Domestic Hot Water
No running water system is present in the building.
Building Envelope
The walls of the building are 2x4 wood stud construction that are estimated to have R-15 fiberglass batt
insulation. The roof is a cold roof with a vented attic space, with an unknown amount and type of
insulation because it could not be accessed. It is estimated that the roof insulation is R-19 fiberglass batt
insulation. The windows are all double pane windows. There is an unheated arctic entry for the main
entrance.
Available Space
There is space inside the building for a residential style high efficiency wood stove. There is no space for
a wood boiler system in the building.
Street Access and Fuel Storage
The building is situated along a gravel road and a truck can easily access the front and sides of the
building. There is adequate space around the building for a wood storage shed. Brush may have to be
removed and additional gravel may be necessary to properly install the new structure.
Building or Site constraints
The site is flat, however, significant spring snowmelt pooling was observed throughout the area. Any
new buildings or additions for a boiler system or wood sheds would need to be located on an elevated
pad or on pile foundations to account for the wet site conditions.
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc. 7
Biomass System Integration
There currently is no hydronic system present in the building. Retrofitting the building to utilize a
hydronic system would require significant renovations to route the piping and provide an adequate
hydronic system. Also, water service would need to be provided to the building to properly operate a
hydronic system, which adds additional expense. Due to these factors, a wood boiler system is not
recommended for this building.
A wood stove system would be the most appropriate biomass heating system for the CPVC Office
building.
Biomass System Options
The most reasonable method for incorporating biomass systems into the CPVC office is by using a
residential style high efficiency wood stove. This would require a person to load and fire the stove by
hand.
A small residential style wood stove is common in Clark’s Point for auxiliary and back-up heating. The
wood stove would be easy to operate and would require minimal maintenance compared to a wood
boiler system. The wood stove would be used to provide a base heat load for the building during
occupied times. Occupants would fire the stove regularly to provide as much heating oil displacement as
they wish. The existing Toyo stoves would still be used to make up for additional required heating during
occupied times and as heaters when the building is unoccupied. For this study, one Blaze King Classic
high efficiency wood stove with an output of 48,065 BTU/hr for 12 hours, were selected as the proposed
biomass system to evaluate.
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc. 8
V. Preliminary Site Investigation – Water Treatment Plant
Building Description
The Clark’s Point Water Treatment Plant is an 800 SF single story building constructed in 1982. It is used
to draw potable water out of a well, treat it, and pump it to the village.
It is only occupied when maintenance is required; however it is heated 24/7 to prevent the water
system from freezing. There has been no energy audit of the building.
Existing Heating System
There are a total of four oil-fired space heaters in the building. Two stoves serve each half of the
building, and are used as redundant backups to each other. The two original space heaters are Preway
OVMs (56,600 Btu/hr output each) and are still functional. The newer space heaters are Monitor M-
441’s (40,000 BTU/hr output each). There is one each of the old and new heaters in each half of the
building.
Domestic Hot Water
There is an electric instantaneous water heater providing water to a laundry sink. Otherwise, all potable
water piping is to serve the Water Plant functions.
Building Envelope
The walls of the building are 2x6 wood stud construction that are estimated to have R-19 fiberglass batt
insulation. The roof is a hot roof with an unknown amount and type of insulation. It is estimated that the
roof insulation is R-19 fiberglass batt insulation. The windows are double pane windows. There is an
unheated arctic entry for the main entrance.
Available Space
There appears to be space inside the building for a residential style wood stove. However, an addition
would be needed to house a larger Garn wood boiler type system.
Street Access and Fuel Storage
The building is situated at the end of a gravel road, with a gravel pad surrounding the building. There is
plenty of appropriate space around the building for additions or new boiler buildings, or wood storage
sheds.
Building or Site constraints
No significant site constraints are present at the Water Plant.
Biomass System Integration
The building has no hydronic piping, boiler, or fin-tube baseboard. Thus to implement a wood fired
boiler system, new hydronic piping and baseboards would need to be installed.
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc. 9
A residential style high efficiency wood stove could easily be installed in the building. However, due to
the continuous heating requirement and low occupancy of the building, it is not practical to utilize a
wood stove. Due to these factors, a wood stove was not evaluated for this building.
Biomass System Options
The only practical option for incorporating biomass systems into the Water Plant is a wood boiler system
in an addition or detached building. The systems would require a person to load and fire the wood
heating systems by hand.
A wood fired boiler can be loaded and fired in batches, which heats up a large volume of water for space
heating. This allows a wood fired boiler to be loaded less times throughout the day then a wood stove,
which would need a higher loading frequency. The wood fired boiler system would be located in an
addition or detached boiler building and heating pipes would be routed to the building. Since there is
no existing hydronic system, several fan coil units would need to be installed to exchange heat from the
wood boiler system to the building. For this study, one Tarm Solo Plus 40 wood boiler with an output of
140,000 Btu/hr was used. The Tarm wood boiler would be located in an attached addition to the
building and would house a 500 gal thermal storage tank for the boiler system. New fan coil units would
deliver heat to the building from the boiler system. The Tarm system is smaller than a typical Garn
system. Please refer to the General Biomass Technology Information at the end of the report for more
information on the Tarm units.
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
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VI. Preliminary Site Investigation – City Office
Building Description
The City of Clark’s Point Office, or City Office, is a 900 SF one story building, constructed in
approximately 1987. It is used as the office space for the Mayor of Clark’s Point. The building is used
from Monday to Friday each week. An addition was added to the building at s ome point in the last 10
years; however, it is unfinished and blocked off. The building has not had an energy audit.
Existing Heating System
The building is provided with two oil-fired furnaces; however at the time of inspection neither furnace
was in working order. Significant maintenance will be required to return the furnaces to service.
Comfort heating was provided with electric unit heaters.
A 640 gallon fuel tank was located immediately outside the mechanical closet, but has advanced
corrosion and is of questionable reliability. Significant overhaul, and most likely replacement, would be
required to return the fuel tank to proper operating conditions. The fuel was used only for heating.
Domestic Hot Water
The building is plumbed, however it was winterized due to the out-of-service furnaces. Should heating
be restored, an electric instantaneous water heater provides hot water to the lavatory.
Building Envelope
The walls of the building are 2x6 wood stud construction that are estimated to have R-19 fiberglass batt
insulation. The roof is a cold roof with a vented attic space, with an unknown amount and type of
insulation because it could not be accessed. It is estimated that the roof insulation is R-25 fiberglass batt
insulation. The windows are double pane windows. There is an unheated arctic entry for the main
entrance. The building foundation is on piles and the floor of the building is not level, due to foundation
settlement. It is estimated that there is R-19 fiberglass batt insulation in the floor, as this space was not
accessible.
Available Space
There appears to be space inside the building for a residential style high efficiency wood stove. There is
no space within the building for a wood boiler. An addition or a central boiler building would be
required.
Street Access and Fuel Storage
The building is situated on a gravel road, with a gravel pad extending around the sides of the building,
suitable for access by truck. An addition or a wood storage shed would best work on the sides of the
building.
Building or Site constraints
No significant site constraints are present at the City Office.
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
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Biomass System Integration
The building has no hydronic piping, boiler, or fin-tube baseboard. Thus to implement a wood fired
boiler system, new hydronic piping and baseboards would need to be installed.
A residential style high efficiency wood stove could easily be installed in the building.
Biomass System Options
There are three options for incorporating biomass systems into the City Office:
1) A high efficiency wood stove,
2) A wood boiler system in a detached building, or
3) A large central plant wood boiler system that would serve the City Office, the Post Office, and
the Clinic.
All systems would require a person to load and fire the wood heating systems by hand.
A small residential style wood stove is common in Clark’s Point for auxiliary and back-up heating. The
wood stove would be easy to operate and would require minimal maintenance compared to a wood
boiler system. The wood stove would be used to provide a base heat load for the building during
occupied times. Occupants would fire the stove regularly to provide as much heating oil displacement as
they wish. The existing Toyo stoves would still be used to make up for additional required heating during
occupied times and as heaters when the building is unoccupied. For this study, one Blaze King Classic
high efficiency wood stove with an output of 48,065 BTU/hr for 12 hours was selected as the proposed
biomass system to evaluate.
