HomeMy WebLinkAboutRampart Village Wood Fired Heating System FinalReport WES Energy 07-28-2015-WOODHigh Efficiency Low Emission
Wood Fired Heating System
Pre-Feasibility Report
July 28, 2015
Version: Final
WES Energy & Environment, LLC
902 Market Street • Meadville, PA 16335
(814) 337‐8223
Prepared for:
Rampart Village Council
In Partnership with :
Fairbanks Economic Development CorporaƟon
Alaska Wood Energy Development Task Group
Prepared By:
Biomass Prefeasibility Report Date: July 28, 2015 Rampart Village Council
Final
WES Energy & Environment
Table of Contents
1.0 Executive Summary .............................................................................................................. 1
2.0 Existing Fuel Usage & Heating Systems ............................................................................... 2
2.1 RVC Offices in the Multipurpose Building ........................................................................ 2
2.2 Laundromat ...................................................................................................................... 6
3.0 Forest Resource and Fuel Availability ................................................................................ 13
4.0 Proposed Biomass Systems................................................................................................ 14
4.1 Multipurpose Building .................................................................................................... 14
4.2 Laundromat .................................................................................................................... 16
4.3 District System Serving the Multipurpose Building and the Laundromat ..................... 18
5.0 Benefit/Cost Analysis ......................................................................................................... 20
6.0 Conclusions & Recommendations ..................................................................................... 23
7.0 General Biomass Technology Information ........................................................................ 24
Appendix A – Conceptual Drawings
Appendix B – Capital Cost Estimates
Appendix C – 20 Year Financing at 4% APR Cash Flow Analysis
Appendix D – Sensitivity Analysis of Annual Savings to Oil and Biomass Prices
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1.0 EXECUTIVE SUMMARY
This preliminary feasibility study evaluates options for Rampart Village Council (RVC) to utilize
high efficiency low emission wood fired technologies at the Multipurpose Building and
Laundromat. Installation of a wood fired heating system would present RVC with the
opportunity to reduce operating costs and utilize a renewable fuel for heating. The
Multipurpose Building was previously used as a school and will be repurposed to accommodate
offices for RVC employees and potentially sublet a portion to reopen a school. An aerial map of
Rampart is provided in Appendix A that identifies the buildings evaluated in this study.
The multipurpose building was the school for the community from 1986 to 1999. The building
was closed in 1999 and has been unused since. RVC received a grant to renovate and
repurpose the building, which will begin in 2015. Hot water boilers firing on #1 fuel oil were
used for space heating and domestic hot water when the building was in operation. The
boilers are planned to be retrofitted with new burners and reused. Historic fuel use is
unavailable.
The laundromat was constructed in 1998 and provides community access to showers,
restrooms, and coin operated washers & dryers. Historic fuel oil use was provided by RVC. #1
fuel oil is used for space heating, domestic hot water heating, and for clothes dryers equipped
with hot water coils.
Both buildings utilize #1 fuel oil fired boiler plants for space heating and domestic hot water
heating. Three options are evaluated using factory containerized gasification style indoor cord
wood boilers. Option 1 considers heating the RVC offices that are planned to be constructed in
the unused Multipurpose Building, Option 2 considers heating the laundromat, and Option 3
considers heating both buildings using a district system. A summary of the costs and benefits
for each option are listed in Table ES1.
Table ES1 – Cost and Benefit Summary
Option Estimated
Capital Cost
1st Year Net Annual
Operating Savings
Simple
Payback,
Years
20 Year Net
Present Value
20 Year
B/C Ratio
1 : RVC Offices $135,556 $4,343 31.2 $ (50,621) 0.63
2 : Laundromat $158,700 $4,992 31.8 $ (61,031) 0.62
3 : District System $324,013 $8,495 38.1 $ (157,704) 0.51
Notes:
1 – Net Annual Operating Savings include costs for wood fuel, supplemental fossil fuel, and operation &
maintenance (O&M) costs.
2 – 20 Year Net Present Value takes the present value of the operating savings for each year using a nominal
discount rate of 3.1% as published in the “Energy Price Indices and Discount Factors for Life‐Cycle Cost Analysis ‐
2014” and the initial capital outlay of the total project cost. A value greater than zero means that savings are
greater than expenses over 20 years in the value of today’s dollars.
3 – 20 Year Benefit/Cost (B/C) Ratio is calculated by dividing the present value of net annual operating savings over
a 20 year period with a discount rate of 3.1% by the Estimated Capital Cost. A value greater than 1 means the
benefits exceed the costs over a 20 year period.
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2.0 EXISTING FUEL USAGE & HEATING SYSTEMS
Rampart is a high fuel cost community with prices for #1 fuel currently at $6.50 per gallon.
