HomeMy WebLinkAboutMinto Village Council Wood Fired Heating Systems Final Report 07-24-2012-BIO
Pre-Feasibility Assessment for
Integration of Wood-Fired Heating Systems
Final Report
July 24, 2012
Minto Village Council
Minto, Alaska
Presented by
CTA Architects Engineers
Nick Salmon & Nathan Ratz
Lars Construction Management Services
Rex Goolsby
For
Minto Village Council
In partnership with
Fairbanks Economic Development Corporation
Alaska Wood Energy Development Task Group
Funded by
Alaska Energy Authority and US Forest Service
306 W. Railroad, Suite 104
Missoula, MT 59802
406.728.9522
www.ctagroup.com
CTA Project: FEDC_FAIRBANKS_MINTO
Pre-Feasibility Assessment for Minto Village Council
Integration of Wood-Fired Heating Systems Minto, Alaska
CTA Architects Engineers i
July 24, 2012
TABLE OF CONTENTS
1.0 Executive Summary ................................................................................................... 1
2.0 Introduction ............................................................................................................... 3
3.0 Existing Building Systems.......................................................................................... 3
4.0 Energy Use ............................................................................................................... 4
5.0 Biomass Boiler Size ................................................................................................... 4
6.0 Wood Fuel Use .......................................................................................................... 5
7.0 Boiler Plant Location and Site Access ....................................................................... 6
8.0 Integration with Existing Heating Systems ................................................................. 7
9.0 Air Quality Permits ..................................................................................................... 7
10.0 Wood Heating Options .............................................................................................. 7
11.0 Estimated Costs ........................................................................................................ 8
12.0 Economic Analysis Assumptions ............................................................................... 8
13.0 Results of Evaluation ................................................................................................. 8
14.0 Project Funding ......................................................................................................... 9
15.0 Summary ................................................................................................................... 9
16.0 Recommended Action ............................................................................................... 9
Appendixes
Appendix A: Preliminary Estimates of Probable Cost ................................................ 2 pages
Appendix B: Cash Flow Analysis ............................................................................... 4 pages
Appendix C: Site Plan ............................................................................................... 2 pages
Appendix D: Air Quality Report ............................................................................... 10 pages
Appendix E: Wood Fired Heating Technologies ........................................................ 3 pages
Pre-Feasibility Assessment for Minto Village Council
Integration of Wood-Fired Heating Systems Minto, Alaska
CTA Architects Engineers Page 1 of 9
July 24, 2012
1.0 Executive Summary
The following assessment was commissioned to determine the preliminary technical and
economic feasibility of integrating a wood fired heating system in the Lakeview Lodge, the
Health Center, the Community Hall, and a future Fire Station in Minto, Alaska.
The following tables summarize the current fuel use and the potential wood fuel use:
Table 1.1 - Annual Fuel Use Summary
Fuel Avg. Use Current Annual
Facility Name Type (Gallons) Cost $/Gal Cost
Lakeview Lodge Fuel Oil 10,000 $5.65 $56,500
Community Hall Fuel Oil 950 $5.65 $5,368
Future Fire Station None - - -
Medical Clinic Fuel Oil 1,400 $5.65 $7,910
Table 1. 2 - Annual Wood Fuel Use Summary
Fuel Cord Wood
Oil Wood Pellets
(Gallons) (Cords) (Tons)
Lakeview Lodge (LL) 10,000 87.4 79.7
Health Clinic (HC) 1,400 12.2 11.2
Community Center (CC) 950 8.3 7.6
Future Fire Department (FD) 1,250 10.9 10.0
LL + HC 11,400 99.6 90.8
Note: Wood fuel use assumes offsetting 85% of the current energy use.
Based on the potential wood use both pellet boiler and cord wood boiler options were
investigated and were as follows:
Wood Pellet Boiler Options:
B.1: Lakeview Lodge and Health Center.
Cord Wood Boiler Options:
C.1: Lakeview Lodge.
C.2: Lakeview Lodge and Health Center.
The table on the following page summarizes the economic evaluation for each option:
CTA Architects Engineers Page 2 of 9
July 24, 2012
Table 1.3 - Economic Evaluation Summary
Minto Biomass Heating System
Year 1 NPV NPV
20
Yr
30
Yr
Project Operating 30 yr 20 yr B/C B/C ACF ACF YR
Cost Savings at 3% at 3% Ratio Ratio YR 20 YR 30 ACF=PC
B.1 $670,000 $5,199 $579,979 $286,108 0.43 0.87 $420,716 $1,053,449 25
C.1 $298,000 $17,176 $1,054,942 $571,617 1.92 3.54 $823,607 $1,862,159 11
C.2 $325,000 $21,463 $1,246,405 $682,006 2.10 3.84 $980,472 $2,192,971 10
The Lakeview Lodge combined with the Health Center appears to be a good candidate for
the use of a wood biomass heating system. With the current economic assumptions, the
estimated fuel use, and the reported fuel oil prices, this option has a very strong 20 year
B/C ratio of 2.1. It is an increased benefit to add the health center to the lodge project
even with the additional piping and pumping costs.
Additional sensitivity analysis has been performed. The sensitivity was performed on
option C.2, with the cost of fuel oil being varied as well as varying the cost of wood fuel.
With cord wood at $200/cord, the 20 year B/C exceeds 1.0 at $4.10/gallon for fuel oil.
With cord wood at $150/cord, the 20 year B/C exceeds 1.0 at $3.70/gallon for fuel oil.
Pre-Feasibility Assessment for Minto Village Council
Integration of Wood-Fired Heating Systems Minto, Alaska
CTA Architects Engineers Page 3 of 9
July 24, 2012
2.0 Introduction
The following assessment was commissioned to determine the preliminary technical and
economic feasibility of integrating a wood fired heating system in the Lakeview Lodge, the
Health Center, the Community Hall, and a future Fire Station in Minto, Alaska.
3.0 Existing Building Systems
The buildings are all owned and operated by the Minto Village Council. The buildings are
all located in the town of Minto.
The Lakeview Lodge is a two story wood framed building constructed in approximately
1982. The facility is approximately 11,300 square feet and is heated by a 348,000 Btu/hr
output hot water boiler. Domestic hot water is provided by a 170,000 Btu/hr fuel oil fired
hot water heater with a 70 gallon tank. The existing boiler is original to the building and is
in fair condition. The heating system infrastructure is original to the building an in fair
condition. The building envelop is in poor condition.
The Minto Community Hall is an 8-inch log building with some wood framed walls
constructed in 2005. The facility is approximately 6,300 square feet and is heated by a
175,000 Btu/hr output hot water boiler and by a cord wood stove capable of receiving 4-
foot length logs. The cord wood stove serves the large community room. The boiler heats
the toilet rooms, the small kitchen, and some storage rooms at the entry. There is also a
unit heater connected to the boiler system that heats the large community room, but it is
valved off and the community room is currently unheated unless there is an event. Only
approximately 1,700 square feet of the building is heated with the boiler system. Domestic
hot water is provided by an electric water heater rated at 4.5 KW input with 40 gallon
storage. The existing boiler is original to the building and is in good condition. The
heating system infrastructure is original to the building and in good condition.
The future Fire Station is proposed to be located in an existing building next to the water
plant. This existing building is a wood framed building approximately 5,000 square feet.
The building is currently not heated and the boiler has been removed from the building.