The second option is a wood fired boiler system, which will be more expensive and require more
maintenance than a wood stove. A wood fired boiler can be loaded and fired in batches, which heats up
a large volume of water for space heating. This allows a wood fired boiler to be loaded less times
throughout the day then a wood stove, which would need a higher loading frequency. The wood fired
boiler system would be located in a detached boiler building and heating pipes would be routed to the
building, and connect to a heating coil in the existing furnace. However, due to the significant expense
of integrating into the building’s broken furnace system or installing a new hydronic system this option
is not practical at this time and was not evaluated in this study.
The third option is a large central plant wood boiler system that could serve multiple buildings. The
central plant could serve the City Office, the Post Office, and the Village Clinic. All of these buildings are
within 100 yards of each other. The buildings could be connected to a buried glycol heating loop that is
connected to a central wood fired boiler plant. This option would be the most expensive, but would
have the biggest ability to offset heating oil consumption. However, the Clinic, Post Office, and City
Office are owned by different entities, which may prove difficult to organize. A central plant system of
this size and complexity would also require a maintenance staff to properly operate and maintain the
system. The systems would utilize pumps, glycol, heat exchangers, boilers and a control system. Skilled
maintenance personnel would be needed to operate and maintain the system. Finally, it appears that
the only available land for a central plant facility would be south of the Clinic, which would be
approximately 75 yards away from the City Office. This option could be viable, but would require skilled
maintenance personnel and buy in from all of the building owners. This option was not evaluated in this
study because it is outside the scope of the project. If this option is desired, we recommend a more
detailed feasibility study. For this type of central plant, we would recommend a garn system as it has a
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc. 12
large water storage capacity, simple operation, and stores heat for a significant amount of time (so
freeze up is not an issue over a weekend or infrequent firing).
VII. Preliminary Site Investigation – Clinic
Building Description
The Clark’s Point Village Clinic is a 2,000 SF single story building constructed in 2004. The building is used
as a first aid and telemedicine facility, and has one regular occupant. It is kept heated 24/7. The health
aide is present for a regular 40-hour work week. No energy audit has been conducted at the facility.
Existing Heating System
The building is heated with an oil-fired boiler and a hydronic system. The boiler is a Weil-McLain P-WGO-
2, with an input rating of 0.7 GPH of fuel oil (75,000 But/hr Net I=B=R output). The system is well
maintained and is in good working order. A 550 gallon fuel oil tank sits behind the facility and serves
only the heating system. No spill containment is present around the tank and the fuel is used only for
heating.
Domestic Hot Water
The domestic hot water is provided through an Amtrol WH7ZDW sidearm water heater, and is
maintained in good working order. It serves lavatories, a shower/bathtub combination valve, medical
and dental sinks, and a break room sink.
Building Envelope
The walls of the building are 2x8 wood stud construction that are estimated to have R-28 fiberglass batt
insulation. The roof is a cold roof with a vented attic space, with an unknown amount and type of
insulation because it could not be accessed. It is estimated that the roof insulation is R-40 fiberglass batt
insulation. The windows are double pane windows. There is an unheated arctic entry for the main
entrance. The building foundation is on piles.
Available Space
There is no available space within the building for wood fired heating appliances. An addition or
standalone building would have to be constructed in order to be connected.
Street Access and Fuel Storage
The building is situated on a gravel road, with a gravel pad extending around the sides of the building,
suitable for access by truck. An addition or a wood storage shed would best work on the sides of the
building.
Building or Site constraints
No significant site constraints are present at the Village Clinic.
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
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Biomass System Integration
The building utilizes hydronic baseboard heat, and integration with a wood fired boiler system would be
relatively uncomplicated compared to other facilities inspected at Clark’s Point.
Biomass System Options
There are two options for incorporating biomass systems into the community:
1) A wood boiler system in a detached building, or
2) A large central plant wood boiler system that would serve the City Office, the Post Office, and
the Clark’s Point Village Clinic. All systems would require a person to load and fire the wood
heating systems by hand.
The first option is a wood fired boiler system. A wood fired boiler can be loaded and fired in batches,
which heats up a large volume of water for space heating. This allows a wood fired boiler to be loaded
perhaps once or twice throughout the day. The wood fired boiler system would be located in a detached
boiler building and heating pipes would be routed to the building. The system would be connected to
the Clinic’s existing hydronic system. For this study, one Tarm Solo Plus 30 wood boiler with an output
of 102,000 Btu/hr was used. The Tarm wood boiler would be located in an attached addition to the
building and would house a 500 gal thermal storage tank for the boiler system. The boiler system would
be connected to the existing hydronic system.
The third option is a large central plant wood boiler system that could serve multiple buildings. Please
refer to the City Office section on Biomass System Options for the description of the central plant
system.
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
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VIII. Preliminary Site Investigation – Post Office
Building Description
Evaluating the Post Office was not part of the project scope. However, during the site visit, there was
additional time available, and a walk through of the Post Office was completed. Per the scope, no
economic analysis was completed for the post office.
The Clark’s Point Post Office is a 1,000 SF single story building that was constructed in the 1980s. It is
used to receive and distribute the mail to Clark’s Point residents. Staff is present at the building for a
period after mail flights come through, until mail has finished sorting. The postal lobby is available to the
public at all hours. No energy audit has been conducted at the facility.
Existing Heating System
The building is heated primarily with an oil-fired furnace. At the time of inspection, the furnace was out
of service due to lack of maintenance. A Reznor oil-fired unit heater heats the garage, but at the time of
inspection it was also out of service due to lack of maintenance. Proper maintenance is not provided to
the building’s heating appliances to keep them in working order. The single postal office employee
utilizes electric, plug-in heaters to provide comfort heat. However, due to the size of the building, the
electric heaters cannot maintain appropriate building temperatures on cold days.
There is a 330 gallon fuel oil tank located behind the building within a gated, fenced enclosure, and was
replaced in the last 5 years due to failure of the previous fuel oil tank. No spill containment is present
around the tank and the fuel is used only for heating.
Domestic Hot Water
A point of use electric water heater is provided in the mechanical room to supply hot water to the
lavatory. However, all the plumbing in the building has been drained and winterized due to the lack of
heating in the building.
Building Envelope
The walls of the building are 2x6 wood stud construction that are estimated to have R-19 fiberglass batt
insulation. The roof is a cold roof with a vented attic space, with an unknown amount and type of
insulation because it could not be accessed. It is estimated that the roof insulation is R-25 fiberglass batt
insulation. The windows are double pane windows. There is an unheated arctic entry for the main
entrance. The building foundation is on piles.
Available Space
There appears to be space inside the building for a residential style wood stove. There is no space within
the building for a wood boiler. An addition or a central boiler building would be required.
Street Access and Fuel Storage
The building is situated on a gravel road, with a gravel pad extending around the sides of the building,
suitable for access by truck. An addition or a wood storage shed could be located on the sides of the
building.
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Building or Site constraints
No significant site constraints are present at the Post Office.
Biomass System Integration
The building has no hydronic piping, boiler, or fin-tube baseboard. Thus to implement a wood fired
boiler system, new hydronic piping and baseboards would need to be installed.
A residential style wood stove could easily be installed in the building.
Biomass System Options
Due to the fact that the existing Post Office mechanical equipment is not maintained and dysfunctional,
it does not make practical sense to install an expensive wood boiler system. A wood boiler system will
require maintenance and will likely breakdown at this building due to lack of maintenance, similar to the
existing mechanical equipment. Due to this factor, a wood boiler system is not appropriate for the Post
Office.
The recommended biomass system option is a high efficiency wood stove. The wood stove would be
easy to operate and would require minimal maintenance compared to a wood boiler system. The wood
stove would be used to provide a base heat load for the building during occupied times. Occupants
would fire the stove regularly to provide as much heating oil displacement as they wish. The existing
electric heaters would still be used to make up for additional required heating during occupied times
and when the building is unoccupied.
Another option for the Post Office would be to connect it to a central plant system. Please refer to the
City Office section on Biomass System Options for the description of the central plant system.