Access to Rampart is limited to bush planes and boats. #1 fuel oil is flown in by plane,
transferred to a portable storage tank, and towed from the air strip using a D8 bulldozer to fill
above ground tanks in the community. Historic fuel use was provided for the Laundromat,
however, fuel use for the Multipurpose Building is unavailable.
2.1 RVC OFFICES IN THE MULTIPURPOSE BUILDING
The Multipurpose Building is currently unoccupied and unheated. The building is planned for
renovation in 2015 which will repurpose a portion of the building to accommodate RVC offices.
The new offices are anticipated to be 2,600 ft2. The remaining portion of the building is under
consideration by Yukon Flats School District to set up a classroom, which would be sublet from
RVC. A separate heating system will be used for the remainder of the building. Figures 2.1‐1
and 2.1‐2 show the exterior of the Multipurpose Building.
Figure 2.1‐1 – Multipurpose Building Exterior
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Figure 2.1‐2 – Multipurpose Building Exterior
Two Burnham hot water boilers are decommissioned in the mechanical room of the
Multipurpose Building. They have been inspected by the State Boiler Inspector and were
deemed safe to reuse with new oil burners. Figure 2.1‐3 shows a picture of the currently
decommissioned boilers that will receive new oil burners with the renovation.
Figure 2.1‐3 – Multipurpose Building Boilers
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The renovation will abandon in place the existing hot water heating distribution system and
install new piping and pumps from the boilers to baseboard heaters that will be installed in new
offices. Glycol is used in the system since outdoor temperatures can reach ‐70ᵒF. Drain pans
underneath the boilers were full of glycol on the site visit. When the system was operational,
fuel oil was pumped from the bulk storage tank into a day tank located in the boiler room. The
Interior Regional Housing Authority (IRHA) is currently designing the renovation and new
heating system, however this has not yet been completed.
The annual energy use for space heating in the RVC offices has been estimated based on the
floor space anticipated for use, the annual heating degree days (HDD) using a base temperature
of 65ᵒF, and the Thermal Energy Use Intensity per HDD value of 7.4 Btus/Ft2/HDD1. Table 2.1‐1
shows the estimated annual energy use that would be used for space heating based on the
anticipated floor space used for the RVC Offices.
Table 2.1‐1 – Estimated Annual Energy Use for Heating the RVC Multipurpose Building Offices
Building
RVC Office
Floor
Space, Ft2
April 2014 ‐
March 2015
Annual HDD,
65F
Thermal
EUI/HDD
Annual Boiler
Input Energy
Use for Space
Heating,
mmBtu
Estimated
Boiler
Efficiency
Estimated
Annual Space
Heating Energy
Use, mmBtu
RVC Offices in
MP Building 2,600 14,205 7.4 273.3 80% 219
Notes:
1‐ Annual heating energy use considers only the floor space that is anticipated to be used for RVC offices as
requested by RVC. Remaining floor space will be heated using a waste oil heater or a separate system by
future tenants.
2‐ Thermal EUI/HDD value of 7.4 is used to estimate annual heating energy use in the building. This value is
based on the Alaska Housing Finance Corporation report titled “Energy Efficiency of Public Buildings in
Alaska : Metrics and Analysis”.
The estimated annual heating demand from Table 2.1‐1 is then distributed across the year
based on local weather data to develop a daily average heating demand curve. Figure 2.1‐4
shows how the daily average heating demand for the RVC Offices would be expected to vary
over the course of a year for space heating only. During a 24‐hr period, the actual load will vary
above and below this average value.
1 Wiltse, N., Madden, D., Valentine, B. (2014). Energy Efficiency of Public Buildings in Alaska: Metrics and Analysis.
Fairbanks, AK: Cold Climate Housing Research Center.
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Figure 2.1‐4 – RVC Offices Estimated Daily Average Space Heating Demand (4/2014 – 3/2015)
Note: The daily average heating demand model is based on local weather data and annual fuel usage provided by
RVC. Actual demand would fluctuate above and below the average heating demand values shown over a 24‐hr
period.
A load duration curve was developed using the daily average heating demand curves. Load
duration curves sort the daily average heating demand over the course of a year from highest
to lowest and plot it over the number of days to show the annual range of facility heating
demand. Figure 2.1‐5 shows the estimated load duration curve for the RVC Offices in the
Multipurpose Building.
0
10,000
20,000
30,000
40,000
50,000
60,000
70,000
Heating Demand, Btu/hrDaily Average Demand
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Figure 2.1‐5 – RVC Offices Space Heating Load Duration Curve (4/2014 – 3/2015)
Note: The load duration curve is based on local weather data and annual fuel usage provided by RVC. Actual
demand would fluctuate above and below the average heating demand values shown over a 24‐hr period.