Portions of the building are abandoned and in disrepair, other portions are used for
unheated storage, and the two bay garage on the west side is used by the Village Council
for some vehicle maintenance. This two bay garage area and some of the adjacent rooms
are proposed to be remodeled and used for the future fire station. There is no domestic
hot water in the building.
Facilities Dropped from Feasibility Study
No facilities were dropped from the feasibility study.
Facilities Added to Feasibility Study
The Health Center was added to the feasibility study during the field visit. The clinic is a
wood framed building constructed in approximately 2005 and located next to Lakeview
Lodge. The facility is approximately 2,000 square feet and is heated by a 115,000 Btu/hr
output hot water boiler. Domestic hot water is provided by a 40 gallon indirect water
heater using the boiler water as a heating source. The existing boiler is original to the
building and is in good condition. The heating system infrastructure is original to the
building an in good condition.
Pre-Feasibility Assessment for Minto Village Council
Integration of Wood-Fired Heating Systems Minto, Alaska
CTA Architects Engineers Page 4 of 9
July 24, 2012
4.0 Energy Use
The Minto Village Council purchases fuel oil in bulk and fills storage tanks which are then
used to provide fuel to MVC vehicles, equipment, and building heat. The amount of fuel
used at each building for heating is not currently tracked. The Village Council has
estimated that 12,000 gallons is used for building heat at their facilities. CTA has
estimated the potential fuel use at each building based on square footage and estimated
heating energy use index. The following table summarizes the data:
Table 4.1 - Annual Fuel Use Summary
Fuel Avg. Use Current Annual
Facility Name Type (Gallons) Cost $/Gal Cost
Lakeview Lodge Fuel Oil 10,000 $5.65 $56,500
Community Hall Fuel Oil 950 $5.65 $5,368
Future Fire Station None - - -
Medical Clinic Fuel Oil 1,400 $5.65 $7,910
Electrical energy consumption will increase with the installation of a wood fired boiler
system because of the power needed for the biomass boiler components such as draft
fans and the additional pumps needed to integrate into the existing heating systems. The
cash flow analysis accounts for the additional electrical energy consumption and reduces
the annual savings accordingly.
5.0 Biomass Boiler Size
The following table summarized the connected load of fuel fired boiler:
Table 5.1 - Connected Boiler Load Summary
Likely
Peak System
Output Load Peak
MBH Factor MBH
Lakeview Lodge Boiler Fuel Oil 348 1.00 348
Minto Health Clinic Boiler Fuel Oil 115 1.00 115
Community Center Boiler Fuel Oil 175 1.00 175
Future Fire Dept. Boiler Fuel Oil 150 1.00 150
Total Of All Buildings 788 788
Pre-Feasibility Assessment for Minto Village Council
Integration of Wood-Fired Heating Systems Minto, Alaska
CTA Architects Engineers Page 5 of 9
July 24, 2012
Typically a wood heating system is sized to meet approximately 85% of the typical annual
heating energy use of the building. The existing heating systems would be used for the
remaining 15% of the time during peak heating conditions, during times when the biomass
heating system is down for servicing, and during swing months when only a few hours of
heating each day are required. Recent energy models have found that a boiler sized at
50% to 60% of the building peak load will typically accommodate 85% of the boiler run
hours. Because of the small scale of the heating system, the output will be based on the
smallest cordwood boiler size available, or approximately 170,000 Btu/hr.
Table 5.2 - Proposed Biomass Boiler Size
Likely Biomass
System Biomass Boiler
Peak Boiler Size
MBH Factor MBH
Lakeview Lodge (LL) 348 0.6 209
Health Center (HC) 115 0.6 69
Community Center (CC) 175 0.6 105
Future Fire Dept (FD) 150 0.6 90
LL + HC 463 0.6 278
The buildings are too far apart to consider a district heating system to connect all of them
together. The Lakeview Lodge and the Health Center could be fed from a single boiler
plant because they are adjacent to each other.
6.0 Wood Fuel Use
The types of fuel available in the area include cord wood and wood pellets. The estimated
amount of wood fuel needed for each wood fuel type for each building was calculated and
is listed below:
Table 6.1 - Annual Wood Fuel Use Summary
Fuel Cord Wood
Oil Wood Pellets
(Gallons) (Cords) (Tons)
Lakeview Lodge (LL) 10,000 87.4 79.7
Health Clinic (HC) 1,400 12.2 11.2
Community Center (CC) 950 8.3 7.6
Future Fire Department (FD) 1,250 10.9 10.0
LL + HC 11,400 99.6 90.8
Note: Wood fuel use assumes offsetting 85% of the current energy use.
The amount of wood fuels shown in the table is for offsetting 85% of the total fuel oil use.
Pre-Feasibility Assessment for Minto Village Council
Integration of Wood-Fired Heating Systems Minto, Alaska
CTA Architects Engineers Page 6 of 9
July 24, 2012
The moisture content of the wood fuels and the overall wood burning system efficiencies
were accounted for in these calculations. The existing fuel oil boilers were assumed to be
80% efficient. Cord wood was assumed to be 20% moisture content (MC) with a system
efficiency of 65%. Wood pellets were assumed to be 7% MC with a system efficiency of
70%
Based on the potential wood fuel use, cord wood and pellet boiler systems were analyzed
for the Lakeview Lodge and the Health Center. The low potential wood fuel use makes a
chip system not practical and no chip options will be reviewed. The low potential wood
use and low potential savings for the Community Center and the future Fire Department
makes those challenged projects and they will not be analyzed further.
The tribe and village corporation own over 80,000 acres of land, of which most of it is
forested. There would be a sufficient supply to support a wood fired boiler for this campus.
The tribe and village corporation do not currently have any active logging operations, but
there are several local independent contractors that harvest firewood. Wood pellets are
available from Superior Pellet Fuels out of North Pole and can be trucked own the Elliot
Highway.
The unit fuel costs for fuel oil and the different fuel types were calculated and equalized to
dollars per million Btu ($/MMBtu) to allow for direct comparison. The Delivered $/MMBtu
is the cost of the fuel based on what is actually delivered to the heating system, which
includes all the inefficiencies of the different systems. The Gross $/MMBtu is the cost of
the fuel based on raw fuel, or the higher heating value and does not account for any
system inefficiencies. The following table summarizes the equalized fuel costs at different
fuel unit costs:
Table 6.2 - Unit Fuel Costs Equalized to $/MMBtu
Net
Gross System System
Delivered Gross
Fuel Type Units Btu/unit Efficiency Btu/unit $/unit $/MMBtu $/MMBtu
Fuel Oil gal 134500 0.8 107600 $4.00 $37.17 $29.74
$5.00 $46.47 $37.17
$6.00 $55.76 $44.61
Cord Wood cords 16173800 0.65 10512970 $200.00 $19.02 $12.37
$250.00 $23.78 $15.46
$300.00 $28.54 $18.55
Pellets tons 16400000 0.7 11480000 $300.00 $26.13 $18.29
$350.00 $30.49 $21.34
$400.00 $34.84 $24.39
7.0 Boiler Plant Location and Site Access
None of the existing boiler rooms are large enough to fit a new biomass boiler so a new
stand alone boiler plant would be required. The best location for a plant would be just
west of the Lakeview Lodge, between the lodge and the health center.
Pre-Feasibility Assessment for Minto Village Council
Integration of Wood-Fired Heating Systems Minto, Alaska
CTA Architects Engineers Page 7 of 9
July 24, 2012
Any type of biomass boiler system will require access by delivery vehicles. For cord wood
systems this would likely be pick up trucks and trucks with trailers. For pellet systems, this
would likely require large delivery vehicles such as 40 foot long trailers. The proposed
plant location would allow for good access since it will be just off a wide road (Lakeview
Road) and will allow for tractor trailers to maneuver. Minto connects to the Elliot Highway
via Minto road and this road can handle the large truck traffic.