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
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IX. Energy Consumption and Costs
Wood Energy
The gross energy content of a cord of wood varies depending on tree species and moisture content.
Black spruce, white spruce and birch at 20% moisture content have respective gross energy contents of
15.9 MMBTU/Cord, 18.1 MMBTU/cord and 23.6 MMBTU/cord, according to the UAF Cooperative
Extension. Wet or greenwood has higher moisture contents and require additional heat to evaporate
moisture before the wood can burn. Thus, wood with higher moisture contents will have lower energy
contents. Seasoned or dry wood will typically have 20% moisture content. For this study, cord wood
was estimated to have 16.0 MMBTU/cord. This is a conservative estimate based on the fact that the
community has access to both spruce and birch. To determine the delivered $/MMBTU of the biomass
system, a 75% efficiency for the high efficiency wood stoves and Tarm wood boilers was assumed. This
is a conservative estimate based on manufacturer documentation.
Energy Costs
Clark’s Point has a unique energy pricing situation due to the flat rate electricity price throughout the
village. Currently, residences pay a $250/month flat rate for electricity. Electricity is not charged per
kWh and a building can consume as much electricity as can be produced by the village’s generators and
distributed by the small electric grid. This scenario can make electricity the cheapest heating source (to
the consumer, but not for utility) if the building consumes enough electricity. For example, two 3kW
space heaters operating 24/7 for one month will cost approximately $16.90 per MMBTU, which is
approximately 60% cheaper than heating with heating oil and 40% cheaper than heating with wood.
Due to this flat rate, most residences use electric resistance heaters as their primary heat source.
Toyo/Monitor stoves are used as back up heaters when the electric heaters cannot provide full heating.
This unique situation should be considered when deciding to implement wood heating systems, as
electricity can be the cheapest heat source to consumers in the village. In this study, all of the five
buildings evaluated utilize fossil fuel as their primary heat source. Therefore, the proposed biomass
system is compared to fossil fuel in this study. If the Utility/City changes the electricity payment
situation to be per kWh (like most villages), electricity would most likely not be the cheapest heating
source.
Fuel oil is shipped into Clark’s Point by barge and currently costs $6.00/gal. For this study, the energy
content of fuel oil is based on 134,000 BTU/gal, according to the UAF Cooperative Extension.
Cord wood is sold in Clark’s Point for approximately $330 per cord.
The table below shows the energy comparison of different fuel types. The system efficiency is used to
calculate the delivered MMBTU’s of energy to the building. The delivered cost of energy to the building,
in $/MMBTU, is the most accurate way to compare costs of different energy types. As shown below,
cord wood is approximately half the cost of heating oil based on the $/MMBTU delivered to the building
heat load.
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
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Fuel Type Units Gross
BTU/unit
System
Efficiency $/unit Delivered
$/MMBTU
Cord Wood cords 16,000,000 75% $330 $27.50
Fuel Oil gal 134,000 80% $6.00 $55.97
Electricity kWh 3,413 99% $250/month
Flat Rate
Not
Comparable
Table 2 – Energy Comparison
Existing Fuel Oil Consumption
Complete heating oil bills were not provided for the five Clark’s Point buildings evaluated. The heating
oil consumption for each building was estimated based on interviews with Mr. Mariano Floresta. The
heating oil consumption for each building is shown below.
Building Name Fuel Type
Avg. Annual
Consumption Net MMBTU/yr Annual Fuel Cost
Community Center Fuel Oil 4,000 gal 428.8 $24,000
CPVC Office Fuel Oil 2,000 gal 214.4 $12,000
Water Treatment
Plant Fuel Oil 2,000 gal 214.4 $12,000
City Office Fuel Oil 1,500 gal 160.8 $9,000
Clinic Fuel Oil 2,000 gal 214.4 $12,000
Table 3 – Existing Fuel Oil Consumption
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
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Biomass System Consumption
The proposed biomass system for each building is shown in the table below.
High Efficiency Wood Stoves: While wood stoves are capable of providing the majority of the space heat
for each building, a conservative estimate of 50% heating oil offset was used for the study. Due to the
fact that the buildings are not occupied constantly and that the wood stoves are hand fired, a 50%
heating oil offset is a realistic estimate for this study (as wood stoves would not be used when building is
unoccupied). If the building tenants wish to offset more heating oil, the wood stove can be fired on a
more frequent schedule.
Building Name Fuel Type % Heating
Source
Net
MMBTU/yr
Annual
Consumption
Energy
Cost
Total
Energy Cost
Community
Center
Cord
Wood 50% 214.4 17.9 cords $5,896
$17,896
Fuel Oil 50% 214.4 2,000 gal $12,000
CPVC Office
Cord
Wood 50% 107.2 8.9 cords $2,948
$8,948
Fuel Oil 50% 107.2 1,000 gal $6,000
City Office
Cord
Wood 50% 80.4 6.7 cords $2,211
$6,711
Fuel Oil 50% 80.4 750 gal $4,500
Table 4 – High Efficiency Wood Stove Fuel Consumption
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High Efficiency Wood Boilers: For this study it is estimated that the Tarm wood boiler systems will
offset 85% of heating oil consumption for the building. The remaining 15% of the heat for the building
will come from the existing heating oil-fired units. Annual energy costs include wood and fuel oil costs.
Since the community is on a flat electric rate, there is no additional cost for the additional electricity
required to operate the Tarm boiler heating system.
Building Name Fuel Type % Heating
Source
Net
MMBTU/yr
Annual
Consumption
Energy
Cost
Total
Energy Cost
Water
Treatment
Plant
Cord
Wood 85% 182.2 15.2 cords $5,012
$6,812 Fuel Oil 15% 32.2 300 gal $1,800
Electricity N/A N/A 2,190 kWh $0
Clinic
Cord
Wood 85% 182.2 15.2 cords $5,012
$6,812 Fuel Oil 15% 32.2 300 gal $1,800
Electricity N/A N/A 2,190 kWh $0
Table 5 – High Efficiency Wood Boiler Fuel Consumption
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X. Preliminary Cost Estimating
An estimate of probable costs was completed for the proposed biomass system for each building. The
estimate includes general conditions and overhead and profit for the general contractor. A 10% remote
factor was used to account for increased shipping and installation costs in Clark’s Point. Engineering
design and permitting was estimated at 15% and a 10% contingency was used. Note that the material
costs for the Tarm Solo Plus 30 and 40 are approximately the same, resulting in identical project capital
costs for these two options.
Estimate of Probable Costs for one High Efficiency Wood Stove in Clark’s Point
Category Description Unit Unit Cost Quantity Cost
High Efficiency Wood Stove Wood Stove Each $2,500.00 1 $2,500
Blower Fan Each $500.00 1 $500
Stack Each $500.00 1 $500
Subtotal $3,500
Installation Area Prep hrs $150.00 8 $1,200
Stove and Chimney
Install hrs $150.00 8 $1,200
Additional Parts
Allowance Each $1,000.00 1 $1,000
Subtotal $3,400
Shipping 600 lbs Shipping Job $1,500.00 1 $1,500
Subtotal $1,500
Subtotal Material and Installation Cost
$8,400
General Conditions 5% $420
Subtotal $8,820
Overhead and Profit 5% $441
Subtotal $9,261
Remote Factor 10% $926
Subtotal $10,187
Design Fees and Permitting 15% $1,528
Subtotal $11,715
Contingency 10% $1,172
Total Project Cost $12,887
Table 6 – Estimate of Probable Costs for one High Efficiency Wood Stove in Clark’s Point
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
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Estimate of Probable Costs for Tarm Solo Plus 30 or 40 in Clark’s Point
Category Description Unit Unit Cost Quantity Cost
Site Work NFS Fill SF $3.38 500 $1,690
Site Grading Job $3,500.00 1 $3,500
Subtotal $5,190
Wood Boiler and Boiler Addition Tarm Solo Unit Job $12,885.00 1 $12,885
500 gal Storage
Tank each $10,000.00 1 $10,000
Installation Job $17,000.00 1 $17,000
Boiler Addition each $40,000.00 1 $40,000
Shipping Job $5,000.00 1 $5,000
$84,885
Interior Mechanical & Electrical
HX, Piping &
Materials Bldg $25,000.00 1 $25,000
Subtotal $25,000
Subtotal Material and Installation Cost
$115,075
General Conditions 10% $11,508
Subtotal $126,583
Overhead and Profit 10% $12,658
Subtotal $139,241
Remote Factor 10% $13,924
Subtotal $153,165
Design Fees and Permitting 15% $22,975
Subtotal $176,140
Contingency 10% $17,614
Total Project Cost $193,754
Table 7 – Estimate of Probable Costs for Tarm Solo Plus 30 or 40 in Clark’s Point
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XI. Economic Analysis
The following assumptions were used to complete the economic analysis for the proposed biomass
systems in Clark’s Point.