2.2 LAUNDROMAT
A 2,140 ft2 Laundromat was constructed in 1998 that contains washers, dryers, showers, and
bathrooms for the community. The facility used approximately 2,450 gallons of #1 fuel oil
annually for space heating, domestic hot water heating, and laundry services. Annual
expenditures are approximately $15,925 at the current fuel price of $6.50 per gallon. An above
ground 500 gallon fuel oil tank is used for onsite storage. Figure 2.2‐1 shows the exterior of the
Laundromat.
0
10,000
20,000
30,000
40,000
50,000
60,000
70,000
11223344556677889100111122133144155166177188199210221232243254265276287298309320331342353364Heating Demand, Btu/hrDays
Daily Average Demand
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Figure 2.2‐1 – Laundromat Building Exterior
The boiler room contains two Weil McLain model 678 hot water boilers rated at 643,000 Btu/hr
each while firing on #1 fuel oil. One boiler can meet the heating demands of the building with
the second boiler remaining for backup. The Laundromat boilers are shown in Figure 2.2‐2.
Figure 2.2‐2 – Laundromat Boilers
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The heating distribution system uses a glycol/water mixture with a primary pumping system.
There are 3 zones with pumps circulating water to a space heating zone, a dryer heating zone,
and a domestic hot water heating zone. Baseboard fin tube heaters and unit heaters provide
space heating for rooms. Thermostats in each room and control valves on the fin tube heaters
are the only control for the system. Domestic hot water is heated indirectly using the heating
boilers and stored in a 190 gallon Ajax Boiler, Inc DHW storage tank. There is no room in the
existing boiler room to locate a wood fired boiler system or thermal storage tanks.
Two Huebsch Originators 25 pound front load commercial washers, two Speed Queen top load
washers, and four Hoyt‐Windsor II dryers with heating capacities of 95,000 Btu/hr each are
provided for laundry services. The dryers are equipped with a hydronic package that uses hot
water from the heating boilers as the heat source for drying. Figures 2.2‐3 and 2.2‐4 show the
laundry equipment.
Figure 2.2‐3 – RVC Laundromat Washing Machines
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Figure 2.2‐4 – RVC Laundromat Dryers
The laundry equipment is coin operated and coin collection records were provided by RVC for
1/1/2015 through 5/27/2015. The washers and dryers use tokens that are purchased for $0.50
apiece. Four washing machines are utilized in the laundromat with two large commercial front
load washers and two top load washers. The washers require 12 tokens for front load washers
and 6 tokens for top load washers per 23.5 minute cycle. The dryers require 1 token for 7
minutes of drying time. Table 2.2‐1 shows the token collection records and estimated energy
use for the laundry equipment. All energy use values are shown as energy used by the
equipment and would correspond to boiler output energy.
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Table 2.2‐1 – 5 Month Laundry Token Collection Records and Estimated Energy Use
Usage Period
Washer
Tokens
Collected
Dryer
Tokens
Collected
Estimated
Washer
Energy Use,
mmBtu
Estimated
Dryer Energy
Use, mmBtu
Total Estimated
Laundry Energy
Use, mmBtu
Extrapolated
Annual Laundry
Use, mmBtu
1/1‐1/15/15 46 34 0.02 0.40 0.42
‐
1/16‐1/28/15 12 14 0.01 0.16 0.17
1/29‐2/11/15 28 29 0.01 0.34 0.35
2/12‐2/16/15 14 14 0.01 0.16 0.17
2/17‐3/3/15 36 32 0.02 0.37 0.39
3/4/‐3/16/15 35 42 0.02 0.49 0.51
3/17‐3/29/15 38 43 0.02 0.50 0.52
3/30‐4/9/15 26 30 0.01 0.35 0.36
3/31‐4/14/15 18 15 0.01 0.18 0.18
4/15‐4/23/15 29 14 0.01 0.16 0.18
4/24‐5/1/15 28 21 0.01 0.25 0.16
5/2/‐5/8/15 35 19 0.02 0.22 0.25
5/9‐5/14/15 21 26 0.01 0.30 0.30
5/15‐5/27/15 32 38 0.02 0.44 0.44
398 371 0.21 4.33 4.53 10.88
Laundry energy use is estimated using the assumptions provided in Table 2.2‐2.