8.0 Integration with Existing Heating Systems
Integration of a wood fired heating system varies from facility to facility. Integration of a
central heating system in the Lakeview Lodge would require piping heating hot water
supply and return lines to the existing boiler room.
Integration of a central heating system in the Health Center would require the installation
of heating hot water supply and return pipes in the existing boiler room.
The Minto Community Hall is not an obvious candidate for another wood fired heating
system in addition to the existing wood stove.
The future Fire Station is not an obvious candidate for a wood fired heating system.
The field visit confirmed the location of each boiler room and heating unit location in order
to identify an approximate point of connection from a district heating loop to each existing
building. Connections would typically be achieved with arctic pipe extended to the face of
each building, and extended up the exterior surface of the building in order to penetrate
exterior wall into the boiler room or building. Once the heating water supply and return
piping enters the existing boiler room it would be connected to existing supply and return
lines in appropriate locations in order to utilize existing pumping systems within each
building.
9.0 Air Quality Permits
Resource System Group has done a preliminary review of potential air quality issues in the
area. Interior Alaska is prone to meteorological conditions that create thermal inversions,
which are unfavorable for the dispersion of emissions. The proposed boiler size at this
location is small enough, that the boiler is not likely to require any State or Federal permits.
See air quality memo in appendix D.
10.0 Wood Heating Options
The technologies available to produce heating energy from wood based biomass are
varied in their approach, but largely can be separated into three types of heating plants:
cord wood, wood pellet and wood chip/ground wood fueled. See Appendix E for these
summaries.
Based on the potential wood use both pellet boiler and cord wood boiler options were
investigated and were as follows:
Wood Pellet Boiler Options:
B.1: Lakeview Lodge and Health Center.
Cord Wood Boiler Options:
C.1: Lakeview Lodge.
Pre-Feasibility Assessment for Minto Village Council
Integration of Wood-Fired Heating Systems Minto, Alaska
CTA Architects Engineers Page 8 of 9
July 24, 2012
C.2: Lakeview Lodge and Health Center.
Option B.1 would be installed in a freestanding building and an adjacent free standing
pellet silo. Option C.1 would be installed in a freestanding building with interior cordwood
fuel storage.
11.0 Estimated Costs
The total project costs are at a preliminary design level and are based on RS Means and
recent biomass project bid data. The estimates are shown in the appendix. These costs
are conservative and if a deeper level feasibility analysis is undertaken and/or further
design occurs, the costs may be able to be reduced.
12.0 Economic Analysis Assumptions
The cash flow analysis assumes fuel oil at $5.65/gal, electricity at $0.65/kwh, cord wood
delivered at $200/ton, and pellets delivered at $375/ton. The fuel oil, electricity, and cord
wood costs are based on the costs reported by the facility. Pellet costs were obtained
from Superior Pellet Fuels. It is assumed that the wood boiler would supplant 85% of the
estimated heating use, and the existing heating systems would heat the remaining 15%.
Each option assumes the total project can be funded with grants and non obligated capital
money. The following inflation rates were used: O&M - 2%, Fossil Fuel – 5%, Wood Fuel
– 3%, Discount Rate for NPV calculation – 3%. The fossil fuel inflation rate is based on
the DOE EIA website. DOE is projecting a slight plateau with a long term inflation of
approximately 5%. As a point of comparison, oil prices have increased at an annual rate
of over 8% since 2001.
The analysis also accounts for additional electrical energy required for the wood f ired
boiler system as well as the system pumps to distribute heating hot water to the buildings.
Wood fired boiler systems also will require more maintenance, and these additional
maintenance costs are also factored into the analysis.
13.0 Results of Evaluation
The following table summarizes the economic evaluation for each option:
Table 13.1 - Economic Evaluation Summary
Minto Biomass Heating System
Year 1 NPV NPV
20
Yr
30
Yr
Project Operating 30 yr 20 yr B/C B/C ACF ACF YR
Cost Savings at 3% at 3% Ratio Ratio YR 20 YR 30 ACF=PC
B.1 $670,000 $5,199 $579,979 $286,108 0.43 0.87 $420,716 $1,053,449 25
C.1 $298,000 $17,176 $1,054,942 $571,617 1.92 3.54 $823,607 $1,862,159 11
C.2 $325,000 $21,463 $1,246,405 $682,006 2.10 3.84 $980,472 $2,192,971 10
The benefit to cost ration (B/C) takes the net present value (NPV) of the net energy
savings and divides it by the construction cost of the project. A B/C ratio greater than or
equal to 1.0 indicates an economically advantageous project.
Pre-Feasibility Assessment for Minto Village Council
Integration of Wood-Fired Heating Systems Minto, Alaska
CTA Architects Engineers Page 9 of 9
July 24, 2012
Accumulated cash flow (ACF) is another evaluation measure that is calculated in this
report and is similar to simple payback with the exception that accumulated cash flow
takes the cost of financing and fuel escalation into account. For many building owners,
having the accumulated cash flow equal the project cost within 15 years is considered
necessary for implementation. If the accumulated cash flow equals project cost in 20
years or more, that indicates a challenged project. Positive accumulated cash flow should
also be considered an avoided cost as opposed to a pure savings.
14.0 Project Funding
The Minto Village Tribal Council may pursue a biomass project grant from the Alaska
Energy Authority.
The Minto Village Tribal Council could also enter into a performance contract for the
project. Companies such as Siemens, McKinstry, Johnson Controls and Chevron have
expressed an interest in participating in funding projects of all sizes throughout Alaska.
This allows the facility owner to pay for the project entirely from the guaranteed energy
savings, and to minimize the project funds required to initiate the project. The scope of the
project may be expanded to include additional energy conservation measures.
15.0 Summary
The Lakeview Lodge combined with the Health Center appears to be a good candidate for
the use of a wood biomass heating system. With the current economic assumptions, the
estimated fuel use, and the reported fuel oil prices, this option has a very strong 20 year
B/C ratio of 2.1. It is an increased benefit to add the health center to the lodge project
even with the additional piping and pumping costs.
Additional sensitivity analysis has been performed and is attached. The sensitivity was
performed on option C.2, with the cost of fuel oil being varied as well as varying the cost of
wood fuel. With cord wood at $200/cord, the 20 year B/C exceeds 1.0 at $4.10/gallon for
fuel oil. With cord wood at $150/cord, the 20 year B/C exceeds 1.0 at $3.70/gallon for fuel
oil. This indicates that this is still an economically viable project with fuel oil around
$4.00/gallon.
16.0 Recommended Action
Most grant programs will likely require a full feasibility assessment. A full assessment
would provide more detail on the air quality issues, wood fuel resources, and a schematic
design of the boiler systems and system integration to obtain more accurate costs.
It is also recommended to measure and track the amount of fuel oil used by the lodge and
health center to validate the usage assumptions of this report. A detailed energy analysis
could also be performed to better estimate the usage, however, actual measured fuel oil
use is the best since it is actual usage.