Inflation Rates
Discount Rate for Net Present Value Analysis 3%
Wood Fuel Escalation Rate 3%
Fossil Fuel Escalation Rate 5%
Electricity Escalation Rate 3%
O&M Escalation Rate 2%
Table 8 – Inflation rates
The real discount rate, or minimum attractive rate of return, is 3.0% and is the current rate used for all
Life Cycle Cost Analysis by the Alaska Department of Education and Early Development. This is a typical
rate used for completing economic analysis for public entities in Alaska. The escalation rates used for
the wood, heating oil, electricity and O&M rates are based on rates used in the Alaska Energy Authority
funded 2012 biomass pre-feasibility studies. These are typical rates used for this level of evaluation and
were used so that results are consistent and comparable to the 2012 studies.
O&M Costs
Non-fuel related operations and maintenance costs (O&M) were estimated at $500 and $50 per year,
for the Tarm Boilers and Blaze King Classic Wood Stoves, respectively. For the first two years of service,
an additional $500 and $50 per year were added to the Tarm Boilers and Blaze King Classic Wood
Stoves, respectively, to account for maintenance staff getting used to operating the new system.
Definitions
There are many different economic terms used in this study. A listing of all of the terms with their
definition is provided below for reference.
Economic Term Description
Project Capital Cost This is the opinion of probable cost for designing and constructing the
project.
Simple Payback The Simple Payback is the Project Capital Cost divided by the first year
annual energy savings. The Simple Payback does not take into account
escalated energy prices.
Present Value of Project
Benefits (20 year life)
The present value of all of the heating oil that would have been consumed by
the existing heating oil-fired heating system, over a 20 year period.
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
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Economic Term Description
Present Value of
Operating Costs (20 year
life)
The present value of all of the proposed biomass systems operating costs
over a 20 year period. This includes wood fuel, additional electricity, and
O&M costs for the proposed biomass system to provide 85% of the building’s
heat. It also includes the heating oil required for the existing oil-fired boilers
to provide the remaining 15% of heat to the building.
Benefit / Cost Ratio of
Project (20 year life)
This is the benefit to cost ratio over the 20 year period. A project that has a
benefit to cost ratio greater 1.0 is economically justified. It is defined as
follows:
Where:
PV = The present value over the 20 year period
Reference Sullivan, Wicks and Koelling, “Engineering Economy”, 14th ed.,
2009, pg. 440, Modified B-C Ratio.
Net Present Value (20
year life)
This is the net present value of the project over a 20 year period. If the
project has a net present value greater than zero, the project is economically
justified. This quantity accounts for the project capital cost, project benefits
and operating costs.
Year Accumulated Cash
Flow > Project Capital
Cost
This is the number of years it takes for the accumulated cash flow of the
project to be greater than or equal to the project capital cost. This is similar
to the project’s simple payback, except that it incorporates the inflation
rates. This quantity is the payback of the project including escalating energy
prices and O&M rates. This quantity is calculated as follows:
Where:
J = Year that the accumulated cash flow is greater than or equal to the
Project Capital Cost.
= Project Cash flow for the kth year.
Table 9 – Economic Definitions
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Results
The economic analysis was completed in order to determine the simple payback, benefit to cost ratio,
and net present value of the proposed biomass system at each building. The results are shown in the
table below. Note that due to the fact that many of the buildings have similar heating oil consumption
estimates and similar project costs, the results for the CPVC Office, Water Treatment Plant and Clinic
have similar numbers.
Based on the economic analysis it was determined that high efficiency wood stoves for the Community
Center, CPVC Office and City Office have benefit to cost ratios above 1.0, and would typically be
considered economically justified. The driving factors that make these projects cost effective are their
relatively low project capital cost, combined with the high price of heating oil. A high efficiency wood
stove is much cheaper than utilizing a high efficiency wood boiler because all the necessary hydronic
piping required integrating into the building and building additions are not needed.
The Tarm wood boiler systems for the Water Treatment Plant and the Clinic have benefit to cost ratios
less than 1.0, and would not be typically considered economically justified at this time. This is due to
relatively high project capital costs together with limited heating oil displacement. A sensitivity analysis
for these two buildings is shown in the next section.
Economic Analysis Results
Building
Community
Center CPVC Office Water
Treatment Plant
Proposed Biomass System
Two Blaze King
Classic High
Efficiency Wood
Stoves
One Blaze King
Classic High
Efficiency
Wood Stove
Tarm Solo Plus
40 Wood Boiler
Project Capital Cost ($25,774) ($12,887) ($193,754)
Simple Payback 4.3 years 4.3 years 46.3 years
Present Value of Project Benefits (20 year life) $562,880 $281,440 $281,440
Present Value of Operating Costs (20 year life) ($397,122) ($198,732) ($149,444)
Benefit / Cost Ratio of Project (20 year life) 6.43 6.42 0.68
Net Present Value (20 year life) $139,984 $69,821 ($61,758)
Year Accumulated Cash Flow is Net Positive First Year First Year First Year
Year Accumulated Cash Flow > Project Capital
Cost
3.9 years 3.9 years >20 years
Table 10 – Economic Analysis Results
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc. 25
Economic Analysis Results
Building City Office Clinic
Proposed Biomass System
One Blaze King Classic
High Efficiency Wood
Stove
Tarm Solo Plus 30 Wood
Boiler
Project Capital Cost ($12,887) ($193,754)
Simple Payback 5.9 years 46.3 years
Present Value of Project Benefits (20 year life) $211,080 $281,440
Present Value of Operating Costs (20 year life) ($149,455) ($149,444)
Benefit / Cost Ratio of Project (20 year life) 4.78 0.68
Net Present Value (20 year life) $48,738 ($61,758)
Year Accumulated Cash Flow is Net Positive First Year First Year
Year Accumulated Cash Flow > Project Capital
Cost
5.0 years >20 years
Table 11 – Economic Analysis Results - Continued
Sensitivity Analysis
A sensitivity analysis was completed for the Tarm wood boiler systems at the Water Treatment Plant
and Clinic to show how changing heating oil costs and wood costs affect the B/C ratios of these projects.
As heating oil costs increase and wood costs decrease, the project becomes more economically viable.
Note that results of these two buildings are identical because they have the same heating oil
consumption and project capital costs.
Water Treatment Plant and
Clinic B/C Ratios
Wood Cost ($/cord)
$264/cord $330/cord $396/cord
Heating Oil Cost
($/gal)
$4.80/gal 0.53 0.43 0.33
$6.00/gal 0.78 0.68 0.58
$7.20/gal 1.03 0.93 0.83
Table 12 – Water Treatment Plant and Clinic Analysis
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XII. Forest Resource and Fuel Availability Assessments
Forest Resource Assessments
Fuel availability assessments were not available for the Clark’s Point area. During the site visit it was
found that the land surrounding the Clark’s Point village has few trees. Wood harvesting is typically
accomplished 10 to 15 miles outside of the village where the wood resource exists. There are limited
roads in the village and the wood resource can only be accessed by snow machine during the winter
months. It typically takes one full day by snow machine to gather a cord of wood, according to locals.
Most wood currently being used by the village is for personal steam baths. Due to the effort involved
with gathering wood, wood is not used heavily to supplement heating oil consumption for space
heating.