APPENDIX A
Preliminary Estimates of Probable Cost
Preliminary Estimates of Probable Cost
Biomass Heating Options
Minto, AK
Pellet Option B.1 - Lakeview Lodge + Health Center
Biomass Boiler Building:$90,000
Wood Heating, Wood Handling System, & Pellet Silo: $140,000
Stack/Air Pollution Control Device:$50,000
Mechanical/Electrical within Boiler Building: $75,000
Underground Piping $18,000
Lakeview Lodge Integration $9,500
Health Clinic Integration $7,200
Subtotal:$389,700
30% Remote Factor $116,910
Subtotal:$506,610
Design Fees, Building Permit, Miscellaneous Expenses 15%: $75,992
Subtotal:$582,602
15% Contingency:$87,390
Subtotal:669,992$
Total Project Costs $669,992
Preliminary Estimates of Probable Cost
Biomass Heating Options
Minto, AK
Cord Wood Option C.1 - Lakeview Lodge
Cord Wood Storage/ Boiler Building: $97,500
Wood Heating Boiler:$32,000
Stack:$4,400
Mechanical/Electrical within Boiler Building: $20,200
Underground Piping $10,000
Lakeview Lodge Integration $9,500
Subtotal:$173,600
30% Remote Factor $52,080
Subtotal:$225,680
Design Fees, Building Permit, Miscellaneous Expenses 15%: $33,852
Subtotal:$259,532
15% Contingency:$38,930
Subtotal:298,462$
Total Project Costs $298,462
Cord Wood Option C.2 - Lakeview Lodge + Health Center
Cord Wood Storage/ Boiler Building: $97,500
Wood Heating Boiler:$32,000
Stack:$4,400
Mechanical/Electrical within Boiler Building: $20,200
Underground Piping $18,000
Lakeview Lodge Integration $9,500
Health Clinic Integration $7,200
Subtotal:$188,800
30% Remote Factor $56,640
Subtotal:$245,440
Design Fees, Building Permit, Miscellaneous Expenses 15%: $36,816
Subtotal:$282,256
15% Contingency:$42,338
Subtotal:324,594$
Total Project Costs $324,594
APPENDIX B
Cash Flow Analysis
&
Economic Sensitivity Analysis
Lakeview LodgeOption B.1Minto, AlaskaWood Pellet Boiler Date: July 24, 2012 Analyst: CTA Architects Engineers - Nick Salmon & Nathan Ratz EXISTING CONDITIONSLakeview LdgTotalExisting Fuel Type:Fuel Oil Fuel Oil Fuel Oil Fuel OilFuel Units:gal gal gal galCurrent Fuel Unit Cost:$5.65 $5.65 $5.65 $5.65 Estimated Average Annual Fuel Usage:10,00010,000Annual Heating Costs:$56,500 $0 $0 $0 $56,500ENERGY CONVERSION (to 1,000,000 Btu; or 1 dkt)Fuel Heating Value (Btu/unit of fuel):134500 134500 134500 134500Current Annual Fuel Volume (Btu):1,345,000,000 0 0 0Assumed efficiency of existing heating system (%):80% 80% 80% 80% Net Annual Energy Produced (Btu):1,076,000,000 0 0 0 1,076,000,000WOOD FUEL COSTWood Pellets$/ton: $375.00Assumed efficiency of wood heating system (%): 70% PROJECTED WOOD FUEL USAGEEstimated Btu content of wood fuel (Btu/lb) - Assumed 7% MC 8200 Tons of wood fuel to supplant net equivalent of 100% annual heating load.94Tons of wood fuel to supplant net equivalent of 85% annual heating load.8025 ton chip van loads to supplant net equivalent of 85% annual heating load.3 Project Capital Cost-$670,000 Project Financing InformationPercent Financed0.0%Est. Pwr Use 15000 kWh Type Hr/Wk Wk/Yr Total Hr Wage/Hr TotalAmount Financed$0 Elec Rate $0.650 /kWh Biomass System 2.0 40 80 $20.00 $1,600Amount of Grants$670,000 Other 0.0 40 0 $20.00 $01st 2 Year Learning 2.0 40 80 $20.00 $1,600Interest Rate5.00%Term10Annual Finance Cost (years)$0 128.9 years Net Benefit B/C Ratio$579,979 -$90,021 0.87$286,108 -$383,8920.43Year Accumulated Cash Flow > 0#N/AYear Accumulated Cash Flow > Project Capital Cost25Inflation FactorsO&M Inflation Rate2.0%Fossil Fuel Inflation Rate5.0%Wood Fuel Inflation Rate3.0%Electricity Inflation Rate5.0%Discount Rate for Net Present Value Calculation 3.0%Year Year Year Year Year Year Year Year Year Year Year Year Year Year Year Year Year YearCash flow Descriptions Unit Costs HeatingSource ProportionAnnual Heating Source VolumesHeating Units 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 20 25 30Existing Heating System Operating CostsDisplaced heating costs $5.65 10000 gal $56,500 $59,325 $62,291 $65,406 $68,676 $72,110 $75,715 $79,501 $83,476 $87,650 $92,033 $96,634 $101,466 $106,539 $111,866 $142,773 $182,218 $232,562Displaced heating costs $5.650 gal $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0Displaced heating costs $5.650 gal $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0Displaced heating costs $5.650 gal $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0Biomass System Operating CostsWood Fuel ($/ton, delivered to boiler site)$375.00 85% 80 tons $29,876 $30,772 $31,695 $32,646 $33,626$34,634 $35,673 $36,744 $37,846 $38,981 $40,151 $41,355 $42,596 $43,874 $45,190 $52,388 $60,731 $70,404Small load existing fuel$5.65 15% 1500 gal $8,475 $8,899 $9,344 $9,811 $10,301 $10,816 $11,357 $11,925 $12,521 $13,148 $13,805 $14,495 $15,220$15,981 $16,780 $21,416 $27,333 $34,884Small load existing fuel$5.65 15% 0 gal $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0Small load existing fuel$5.65 15% 0 gal $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0Small load existing fuel$5.65 15% 0 gal $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0Additional Operation and Maintenance Costs$1,600 $1,632 $1,665 $1,698 $1,732 $1,767 $1,802 $1,838 $1,875 $1,912 $1,950 $1,989 $2,029 $2,070 $2,111 $2,331 $2,573$2,841Additional Operation and Maintenance Costs First 2 years$1,600 $1,632Additional Electrical Cost $0.650$9,750 $10,238 $10,749 $11,287 $11,851 $12,444 $13,066 $13,719 $14,405 $15,125 $15,882 $16,676 $17,510 $18,385 $19,304 $24,638 $31,445 $40,132Annual Operating Cost Savings$5,199$6,153$8,838$9,964$11,166$12,449$13,817$15,275$16,829$18,484$20,245$22,119$24,111$26,230$28,481$42,001$60,136$84,299Financed Project Costs - Principal and Interest0000000000 Displaced System Replacement Costs (year one only)0Net Annual Cash Flow5,199 6,153 8,838 9,964 11,166 12,449 13,817 15,275 16,829 18,484 20,245 22,119 24,111 26,230 28,481 42,001 60,136 84,299Accumulated Cash Flow5,199 11,352 20,190 30,154 41,320 53,769 67,586 82,861 99,690 118,174 138,419 160,537 184,649 210,879 239,359 420,716683,022 1,053,449Additional Power UseAdditional MaintenanceSimple Payback: Total Project Cost/Year One Operating Cost Savings:Net Present Value (30 year analysis):Net Present Value (20 year analysis):
Lakeview LodgeOption C.1Minto, AlaskaCord Wood Boiler Date: July 24, 2012 Analyst: CTA Architects Engineers - Nick Salmon & Nathan Ratz EXISTING CONDITIONSLakeview LdgTotalExisting Fuel Type:Fuel Oil Fuel Oil Fuel Oil Fuel OilFuel Units:gal gal gal galCurrent Fuel Unit Cost:$5.65 $5.65 $5.65 $5.65 Estimated Average Annual Fuel Usage:10,00010,000Annual Heating Costs:$56,500 $0$56,500ENERGY CONVERSION (to 1,000,000 Btu; or 1 dkt)Fuel Heating Value (Btu/unit of fuel):134500 134500 134500 134500Current Annual Fuel Volume (Btu):1,345,000,000 0 0 0Assumed efficiency of existing heating system (%):80% 80% 80% 80% Net Annual Energy Produced (Btu):1,076,000,000 0 0 0 1,076,000,000WOOD FUEL COSTCord Wood$/cord: $200.00Assumed efficiency of wood heating system (%): 65% PROJECTED WOOD FUEL USAGEEstimated Btu content of wood fuel (Btu/lb) - Assumed 20% MC, 6,700 Btu/lb x 28.4 lb/cf x 85 cf16,173,800 Cords of wood fuel to supplant net equivalent of 100% annual heating load.102.3Cords of wood fuel to supplant net equivalent of 85% annual heating load.87.025 ton chip van loads to supplant net equivalent of 85% annual heating load.N/A Project Capital Cost-$298,000 Project Financing InformationPercent Financed0.0%Est. Pwr Use 1000 kWh Type Hr/Wk Wk/Yr Total Hr Wage/Hr TotalAmount Financed$0 Elec Rate $0.650 /kWh Biomass System 14.0 40 560 $20.00 $11,200Amount of Grants$298,000 Other 0.0 40 0 $20.00 $01st 2 Year Learning 2.0 40 80 $20.00 $1,600Interest Rate5.00%Term10Annual Finance Cost (years)$0 17.4 years Net Benefit B/C Ratio$1,054,942 $756,942 3.54$571,617 $273,6171.92Year Accumulated Cash Flow > 0#N/AYear Accumulated Cash Flow > Project Capital Cost11Inflation FactorsO&M Inflation Rate2.0%Fossil Fuel Inflation Rate5.0%Wood Fuel Inflation Rate3.0%Electricity Inflation Rate5.0%Discount Rate for Net Present Value Calculation 3.0%Year Year Year Year Year Year Year Year Year Year Year Year Year Year Year Year Year YearCash flow Descriptions Unit Costs HeatingSource ProportionAnnual Heating Source VolumesHeating Units 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 20 25 30Existing Heating System Operating CostsDisplaced heating costs $5.65 10000 gal $56,500 $59,325 $62,291 $65,406 $68,676 $72,110 $75,715 $79,501 $83,476 $87,650 $92,033 $96,634 $101,466 $106,539 $111,866 $142,773 $182,218 $232,562Displaced heating costs $5.650 gal $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0Displaced heating costs $5.650 gal $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0Displaced heating costs $5.650 gal $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0Biomass System Operating CostsWood Fuel ($/ton, delivered to boiler site)$200.00 85% 87 cords $17,399 $17,921 $18,459 $19,013 $19,583 $20,171 $20,776 $21,399 $22,041 $22,702 $23,383 $24,085 $24,807 $25,552 $26,318 $30,510 $35,370 $41,003Small load existing fuel$5.65 15% 1500 gal $8,475 $8,899 $9,344 $9,811 $10,301 $10,816 $11,357 $11,925 $12,521 $13,148 $13,805 $14,495 $15,220$15,981 $16,780 $21,416 $27,333 $34,884Small load existing fuel$5.65 15% 0 gal $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0Small load existing fuel$5.65 15% 0 gal $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0Small load existing fuel$5.65 15% 0 gal $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0Additional Operation and Maintenance Costs$11,200 $11,424 $11,652 $11,886 $12,123 $12,366 $12,613 $12,865 $13,123 $13,385 $13,653 $13,926 $14,204 $14,488 $14,778 $16,316 $18,014 $19,889Additional Operation and Maintenance Costs First 2 years$1,600 $1,632Additional Electrical Cost $0.650$650 $683 $717 $752 $790 $830 $871 $915 $960 $1,008 $1,059 $1,112 $1,167 $1,226 $1,287 $1,643 $2,096 $2,675Annual Operating Cost Savings$17,176$18,766$22,119$23,944$25,878$27,927$30,098$32,397$34,831$37,407$40,133$43,017$46,067$49,293$52,703$72,888$99,405$134,109Financed Project Costs - Principal and Interest0000000000 Displaced System Replacement Costs (year one only)0Net Annual Cash Flow17,176 18,766 22,119 23,944 25,878 27,927 30,098 32,397 34,831 37,407 40,133 43,017 46,067 49,293 52,703 72,888 99,405134,109Accumulated Cash Flow17,176 35,942 58,061 82,005 107,883 135,811 165,909 198,306 233,137 270,543 310,676 353,693 399,760 449,052 501,755 823,607 1,264,728 1,862,159Additional Power UseAdditional MaintenanceSimple Payback: Total Project Cost/Year One Operating Cost Savings:Net Present Value (30 year analysis):Net Present Value (20 year analysis):
Lakeview Lodge and Health Center Option C.2Minto, AlaskaCord Wood Boiler Date: July 24, 2012 Analyst: CTA Architects Engineers - Nick Salmon & Nathan Ratz EXISTING CONDITIONSLakeview Ldg Health Cl.TotalExisting Fuel Type:Fuel Oil Fuel Oil Fuel Oil Fuel OilFuel Units:gal gal gal galCurrent Fuel Unit Cost:$5.65 $5.65 Estimated Average Annual Fuel Usage:10,000 1,40011,400Annual Heating Costs:$56,500 $7,910$64,410ENERGY CONVERSION (to 1,000,000 Btu; or 1 dkt)Fuel Heating Value (Btu/unit of fuel):134500 134500 134500 134500Current Annual Fuel Volume (Btu):1,345,000,000 188,300,000 0 0Assumed efficiency of existing heating system (%):80% 80% 80% 80% Net Annual Energy Produced (Btu):1,076,000,000 150,640,000 0 0 1,226,640,000WOOD FUEL COSTCord Wood$/cord: $200.00Assumed efficiency of wood heating system (%): 65% PROJECTED WOOD FUEL USAGEEstimated Btu content of wood fuel (Btu/lb) - Assumed 20% MC, 6,700 Btu/lb x 28.4 lb/cf x 85 cf16,173,800 Cords of wood fuel to supplant net equivalent of 100% annual heating load.116.7Cords of wood fuel to supplant net equivalent of 85% annual heating load.99.225 ton chip van loads to supplant net equivalent of 85% annual heating load.N/A Project Capital Cost-$325,000 Project Financing InformationPercent Financed0.0%Est. Pwr Use 1000 kWh Type Hr/Wk Wk/Yr Total Hr Wage/Hr TotalAmount Financed$0 Elec Rate $0.650 /kWh Biomass System 14.0 40 560 $20.00 $11,200Amount of Grants$325,000 Other 0.0 40 0 $20.00 $01st 2 Year Learning 2.0 40 80 $20.00 $1,600Interest Rate5.00%Term10Annual Finance Cost (years)$0 15.1 years Net Benefit B/C Ratio$1,246,405 $921,405 3.84$682,006 $357,0062.10Year Accumulated Cash Flow > 0#N/AYear Accumulated Cash Flow > Project Capital Cost10Inflation FactorsO&M Inflation Rate2.0%Fossil Fuel Inflation Rate5.0%Wood Fuel Inflation Rate3.0%Electricity Inflation Rate5.0%Discount Rate for Net Present Value Calculation 3.0%Year Year Year Year Year Year Year Year Year Year Year Year Year Year Year Year Year YearCash flow Descriptions Unit Costs HeatingSource ProportionAnnual Heating Source