Per Coffman’s discussions with Mr. Will Putman with the State Forestry Service, most of the permits for
wood harvesting are owned and controlled by village corporations within the state. If harvesting is to
take place in these areas, permission will need to be obtained from the village corporation prior to
harvesting. If more than 40 acres per year or 50 cords of wood are collected per year, the harvesting is
classified as a commercial operation. For a commercial harvest, the practices outlined in the Forest
Resources and Practices Act will need to be followed. The Forest Resource and Practices Act protects the
water and habitat within the harvesting site and applies to state, federal, and native corporation land. If
less than 40 cords of wood are used per year, the use is considered as a personal use and a commercial
permit is not required.
Air Quality Permitting
Currently, air quality permitting is regulated according to the Alaska Department of Environmental
Conservation Section 18 AAC 50 Air Quality Control regulations. Per these regulations, a minor air
quality permit is required if a new wood boiler or wood stove produces one of the following conditions
per Section 18 AAC 50.502 (C)(1): 40 tons per year (TPY) of carbon dioxide (CO2), 15 TPY of particulate
matter greater than 10 microns (PM-10), 40 TPY of sulfur dioxide, 0.6 TPY of lead, 100 TPY of carbon
monoxide within 10 kilometers of a carbon monoxide nonattainment area, or 10 TPY of direct PM -2.5
emissions. These regulations assume that the device will operate 24 hours per day, 365 days per year
and that no fuel burning equipment is used. If a new wood boiler or wood stove is installed in addition
to a fuel burning heating device, the increase in air pollutants cannot exceed the following per AAC
50.502 (C)(3): 10 TPY of PM-10, 10 TPY of sulfur dioxide, 10 TPY of nitrogen oxides, 100 TPY of carbon
monoxide within 10 kilometers of a carbon monoxide nonattainment area, or 10 TPY of direct PM -2.5
emissions. Per the Wood-fired Heating Device Visible Emission Standards (Section 18 AAC 50.075), a
person may not operate a wood-fired heating device in a manner that causes black smoke or visible
emissions that exceed 50 percent opacity for more than 15 minutes in any hour in an area where an air
quality advisory is in effect.
From Coffman’s discussions with Patrick Dunn at the Alaska Department of Environmental Conservation,
these regulations are focused on permitting industrial applications of wood burning equipment. In his
opinion, it would be unlikely that an individual wood boiler would require an air quality permit unless
several boilers were to be installed and operated at the same site. If several boilers were installed and
operated together, the emissions produced could be greater than 40 tons of CO2 per year. This would
require permitting per AAC 50.502 (C)(1) or (C)(3). Permitting would not be required on the residential
wood fired stoves unless they violated the Wood-fired Heating Device Visible Emission Standards
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc. 27
(Section 18 AAC 50.075). The current similar systems installed in Alaska do not require and did not
obtain air quality permits.
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
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XIII. General Biomass Technology Information
Heating with Wood Fuel
Wood fuels are among the most cost-effective and reliable sources of heating fuel for communities
adjacent to forestland when the wood fuels are processed, handled, and combusted appropriately.
Compared to other heating energy fuels, such as oil and propane, wood fuels typically have lower
energy density and higher associated transportation and handling costs. Due to this low bulk density,
wood fuels have a shorter viable haul distance when compared to fossil fuels. This short haul distance
also creates an advantage for local communities to utilize locally-sourced wood fuels, while
simultaneously retaining local energy dollars.
Most villages in rural Alaska are particularly vulnerable to high energy prices due to the large number of
heating degree days and expensive shipping costs. For many communities, wood-fueled heating can
lower fuel costs. For example, cordwood sourced at $250 per cord is just 25% of the cost per MMBTU as
#1 fuel oil sourced at $7 per gallon. In addition to the financial savings, the local communities also
benefit from the multiplier effect of circulating energy dollars within the community longer, more stable
energy prices, job creation, and more active forest management.
In all of the Lake and Peninsula Communities studied, the community’s wood supply and demand are
isolated from outside markets. The local cordwood market is influenced by land ownership, existing
forest management and ecological conditions, local demand and supply, and the State of Alaska Energy
Assistance program.
Types of Wood Fuel
Wood fuels are specified by energy density, moisture content, ash content, and granulometry. Each of
these characteristics affects the wood fuel’s handling characteristics, storage requirements, and
combustion process. Higher quality fuels have lower moisture, ash, dirt, and rock contents , consistent
granulometry, and higher energy density. Different types of fuel quality can be used in wood heating
projects as long as the infrastructure specifications match the fuel content characteristics. Typically,
lower quality fuel will be the lowest cost fuel, but it will require more expensive storage, handling, and
combustion infrastructure, as well as additional maintenance.
Projects in rural Alaska must be designed around the availability of wood fuels. Some fuels can be
harvested and manufactured on site, such as cordwood, woodchips, and briquettes. The economic
feasibility of manufacturing on site is determined by a financial assessment of the project. Typically,
larger projects offer more flexibility in terms of owning and operating the wood harvesting and
manufacturing equipment, such as a wood chipper, splitter, or equipment to haul wood out of forest,
than smaller projects.
Due to the limited wood fuel demand, large financial obligations and operating complexities, it is
unlikely that the Lake and Peninsula communities in this study will be able to manufacture pellets.
However, some communities may be able to manufacture bricks or fire logs made from pressed wood
material. These products can substitute for cordwood in woodstoves and boilers, while reducing supply
pressure on larger diameter trees that are generally preferred for cordwood.
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc. 29
High Efficiency Cord Wood Boilers
High Efficiency Low Emission (HELE) cordwood boilers are designed to burn cordwood fuel cleanly and
efficiently. The boilers use cordwood that is typically seasoned to 25% moisture content (MC) or less and
meet the dimensions required for loading and firing. The amount of cordwood burned by the boiler will
depend on the heat load profile of the building and the utilization of the fuel oil system as back up.
Three HELE cordwood boiler suppliers include Garn (www.garn.com), Greenwood
(www.greenwoodusa.com) and TarmUSA (www.woodboilers.com). All three of these suppliers have
units operating in Alaska. Greenwood and TarmUSA have a number of residential units operating in
Alaska and have models that range between 100,000 to 300,000 BTU/hr. Garn boilers, manufactured by
Dectra Corporation, are used in Tanana, Kasilof, Dot Lake, Thorne Bay, Coffman Cove and other
locations to heat homes, washaterias, schools, and community buildings.
The Garn boiler has a unique construction, which is basically a wood boiler housed in a large water tank.
Garn boilers come in several sizes and are appropriate for facilities using 100,000 to 1,000,000 BTUs per
hour. The jacket of water surrounding the fire box absorbs heat and is piped into buildings via a heat
exchanger, and then transferred to an existing building heating system, infloor radiant tubing, unit
heaters, or baseboard heaters. In installations where the Garn boiler is in a detached building, there are
additional heat exchangers, pumps and a glycol circulation loop that are necessary to transfer heat to
the building while allowing for freeze protection. Radiant floor heating is the most efficient heating
method when using wood boilers such as Garns, because they can operate using lower supply water
temperatures compared to baseboards.
Garn boilers are approximately 87% efficient and store a large quantity of water. For example, the Garn
WHS-2000 holds approximately 1,825 gallons of heated water. Garns also produce virtually no smoke
when at full burn, because of a primary and secondary gasification (2,000 ºF) burning process. Garns are
manually stocked with cordwood and can be loaded multiple times a day during periods of high heating
demand. Garns are simple to operate with only three moving parts: a handle, door and blower. Garns
produce very little ash and require minimal maintenance. Removing ash and inspecting fans are typical
maintenance requirements. Fans are used to produce a draft that increases combustion temperatures
and boiler efficiency. In cold climates, Garns can be equipped with exterior insulated storage tanks for
extra hot water circulating capacity. Most facilities using cordwood boilers keep existing oil-fired
systems operational to provide heating backup during biomass boiler downtimes and to provide
additional heat for peak heating demand periods.