VolumesHeating Units 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 20 25 30Existing Heating System Operating CostsDisplaced heating costs $5.65 10000 gal $56,500 $59,325 $62,291 $65,406 $68,676 $72,110 $75,715 $79,501 $83,476 $87,650 $92,033 $96,634 $101,466 $106,539 $111,866 $142,773 $182,218 $232,562Displaced heating costs $5.65 1400 gal $7,910 $8,306 $8,721 $9,157 $9,615 $10,095 $10,600 $11,130 $11,687 $12,271 $12,885 $13,529 $14,205 $14,915 $15,661 $19,988 $25,511 $32,559Displaced heating costs $0.000 gal $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0Displaced heating costs $0.000 gal $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0Biomass System Operating CostsWood Fuel ($/ton, delivered to boiler site)$200.00 85% 99 cords $19,835 $20,430 $21,043 $21,675 $22,325 $22,995 $23,684 $24,395 $25,127 $25,881 $26,657 $27,457 $28,281 $29,129 $30,003 $34,781 $40,321 $46,743Small load existing fuel$5.65 15% 1500 gal $8,475 $8,899 $9,344 $9,811 $10,301 $10,816 $11,357 $11,925 $12,521 $13,148 $13,805 $14,495 $15,220$15,981 $16,780 $21,416 $27,333 $34,884Small load existing fuel$5.65 15% 210 gal $1,187 $1,246 $1,308 $1,374 $1,442 $1,514 $1,590 $1,670 $1,753 $1,841 $1,933 $2,029 $2,131 $2,237 $2,349 $2,998 $3,827 $4,884Small load existing fuel$0.00 15% 0 gal $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0Small load existing fuel$0.00 15% 0 gal $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0Additional Operation and Maintenance Costs$11,200 $11,424 $11,652 $11,886 $12,123 $12,366 $12,613 $12,865 $13,123 $13,385 $13,653 $13,926 $14,204 $14,488 $14,778 $16,316 $18,014 $19,889Additional Operation and Maintenance Costs First 2 years$1,600 $1,632Additional Electrical Cost $0.650$650 $683 $717 $752 $790 $830 $871 $915 $960 $1,008 $1,059 $1,112 $1,167 $1,226 $1,287 $1,643 $2,096 $2,675Annual Operating Cost Savings$21,463$23,317$26,948$29,066$31,309$33,685$36,200$38,862$41,679$44,659$47,811$51,144$54,668$58,393$62,330$85,606$116,137$156,044Financed Project Costs - Principal and Interest0000000000 Displaced System Replacement Costs (year one only)0Net Annual Cash Flow21,463 23,317 26,948 29,066 31,309 33,685 36,200 38,862 41,679 44,659 47,811 51,144 54,668 58,393 62,330 85,606 116,137 156,044Accumulated Cash Flow21,463 44,780 71,728 100,793 132,102 165,787 201,987 240,848 282,527 327,186 374,997 426,141 480,809 539,203 601,533980,472 1,496,810 2,192,971Additional Power UseAdditional MaintenanceSimple Payback: Total Project Cost/Year One Operating Cost Savings:Net Present Value (30 year analysis):Net Present Value (20 year analysis):
Fuel Oil Fuel Oil Wood Fuel Oil Wood Year 1 NPV NPV 20 Yr 30 YrLine Project Usage Unit Cost Fuel Cost & Elec Fuel Additional Operating 30 yr 20 yr B/C B/C ACF ACF ACF YRNo. Cost Gal $/Gal. $/cord ton Inflation Inflation O&M Savings at 3% at 3% Ratio Ratio YR 10 YR 20 YR 30 ACF=PCAll Options - Base CasesB.1 $670,000 10,000 $5.65 $375 5.0% 3.0% $1,600 $5,199 $579,979 $286,108 0.43 0.87 $118,174 $420,716 $1,053,449 25C.1 $298,000 10,000 $5.65 $200 5.0% 3.0% $11,200 $17,176 $1,054,942 $571,617 1.92 3.54 $270,543 $823,607 $1,862,159 11C.2 $325,000 11,400 $5.65 $200 5.0% 3.0% $11,200 $21,463 $1,246,405 $682,006 2.10 3.84 $327,186 $980,472 $2,192,971 101Option C.2 is the strongest economic case and will be used for further sensitivity analysis.23C.2 - Adjusting Fuel Oil Cost4 $325,000 11,400 $3.50 $200 5.0% 3.0% $11,200 $630 $433,291$193,391 0.60 1.33 $65,144 $291,592 $808,817 215 $325,000 11,400 $4.00 $200 5.0% 3.0% $11,200 $5,475 $622,387 $307,023 0.94 1.92 $126,084 $451,797 $1,130,713 176 $325,000 11,400 $4.10 $200 5.0% 3.0% $11,200 $6,444 $660,207 $329,749 1.01 2.03 $138,272 $483,838 $1,195,093 177 $325,000 11,400 $4.50 $200 5.0% 3.0% $11,200 $10,320 $811,484 $420,654 1.29 2.50 $187,024 $612,001 $1,452,610 158 $325,000 11,400 $5.00 $200 5.0% 3.0% $11,200 $15,165 $1,000,580 $534,285 1.64 3.08 $247,964 $772,206 $1,774,506 129 $325,000 11,400 $5.50 $200 5.0% 3.0% $11,200 $20,010 $1,189,676 $647,917 1.99 3.66 $308,904 $932,410 $2,096,402 1110 $325,000 11,400 $6.00 $200 5.0% 3.0% $11,200 $24,855 $1,378,772 $761,548 2.34 4.24 $369,844 $1,092,615 $2,418,298 101112C.2 - Adjusting Fuel Oil Cost and Wood Fuel Cost13 $325,000 11,400 $3.70 $150 5.0% 3.0% $11,200 $7,526 $653,362 $335,132 1.03 2.01 $146,368 $488,920 $1,173,495 1714 $325,000 11,400 $4.00 $150 5.0% 3.0% $11,200 $10,433 $766,820 $403,311 1.24 2.36 $182,932 $585,043 $1,366,633 1515 $325,000 11,400 $4.50 $150 5.0% 3.0% $11,200 $15,278 $955,916 $516,942 1.59 2.94 $243,872 $745,247 $1,688,529 1316 $325,000 11,400 $5.00 $150 5.0% 3.0% $11,200 $20,123 $1,145,012 $630,574 1.94 3.52 $304,812 $905,452 $2,010,425 1117 $325,000 11,400 $4.00 $200 5.0% 3.0% $11,200 $5,475 $622,387 $307,023 0.94 1.92 $126,084 $451,797 $1,130,713 1718 $325,000 11,400 $4.10 $200 5.0% 3.0% $11,200 $6,444 $660,207 $329,749 1.01 2.03 $138,272 $483,838 $1,195,093 1719 $325,000 11,400 $4.50 $200 5.0% 3.0% $11,200 $10,320 $811,484 $420,654 1.29 2.50 $187,024 $612,001 $1,452,610 1520 $325,000 11,400 $5.00 $200 5.0% 3.0% $11,200 $15,165 $1,000,580 $534,285 1.64 3.08 $247,964 $772,206 $1,774,506 122122 NPV: Net Present ValueYR ACF=PC : Year Accumulated Cash Flow equals Project CostJuly 24, 2012Economic Sensitiviy AnalysisMinto Biomass Heating System
APPENDIX C
Site Plan
LAKEVIEW LODGEMINTO HEALTHCLINICCOMMUNITY CENTERFUTURE FIRE HALL1000'500'250'0SCALE: 1:500MISSOULA, MT(406)728-9522Fax (406)728-8287Date®BIOMASS PRE-FEASIBILITY ASSESSMENTMINTO, ALASKAMINTO OVERVIEWSSFNHR07/24/2012FEDCJ:mintoSITE PLANNORTHREF.LEGENDPIPE ROUTINGBOILER ROOM
BOILER PLANT62'-6"25'-0"100'50'25'0SCALE: 1:50NORTHREF.LEGENDPIPE ROUTINGBOILER ROOMMISSOULA, MT(406)728-9522Fax (406)728-8287Date®BIOMASS PRE-FEASIBILITY ASSESSMENTMINTO, ALASKALAKEVIEW LODGE & MINTO HEALTH CLINICSSFNHR07/24/2012FEDCJ:mintoLAKEVIEW LODGEMINTO HEALTHCLINICSITE PLAN
APPENDIX D
Air Quality Report
55 Railroad Row White River Junction, Vermont 05001
TEL 802.295.4999 FAX 802.295.1006 www.rsginc.com
INTRODUCTION
At your request, RSG has conducted an air quality feasibility study for three biomass energy
installations in Manley, Minto and Nenana. These sites are located in the interior of Alaska near
Fairbanks. The following equipment is proposed:
Minto ‐ one 300,000 Btu/hr (heat output) cord wood boiler at the Minto Health Clinic.
Manley ‐ one 150,000 Btu/hr (heat output) cord wood boiler at the Village Express
Maintenance Shop.
Nenana – one 4,200,000 Btu/hr (heat output) wood chip boiler at the Nenana School.
MINTO STUDY AREA
A USGS map of the Minto study area is provided in Figure 1 below. As shown, the area is flat
with much low‐lying areas to the east and hilly to the west. The site is adjacent to a hillside. The
area is relatively sparsely populated. Our review of the area did not reveal any significant
emission sources or ambient air quality issues.
To: Nick Salmon
From: John Hinckley
Subject: Fairbanks Cluster Feasibility Study
Date: 24 July 2012
Fairbanks Air Quality Feasibility Study Resource Systems Group, Inc.
24 July 2012 page 2
Figure 1: USGS Map Illustrating the Minto Study Area
Fairbanks Air Quality Feasibility Study Resource Systems Group, Inc.
24 July 2012 page 3
Figure 2 shows CTA Architects’ plan of the location of the proposed biomass facility and the
surrounding buildings in Minto. The site is relatively flat and sparsely populated with buildings.
The facility will be located in a remote building on the southeast side of two buildings. The
precise dimensions of that building, the stack location and dimensions, and the biomass
equipment specifications have not been determined. The degree of separation of the biomass
building from the other buildings will create a buffer for emissions dispersion.
Figure 2: Location of Proposed Facility in Minto
Fairbanks Air Quality Feasibility Study Resource Systems Group, Inc.
24 July 2012 page 4
A USGS map of the Manley study area is provided Figure 3. As shown, the area is hilly to
mountainous to the north and flat to the south. The site is near the higher terrain to the north.
The area is relatively sparsely populated. Our review of the area did not reveal any significant
emission sources or ambient air quality issues.
Figure 3: USGS Map Illustrating the Manley Hot Springs Study Area
Fairbanks Air Quality Feasibility Study Resource Systems Group, Inc.
24 July 2012 page 5
Figure 4 shows CTA Architects’ plan of the location of the proposed biomass facility and the
surrounding buildings. The site is surrounded by forest, relatively flat and has only a few
buildings. The facility will be located in a new building on the west side of the site. A generator
building is also indicated on the plan. The precise dimensions of that building, the stack location
and dimensions, and the biomass equipment specifications have not been determined.
Figure 4: Location of Proposed Facility in Manley
Fairbanks Air Quality Feasibility Study Resource Systems Group, Inc.
24 July 2012 page 6
A USGS map of the Nenana study area is provided Figure 3. As shown, the area is hilly to
mountainous to the north and flat to the south and northeast. The site is across the river from
higher terrain to the north. The area is moderately populated relative to the other sites
discussed. Our review of the area did not reveal any significant emission sources or ambient air
quality issues.
Figure 5: USGS Map Illustrating the Nenana Study Area
Fairbanks Air Quality Feasibility Study Resource Systems Group, Inc.
24 July 2012 page 7
Figure 6 shows CTA Architects’ plan of the location of the proposed biomass facility at the
Nenana School and the surrounding buildings. The site is relatively flat and relatively densely
populated with one to two story tall buildings. The proposed biomass equipment will be
installed in a remote building located to the east of the school. This will provide a buffer for
dispersion of air emissions between the stack and surrounding buildings. The precise stack
location and dimensions, and the biomass equipment specifications have not been determined.
Figure 6: Overview of Nenana School Cluster Site
Fairbanks Air Quality Feasibility Study Resource Systems Group, Inc.
24 July 2012 page 8
METEOROLOGY
Meteorological data from Fairbanks, AK was reviewed to develop an understanding of weather
conditions. While Fairbanks is approximately 90 miles, 50 miles, and 45 miles away from
Manley, Minto, and Nenana respectively, it is located in a similar climactic zone (Alaska
Interior) and is therefore a good proxy of weather in those locations. As shown, there is a
relatively high percentage of “calms” or times when the wind is not blowing during the colder
months.1 These conditions create thermal inversions which are unfavorable for the dispersion
of emissions.
Figure 7: Wind Speed Data from Fairbanks, AK
DESIGN & OPERATION RECOMMENDATIONS
The following are suggested for designing the stack:
1 See: http://climate.gi.alaska.edu/Climate/Wind/Speed/Fairbanks/FAI.html
Fairbanks Air Quality Feasibility Study Resource Systems Group, Inc.
24 July 2012 page 9
Burn natural wood, whose characteristics (moisture content, bark content, species,
geometry) results in optimal combustion in the equipment selected for the project.
Do not install a rain cap above the stack. Rain caps obstruct vertical airflow and reduce
dispersion of emissions.
Construct the stack to at least 1.5 times the height of the tallest roofline of the adjacent
building. Hence, a 20 foot roofline would result in a minimum 30 foot stack.
Operate and maintain the boiler according to manufacturer’s recommendations.
Perform a tune‐up at least every other year as per manufacturer’s recommendations
and EPA guidance (see below for more discussion of EPA requirements)
Conduct regular observations of stack emissions. If emissions are not characteristic of
good boiler operation, make corrective actions.
For the Nenana School: while there are no state or federal requirements mandating
advanced emission control from and ESP or baghouse, we feel advanced emission
control should be strongly considered. Alternatively, the school should consider using
pellets in lieu of wood chips.
STATE AND FEDERAL PERMIT REQUIREMENTS
This project will not require an air pollution control permit from the Alaska Department of
Environmental Quality given the boilers’ relatively small size and corresponding quantity of
emissions. However, this project will be subject to new proposed requirements in the federal
“Area Source Rule” (40 CFR 63 JJJJJJ). A federal permit is not needed. However, there are various
record keeping, reporting and operation and maintenance requirements which must be
performed to demonstrate compliance with the requirements in the Area Source Rule. The
proposed changes have not been finalized. Until that time, the following requirements are
applicable:
Submit initial notification form to EPA within 120 days of startup.