Low Efficiency Cord Wood Boilers
Outdoor boilers are categorized as low-efficiency, high emission (LEHE) systems. These boiler systems
are not recommended as they produce significant emission issues and do not combust wood fuels
efficiently or completely, resulting in significant energy waste and pollution. These systems require
significantly more wood to be purchased, handled and combusted to heat a facility as compared to a
HELE system. The Alaska Department of Environmental Conservation has issued nuisance abatement
orders for air pollution for outdoor wood boilers in Fairbanks. Fairbanks is ranked number four on Time
Magazine's list of most air polluted cities in America. Additionally, several states have placed a
moratorium on installing LEHE boilers because of air quality issues (Washington). These LEHE systems
can have combustion efficiencies as low as twenty five (25%) percent and produce more than nine times
the emission rate of standard industrial boilers. In comparison, Garns can operate around 87%
efficiency.
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc. 30
High Efficiency Wood Stoves
Newer high efficiency wood stoves are available on the market that produce minimal smoke, minimal
ash and require less firewood. New EPA-certified wood stoves produce significantly less smoke than
older uncertified wood stoves. High efficiency wood stoves are easy to operate with minimal
maintenance compared to other biomass systems. The Blaze King Classic high efficiency wood stove
(www.blazeking.com) is a recommended model, due to its built-in thermostats that monitor the heat
output of the stove. This stove automatically adjusts the air required for combustion. This unique
technology, combined with the efficiencies of a catalytic combustor with a built-in thermostat, provides
the longest burn times of any wood stove. The Blaze King stove allows for optimal combustion and less
frequent loading and firing times.
Bulk Fuel Boilers
Bulk fuel boilers usually burn wood chips, sawdust, bark or pellets and are designed around the wood
resources that are available from the local forests or local industry. Several large facilities in Tok, Craig,
and Delta Junction (Delta Greely High School) are using bulk fuel biomass systems. Tok uses a
commercial grinder to process woodchips. The chips are then dumped into a bin and are carried by a
conveyor belt to the boiler. The wood fuel comes from timber scraps, local sawmills and forest thinning
projects. The Delta Greely High School has a woodchip bulk fuel boiler that heats the 77,000 square foot
facility. The Delta Greely system, designed by Coffman engineers, includes a completely separate boiler
building which includes chip storage bunker and space for storage of tractor trailers full of chips (so
handling of frozen chips could be avoided). Woodchips are stored in the concrete bunker and augers
move the material on a conveyor belt to the boilers. The automated fuel handling requirements for bulk
fuel systems are not cost-effective for small and medium sized structures due to higher maintenance
costs and complexities. Due to these reasons, a bulk fuel boiler system is not recommended for small
rural communities in Alaska with limited financial and human resources.
Grants
There are many grant opportunities for biomass work state, federal, and local for feasibility studies,
design and construction. If a project if determined to be pursued, a thorough search of websites and
discussions with the AEA Biomass group would be recommended to make sure no possible funding
opportunities are missed. Below are some funding opportunities and existing past grants that have
been awarded.
Currently, there is a funding opportunity for tribal communities that develop clean and renewable
energy resources through the U.S. Department of Energy. On April 30, 2013, the Department of Energy
announced up to $7 million was available to deploy clean energy projects in tribal communities to
reduce reliance on fossil fuel and promote economic development on tribal lands. The Energy
Department’s Tribal Energy Program, in cooperation with the Office of Indian Energy, will help Native
American communities, tribal energy resource development organizations, and tribal consortia to install
community or facility scale clean energy projects.
http://apps1.eere.energy.gov/tribalenergy/
The Department of Energy (DOE), Alaska Native programs, focus on energy efficiency and add ocean
energy into the mix. In addition the communities are eligible for up to $250,000 in energy-efficiency aid.
The Native village of Kongiganak will get help strengthening its wind-energy infrastructure, increasing
energy efficiency and developing “smart grid technology”. Koyukuk will get help upgrading its energy
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc. 31
infrastructure, improving energy efficiency and exploring biomass options. The village of Minto will
explore all the above options as well as look for solar-energy ideas. Shishmaref, an Alaska Native village
faced climate-change-induced relocation, will receive help with increasing energy sustainability and
building capacity as it relocates. And the Yakutat T’lingit Tribe will also study efficiency, biomass and
ocean energy. This DOE program would be a viable avenue for biomass funding.
http://energy.gov/articles/alaska-native-communities-receive-technical-assistance-local-clean-energy-
development
The city of Nulato was awarded a $40,420 grant for engineering services for a wood energy project by
the United States Department of Agriculture (USDA) and the United States Forest Service. Links
regarding the award of the Woody Biomass Utilization Project recipients are shown below:
http://www.fs.fed.us/news/2012/releases/07/renewablewoods.shtml
http://www.usda.gov/wps/portal/usda/usdahome?contentid=2009/08/0403.xml
Delta Junction was awarded a grant for engineering from the Alaska Energy Authority from the
Renewable Energy Fund for $831,203. This fund provides assistance to utilities, independent power
producers, local governments, and tribal governments for feasibility studies, reconnaissance studies,
energy resource monitoring, and work related to the design and construction of eligible facilities.
http://www.akenergyauthority.org/re-fund-6/4_Program_Update/FinalREFStatusAppendix2013.pdf
http://www.akenergyauthority.org/PDF%20files/PFS-BiomassProgramFactSheet.pdf
http://www.akenergyauthority.org/RenewableEnergyFund/RFA_Project_Locations_20Oct08.pdf
The Alaska Wood Energy Development Task Group (AWEDTG) consists of a coalition of federal and state
agencies and not-for-profit organizations that have signed a Memorandum of Understanding (MOU) to
explore opportunities to increase the utilization of wood for energy and biofuels production in Alaska. A
pre-feasibility study for Aleknagik was conducted in 2012 for the AWEDTG. The preliminary costs for the
biomass system(s) are $346,257 for the city hall and health center system and $439,096 for the city hall,
health center, and future washeteria system.
http://www.akenergyauthority.org/biomasswoodenergygrants.html
http://www.akenergyauthority.org/BiomassWoodEnergy/Aleknagik%20Final%20Report.pdf
The Emerging Energy Technology Fund grand program provides funds to eligible applicants for
demonstrations projects of technologies that have a reasonable expectation to be commercially viable
within five years and that are designed to: test emerging energy technologies or methods of conserving
energy, improve an existing energy technology, or deploy an existing technology that has not previously
been demonstrated in Alaska.
http://www.akenergyauthority.org/EETFundGrantProgram.html
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc.
Appendix A
Site Photos
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc.
1. CPVC Office - Elevation 2. CPVC Office - Elevation
3. CPVC Office - Elevation 4. CPVC Office – Site Access
5. CPVC Office - Toyostove 6. CPVC Office - Office
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc.
7. Community Center - Elevation 8. Community Center - Elevation
9. Community Center - Elevation 10. Community Center - Elevation
11. Community Center - Toyostove 12. Community Center – Abandoned boiler
system
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc.
13. Water Treatment Facility - Elevation 14. Water Treatment Facility - Elevation
15. Water Treatment Facility - Elevation 16. Water Treatment Facility – Heating oil
furnaces
17. Community Building – Electric hot water
heater 18. Community Building – Electric heater
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc.
19. City Office - Elevation 20. City Office - Elevation
21. City Office - Elevation 22. City Office - Site access
23. City Office – Heating oil furnace #1 24. City Office – Heating oil furnace #2
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc.
25. Post Office - Elevation 26. Post Office - Elevation
27. Post Office - Elevation 28. Post Office – Electric hot water heater
29. Post Office –Heating oil unit heater 30. Post Office –Heating oil furnace
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc.
31. Clinic – Elevation 32. Clinic – Elevation
33. Clinic – Elevation 34. Clinic – Boiler room
35. Clinic – Heating oil boiler 36. Clinic – Radiant heating manifold
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc.