Complete biennial tune ups per EPA method.
Submit tune‐up forms to EPA.
Please note the following:
Oil and coal fired boilers are also subject to this rule.
Gas fired boilers are not subject to this rule.
More requirements are applicable to boilers equal to or greater than 10 MMBtu/hr heat
input. These requirements typically warrant advanced emission controls, such as a
baghouse or an electrostatic precipitator (ESP).
The compliance guidance documents and compliance forms can be obtained on the following
EPA web page: http://www.epa.gov/boilercompliance/
Fairbanks Air Quality Feasibility Study Resource Systems Group, Inc.
24 July 2012 page 10
SUMMARY
RSG has completed an air quality feasibility study for Minto, Manley, and Nenana, Alaska. The
boilers are not subject to state permitting requirements, but are subject to federal
requirements. Design criteria have been suggested to minimize emissions and maximize
dispersion.
The following conditions suggest advanced emission control devices (ESP, baghouse) are not
mandatory:
1. The wood boilers, with the exception of the boiler at Nenana, will be relatively small
emission sources.
2. The wood boilers will be located in a separate building which will create a dispersion
buffer between the boiler stack and the building.
3. There are no applicable federal or state emission limits.
Sustained poor meteorology suggests emissions should be minimized as much as possible.
Given these findings, we would recommend at minimum the following be done to minimize
emissions:
1. Nenana: consider burning pellets in lieu of wood chips or consider advanced emission
control. If wood chips are preferable, consider conducting air dispersion modeling to
determine the stack height and degree of emission control.
2. While not mandatory, we recommend exploring the possibility of a cyclone or multi‐
cyclone technology for control of fly ash and larger particulate emissions for all the
aforementioned boilers.
3. Obtain a not‐to‐exceed emission guarantees from boiler equipment vendors.
We also recommend developing a compliance plan for the aforementioned federal
requirements.
Please contact me if you have any comments or questions.
APPENDIX E
Wood Fired Heating Technologies
WOOD FIRED HEATING TECHNOLOGIES
CTA has developed wood-fired heating system projects using cord wood, wood pellet
and wood chips as the primary feedstock. A summary of each system type with the
benefits and disadvantages is noted below.
Cord Wood
Cord wood systems are hand-stoked wood boilers with a limited heat output of 150,000-
200,000 British Thermal Units per hour (Btu/hour). Cord wood systems are typically
linked to a thermal storage tank in order to optimize the efficiency of the system and
reduce the frequency of stoking. Cord wood boiler systems are also typically linked to
existing heat distribution systems via a heat exchanger. Product data from Garn, HS
Tarm and KOB identify outputs of 150,000-196,000 Btu/hr based upon burning eastern
hardwoods and stoking the boiler on an hourly basis. The cost and practicality of stoking
a wood boiler on an hourly basis has led most operators of cord wood systems to
integrate an adjacent thermal storage tank, acting similar to a battery, storing heat for
later use. The thermal storage tank allows the wood boiler to be stoked to a high fire
mode 3 times per day while storing heat for distribution between stoking. Cord wood
boilers require each piece of wood to be hand fed into the firebox, hand raking of the
grates and hand removal of ash. Ash is typically cooled in a barrel before being stock
piled and later broadcast as fertilizer.
Cordwood boilers are manufactured by a number of European manufacturers and an
American manufacturer with low emissions. These manufacturers currently do not
fabricate equipment with ASME (American Society of Mechanical Engineers)
certifications. When these non ASME boilers are installed in the United States,
atmospheric boilers rather than pressurized boilers are utilized. Atmospheric boilers
require more frequent maintenance of the boiler chemicals.
Emissions from cord wood systems are typically as follows:
PM2.5 >0.08 lb/MMbtu
NOx 0.23 lb/MMbtu
SO2 0.025 lb/MMbtu
CO2 195 lb/MMbtu
Benefits:
Small size
Lower cost
Local wood resource
Simple to operate
Disadvantages:
Hand fed - a large labor commitment
Typically atmospheric boilers (not ASME rated)
Thermal Storage is required
Page 1
Wood Pellet
Wood pellet systems can be hand fed from 40 pound bags, hand shoveled from 2,500
pound sacks of wood pellets, or automatically fed from an adjacent agricultural silo with
a capacity of 30-40 tons. Pellet boilers systems are typically linked to existing heat
distribution systems via a heat exchanger. Product data from KOB, Forest Energy and
Solagen identify outputs of 200,000-5,000,000 Btu/hr based upon burning pellets made
from waste products from the western timber industry. A number of pellet fuel
manufacturers produce all tree pellets utilizing bark and needles. All tree pellets have
significantly higher ash content, resulting in more frequent ash removal. Wood pellet
boilers typically require hand raking of the grates and hand removal of ash 2-3 times a
week. Automatic ash removal can be integrated into pellet boiler systems. Ash is
typically cooled in a barrel before being stock piled and later broadcast as fertilizer.
Pellet storage is very economical. Agricultural bin storage exterior to the building is
inexpensive and quick to install. Material conveyance is also borrowed from agricultural
technology. Flexible conveyors allow the storage to be located 20 feet or more from the
boiler with a single auger.
Emissions from wood pellet systems are typically as follows:
PM2.5 >0.09 lb/MMbtu
NOx 0.22 lb/MMbtu
SO2 0.025 lb/MMbtu
CO2 220 lb/MMbtu
Benefits:
Smaller size (relative to a chip system)
Consistent fuel and easy economical storage of fuel
Automated
Disadvantages:
Higher system cost
Higher cost wood fuel ($/MMBtu)
Page 2
Page 3
Wood Chip
Chip systems utilize wood fuel that is either chipped or ground into a consistent size of
2-4 inches long and 1-2 inches wide. Chipped and ground material includes fine
sawdust and other debris. The quality of the fuel varies based upon how the wood is
processed between the forest and the facility. Trees which are harvested in a manner
that minimizes contact with the ground and run through a chipper or grinder directly into
a clean chip van are less likely to be contaminated with rocks, dirt and other debris. The
quality of the wood fuel will also be impacted by the types of screens placed on the
chipper or grinder. Fuel can be screened to reduce the quantity of fines which typically
become airborne during combustion and represent lost heat and increased particulate
emissions.
Chipped fuel is fed from the chip van into a metering bin, or loaded into a bunker with a
capacity of 60 tons or more. Wood chip boilers systems are typically linked to existing
heat distribution systems via a heat exchanger. Product data from Hurst, Messersmith
and Biomass Combustion Systems identify outputs of 1,000,000 - 50,000,000 Btu/hr
based upon burning western wood fuels. Wood chip boilers typically require hand raking
of the grates and hand removal of ash daily. Automatic ash removal can be integrated
into wood chip boiler systems. Ash is typically cooled in a barrel before being stock piled
and later broadcast as fertilizer.
Emissions from wood chip systems are typically as follows:
PM2.5 0.21 lb/MMbtu
NOx 0.22 lb/MMbtu
SO2 0.025 lb/MMbtu
CO2 195 lb/MMbtu
Benefits:
Lowest fuel cost of three options ($/MMBtu)
Automated
Can use local wood resources
Disadvantages:
Highest initial cost of three types
Larger fuel storage required
Less consistent fuel can cause operational and performance issues