Appendix B
Economic Analysis Spreadsheet
Clarks Point - City OfficeClarks Point, AlaskaProject Capital Cost($12,887)Simple Payback = Total Project Cost / First Year Cost Savings5.9 yearsPresent Value of Project Benefits (20 year life)$211,080Present Value of Operating Costs (20 year life)($149,455)Benefit / Cost Ratio of Project (20 year life)4.78Net Present Value (20 year life)$48,738Year Accumulated Cash Flow is Net PositiveFirst YearYear Accumulated Cash Flow > Project Capital Cost5.0 yearsDiscount Rate for Net Present Value Analysis3%Wood Fuel Escalation Rate3%Fossil Fuel Escalation Rate5%Electricity Escalation Rate3%O&M Escalation Rate2%YearYearYearYearYearYearYearYearYearYearYearYearYearYearYearYearYearYearYearYear1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20Existing Heating System Operating CostsExisting Heating Oil Consumption$6.001,500gal$9,000$9,450$9,923$10,419$10,940$11,487$12,061$12,664$13,297$13,962$14,660$15,393$16,163$16,971$17,819$18,710$19,646$20,628$21,660$22,743Biomass System Operating CostsWood Fuel (Delivered to site)$330.0050%6.7cord($2,211)($2,277)($2,346)($2,416)($2,488)($2,563)($2,640)($2,719)($2,801)($2,885)($2,971)($3,061)($3,152)($3,247)($3,344)($3,445)($3,548)($3,654)($3,764)($3,877)Fossil Fuel$6.0050%750gal($4,500)($4,725)($4,961)($5,209)($5,470)($5,743)($6,030)($6,332)($6,649)($6,981)($7,330)($7,697)($8,081)($8,485)($8,910)($9,355)($9,823)($10,314)($10,830)($11,371)Electricity$0.000kWh$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0Operation and Maintenance Costs($50)($51)($52)($53)($54)($55)($56)($57)($59)($60)($61)($62)($63)($65)($66)($67)($69)($70)($71)($73)Additional Operation and Maintenance Costs for first 2 years($50)($51)$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0Total Operating Costs($6,811)($7,104)($7,359)($7,678)($8,012)($8,362)($8,727)($9,109)($9,508)($9,926)($10,362)($10,819)($11,297)($11,797)($12,320)($12,867)($13,440)($14,039)($14,665)($15,321)Annual Operating Cost Savings$2,189 $2,346 $2,564 $2,740 $2,927 $3,125 $3,334 $3,555 $3,789 $4,036 $4,298 $4,574 $4,866 $5,174 $5,499 $5,843 $6,206 $6,590 $6,994 $7,421Accumulated Cash Flow$2,189 $4,535 $7,098 $9,838 $12,766 $15,891 $19,225 $22,780 $26,569 $30,605 $34,903 $39,477 $44,342 $49,516 $55,016 $60,859 $67,065 $73,655 $80,649 $88,071Net Present Value($10,762) ($8,551) ($6,205) ($3,770) ($1,245)$1,372 $4,083 $6,889 $9,794 $12,797 $15,902 $19,110 $22,423 $25,843 $29,373 $33,015 $36,769 $40,640 $44,629 $48,738Energy UnitsEconomic Analysis ResultsInflation RatesDescription Unit CostHeating Source ProportionAnnual Energy Units
Clarks Point - ClinicClarks Point, AlaskaProject Capital Cost($193,754)Simple Payback = Total Project Cost / First Year Cost Savings46.3 yearsPresent Value of Project Benefits (20 year life)$281,440Present Value of Operating Costs (20 year life)($149,444)Benefit / Cost Ratio of Project (20 year life)0.68Net Present Value (20 year life)($61,758)Year Accumulated Cash Flow is Net PositiveFirst YearYear Accumulated Cash Flow > Project Capital Cost>20 yearsDiscount Rate for Net Present Value Analysis3%Wood Fuel Escalation Rate3%Fossil Fuel Escalation Rate5%Electricity Escalation Rate3%O&M Escalation Rate2%YearYearYearYearYearYearYearYearYearYearYearYearYearYearYearYearYearYearYearYear1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20Existing Heating System Operating CostsExisting Heating Oil Consumption$6.002,000gal$12,000$12,600$13,230$13,892$14,586$15,315$16,081$16,885$17,729$18,616$19,547$20,524$21,550$22,628$23,759$24,947$26,194$27,504$28,879$30,323Biomass System Operating CostsWood Fuel (Delivered to site)$330.0085%15.2cord($5,016)($5,166)($5,321)($5,481)($5,646)($5,815)($5,989)($6,169)($6,354)($6,545)($6,741)($6,943)($7,152)($7,366)($7,587)($7,815)($8,049)($8,291)($8,539)($8,796)Fossil Fuel$6.0015%300gal($1,800)($1,890)($1,985)($2,084)($2,188)($2,297)($2,412)($2,533)($2,659)($2,792)($2,932)($3,079)($3,233)($3,394)($3,564)($3,742)($3,929)($4,126)($4,332)($4,549)Electricity$0.002,190kWh$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0Operation and Maintenance Costs($500)($510)($520)($531)($541)($552)($563)($574)($586)($598)($609)($622)($634)($647)($660)($673)($686)($700)($714)($728)Additional Operation and Maintenance Costs for first 2 years($500)($510)$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0Total Operating Costs($7,816)($8,076)($7,826)($8,095)($8,375)($8,664)($8,965)($9,276)($9,599)($9,935)($10,283)($10,644)($11,018)($11,407)($11,811)($12,230)($12,665)($13,116)($13,585)($14,073)Annual Operating Cost Savings$4,184 $4,524 $5,404 $5,796 $6,211 $6,651 $7,117 $7,609 $8,130 $8,681 $9,264 $9,880 $10,532 $11,221 $11,948 $12,717 $13,530 $14,388 $15,294 $16,251Accumulated Cash Flow$4,184 $8,708 $14,111 $19,907 $26,119 $32,770 $39,886 $47,495 $55,626 $64,307 $73,571 $83,451 $93,983 $105,204 $117,152 $129,870 $143,400 $157,787 $173,081 $189,332Net Present Value($189,692) ($185,428) ($180,483) ($175,333) ($169,975) ($164,405) ($158,618) ($152,612) ($146,381) ($139,921) ($133,228) ($126,299) ($119,127) ($111,709) ($104,039) ($96,114) ($87,929) ($79,477) ($70,755) ($61,758)Energy UnitsHeating Source ProportionEconomic Analysis ResultsInflation RatesDescription Unit CostAnnual Energy Units
Clarks Point - Community CenterClarks Point, AlaskaProject Capital Cost($25,774)Simple Payback = Total Project Cost / First Year Cost Savings4.3 yearsPresent Value of Project Benefits (20 year life)$562,880Present Value of Operating Costs (20 year life)($397,122)Benefit / Cost Ratio of Project (20 year life)6.43Net Present Value (20 year life)$139,984Year Accumulated Cash Flow is Net PositiveFirst YearYear Accumulated Cash Flow > Project Capital Cost3.9 yearsDiscount Rate for Net Present Value Analysis3%Wood Fuel Escalation Rate3%Fossil Fuel Escalation Rate5%Electricity Escalation Rate3%O&M Escalation Rate2%YearYearYearYearYearYearYearYearYearYearYearYearYearYearYearYearYearYearYearYear1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20Existing Heating System Operating CostsExisting Heating Oil Consumption$6.004,000gal$24,000$25,200$26,460$27,783$29,172$30,631$32,162$33,770$35,459$37,232$39,093$41,048$43,101$45,256$47,518$49,894$52,389$55,008$57,759$60,647Biomass System Operating CostsWood Fuel (Delivered to site)$330.0050%17.9cord($5,907)($6,084)($6,267)($6,455)($6,648)($6,848)($7,053)($7,265)($7,483)($7,707)($7,939)($8,177)($8,422)($8,675)($8,935)($9,203)($9,479)($9,763)($10,056)($10,358)Fossil Fuel$6.0050%2,000gal($12,000)($12,600)($13,230)($13,892)($14,586)($15,315)($16,081)($16,885)($17,729)($18,616)($19,547)($20,524)($21,550)($22,628)($23,759)($24,947)($26,194)($27,504)($28,879)($30,323)Electricity$0.000kWh$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0Operation and Maintenance Costs($50)($51)($52)($53)($54)($55)($56)($57)($59)($60)($61)($62)($63)($65)($66)($67)($69)($70)($71)($73)Additional Operation and Maintenance Costs for first 2 years($50)($51)$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0Total Operating Costs($18,007)($18,786)($19,549)($20,399)($21,289)($22,218)($23,191)($24,208)($25,271)($26,383)($27,546)($28,763)($30,036)($31,367)($32,760)($34,217)($35,742)($37,338)($39,007)($40,754)Annual Operating Cost Savings$5,993 $6,414 $6,911 $7,384 $7,884 $8,412 $8,972 $9,563 $10,188 $10,849 $11,547 $12,285 $13,065 $13,888 $14,758 $15,677 $16,647 $17,671 $18,752 $19,893Accumulated Cash Flow$5,993 $12,407 $19,318 $26,702 $34,585 $42,998 $51,969 $61,532 $71,720 $82,569 $94,116 $106,402 $119,466 $133,355 $148,113 $163,790 $180,437 $198,108 $216,860 $236,752Net Present Value($19,956) ($13,910) ($7,585) ($1,025)$5,776 $12,821 $20,116 $27,665 $35,473 $43,545 $51,887 $60,504 $69,401 $78,583 $88,055 $97,825 $107,896 $118,276 $128,970 $139,984Energy UnitsEconomic Analysis ResultsInflation RatesDescription Unit CostHeating Source ProportionAnnual Energy Units
Clarks Point - CPVC OfficeClarks Point, AlaskaProject Capital Cost($12,887)Simple Payback = Total Project Cost / First Year Cost Savings4.3 yearsPresent Value of Project Benefits (20 year life)$281,440Present Value of Operating Costs (20 year life)($198,732)Benefit / Cost Ratio of Project (20 year life)6.42Net Present Value (20 year life)$69,821Year Accumulated Cash Flow is Net PositiveFirst YearYear Accumulated Cash Flow > Project Capital Cost3.9 yearsDiscount Rate for Net Present Value Analysis3%Wood Fuel Escalation Rate3%Fossil Fuel Escalation Rate5%Electricity Escalation Rate3%O&M Escalation Rate2%YearYearYearYearYearYearYearYearYearYearYearYearYearYearYearYearYearYearYearYear1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20Existing Heating System Operating CostsExisting Heating Oil Consumption$6.002,000gal$12,000$12,600$13,230$13,892$14,586$15,315$16,081$16,885$17,729$18,616$19,547$20,524$21,550$22,628$23,759$24,947$26,194$27,504$28,879$30,323Biomass System Operating CostsWood Fuel (Delivered to site)$330.0050%8.9cord($2,937)($3,025)($3,116)($3,209)($3,306)($3,405)($3,507)($3,612)($3,721)($3,832)($3,947)($4,065)($4,187)($4,313)($4,442)($4,576)($4,713)($4,854)($5,000)($5,150)Fossil Fuel$6.0050%1,000gal($6,000)($6,300)($6,615)($6,946)($7,293)($7,658)($8,041)($8,443)($8,865)($9,308)($9,773)($10,262)($10,775)($11,314)($11,880)($12,474)($13,097)($13,752)($14,440)($15,162)Electricity$0.000kWh$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0Operation and Maintenance Costs($50)($51)($52)($53)($54)($55)($56)($57)($59)($60)($61)($62)($63)($65)($66)($67)($69)($70)($71)($73)Additional Operation and Maintenance Costs for first 2 years($50)($51)$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0Total Operating Costs($9,037)($9,427)($9,783)($10,208)($10,653)($11,118)($11,604)($12,112)($12,644)($13,200)($13,781)($14,390)($15,026)($15,692)($16,388)($17,117)($17,879)($18,677)($19,511)($20,385)Annual Operating Cost Savings$2,963 $3,173 $3,447 $3,683 $3,933 $4,198 $4,477 $4,773 $5,086 $5,416 $5,765 $6,134 $6,524 $6,936 $7,371 $7,831 $8,316 $8,828 $9,368 $9,939Accumulated Cash Flow$2,963 $6,136 $9,583 $13,266 $17,200 $21,397 $25,875 $30,648 $35,733 $41,149 $46,915 $53,049 $59,573 $66,510 $73,881 $81,711 $90,027 $98,854 $108,223 $118,162Net Present Value($10,010) ($7,020) ($3,865) ($592)$2,801 $6,316 $9,957 $13,724 $17,622 $21,652 $25,817 $30,120 $34,562 $39,148 $43,879 $48,759 $53,790 $58,975 $64,318 $69,821Energy UnitsEconomic Analysis ResultsInflation RatesDescription Unit CostHeating Source ProportionAnnual Energy Units
Clarks Point - Water Treatment PlantClarks Point, AlaskaProject Capital Cost($193,754)Simple Payback = Total Project Cost / First Year Cost Savings46.3 yearsPresent Value of Project Benefits (20 year life)$281,440Present Value of Operating Costs (20 year life)($149,444)Benefit / Cost Ratio of Project (20 year life)0.68Net Present Value (20 year life)($61,758)Year Accumulated Cash Flow is Net PositiveFirst YearYear Accumulated Cash Flow > Project Capital Cost>20 yearsDiscount Rate for Net Present Value Analysis3%Wood Fuel Escalation Rate3%Fossil Fuel Escalation Rate5%Electricity Escalation Rate3%O&M Escalation Rate2%YearYearYearYearYearYearYearYearYearYearYearYearYearYearYearYearYearYearYearYear1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20Existing Heating System Operating CostsExisting Heating Oil Consumption$6.002,000gal$12,000$12,600$13,230$13,892$14,586$15,315$16,081$16,885$17,729$18,616$19,547$20,524$21,550$22,628$23,759$24,947$26,194$27,504$28,879$30,323Biomass System Operating CostsWood Fuel (Delivered to site)$330.0085%15.2cord($5,016)($5,166)($5,321)($5,481)($5,646)($5,815)($5,989)($6,169)($6,354)($6,545)($6,741)($6,943)($7,152)($7,366)($7,587)($7,815)($8,049)($8,291)($8,539)($8,796)Fossil Fuel$6.0015%300gal($1,800)($1,890)($1,985)($2,084)($2,188)($2,297)($2,412)($2,533)($2,659)($2,792)($2,932)($3,079)($3,233)($3,394)($3,564)($3,742)($3,929)($4,126)($4,332)($4,549)Electricity$0.002,190kWh$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0Operation and Maintenance Costs($500)($510)($520)($531)($541)($552)($563)($574)($586)($598)($609)($622)($634)($647)($660)($673)($686)($700)($714)($728)Additional Operation and Maintenance Costs for first 2 years($500)($510)$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0Total Operating Costs($7,816)($8,076)($7,826)($8,095)($8,375)($8,664)($8,965)($9,276)($9,599)($9,935)($10,283)($10,644)($11,018)($11,407)($11,811)($12,230)($12,665)($13,116)($13,585)($14,073)Annual Operating Cost Savings$4,184 $4,524 $5,404 $5,796 $6,211 $6,651 $7,117 $7,609 $8,130 $8,681 $9,264 $9,880 $10,532 $11,221 $11,948 $12,717 $13,530 $14,388 $15,294 $16,251Accumulated Cash Flow$4,184 $8,708 $14,111 $19,907 $26,119 $32,770 $39,886 $47,495 $55,626 $64,307 $73,571 $83,451 $93,983 $105,204 $117,152 $129,870 $143,400 $157,787 $173,081 $189,332Net Present Value($189,692) ($185,428) ($180,483) ($175,333) ($169,975) ($164,405) ($158,618) ($152,612) ($146,381) ($139,921) ($133,228) ($126,299) ($119,127) ($111,709) ($104,039) ($96,114) ($87,929) ($79,477) ($70,755) ($61,758)Energy UnitsHeating Source ProportionEconomic Analysis ResultsInflation RatesDescription Unit CostAnnual Energy Units
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc.
Appendix C
Site Plan
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc.
Site Plan of Clark’s Point Lower Village
Community Center
CPVC Office
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc.
Site Plan of Clark’s Point Upper Village
City Office
Post Office
Clinic
Water
Treatment
Plant
Feasibility Assessment for Biomass Heating Systems Clark’s Point, AK
Coffman Engineers, Inc.
Appendix D
AWEDTG Field Data Sheet