Table 2.2‐2 – Laundry Energy Use Assumptions
Item Value and Unit Source
Front load washer use vs. top load washer 50% RVC
Front load washer water use per cycle 35 gallons WES E&E assumption
Top load washer water use per cycle 25 gallons
http://www.speedqueencommercial.com/vend/en‐
us/news/newsletter/2014‐april‐cost‐per‐cycle‐‐‐
front‐load‐washer‐and‐top‐load‐washer‐.aspx
Percentage of Hot Water per Washer Cycle 25%
Water Management, Inc., et al. 2006. Report on
the Monitoring and Assessment of Water Savings
from the Coin‐Operated Multi‐Load Clothes
Washer Voucher Initiative Program. Prepared for
the San Diego Water Authority
Density of Water at 50ᵒF 8.343 lbs/gallon WES E&E assumption
Laundry hot water temperature rise 70ᵒF WES E&E assumption
Density of Water at 120ᵒF 8.25 lbs/gallon WES E&E assumption
Dryer Heating Demand 95,000 Btu/hr Hoyt‐Windsor
Front load washer token use per cycle 12 Tokens RVC
Top load washer token use per cycle 6 Tokens RVC
Dryer time per token 7 minutes RVC
Cool down period of dryer cycle 0 Minutes WES E&E assumption
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Annual hot water use for showers and the associated energy use is estimated for the
laundromat. Assumptions used to estimate annual energy use include a shower length of 8
minutes, 10 gallons of hot water use per shower, a hot water temperature rise of 70ᵒF, and 20
showers per day. Table 2.2‐3 shows the estimated annual shower hot water energy use.
Table 2.2‐3 – Estimated Annual Shower Hot Water Energy Use
Estimated
Shower Length,
Minutes
Hot Water
Use, Gallons
Estimated
Energy Use per
Shower, Btu
Estimated Energy
Use per Year,
Output mmBtu
8 10 5,775 42.2
Note: Average shower length and hot water use are based on the values provided by the DOE
website http://energy.gov/eere/femp/energy‐cost‐calculator‐electric‐and‐gas‐water‐heaters‐0
Fuel deliveries for April 2014 through March 2015 were provided by RVC. Table 2.2‐4 shows
the annual fuel oil delivered to the Laundromat, estimated boiler efficiency, estimated total
annual heating energy use, and the energy breakdown for laundry, showers, and space heating.
Table 2.2‐4 – Laundromat Estimated Annual Energy Use Summary
April 2014 ‐
March 2015
#1 Oil Use,
Gallons
Annual
Boiler Input
Energy,
mmBtu
Estimated
Boiler
Efficiency
Total Annual
Boiler Output
Energy,
mmBtu
Estimated
Annual Laundry
Energy Use,
mmBtu
Estimated
Annual Shower
Energy Use,
mmBtu
Estimated
Annual Space
Heating Energy
Use, mmBtu
2,450 328 80% 263 11.2 42.2 209
Note: Annual space heating energy is estimated by subtracting the Annual Laundry and Shower Energy Use from
the Total Boiler Output Energy.
The Estimated Annual Space Heating Energy Use is used for the purposes of load modeling and
boiler sizing in this memorandum. Figure 2.2‐5 shows how the daily average heating demand
for the Laundromat would be expected to vary over the course of a year for space heating only.
During a 24‐hr period, the actual load will vary above and below this average value. Potential
peak loads are estimated to be much higher than the average load due to the potential to
operate four dryers at the same time, however the duration is short and actual use of laundry
equipment has been minimal compared to the heating demand of the building.
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Figure 2.2‐5 – Laundromat Estimated Daily Average Space Heating Demand (4/2014 – 3/2015)
Note: The daily average heating demand model is based on local weather data and annual fuel usage provided by
RVC. Actual demand would fluctuate above and below the average heating demand values shown over a 24‐hr
period. Heating demands for the washers, dryers, and showers are not included in the curve since equipment use is
minimal compared to the space heating demand.
A load duration curve was developed using the daily average heating demand curves. Load
duration curves sort the daily average heating demand over the course of a year from highest
to lowest and plot it over the number of days to show the annual range of facility heating
demand. Figure 2.2‐6 shows the estimated load duration curve for the Laundromat’s space
heating demand.
0
10,000
20,000
30,000
40,000
50,000
60,000
70,000
Heating Demand, Btu/hrDaily Average Demand
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Figure 2.2‐6 – Laundromat Space Heating Load Duration Curve (4/2014 – 3/2015)
Note: The load duration curve is based on local weather data and annual fuel usage provided by RVC. Actual
demand would fluctuate above and below the average heating demand values shown over a 24‐hr period. Heating
demands for the washers, dryers, and showers are not included in the curve since equipment use is minimal
compared to the space heating demand.
3.0 FOREST RESOURCE AND FUEL AVAILABILITY
The area surrounding Rampart is heavily forested. RVC plans to set up harvesting plans with
private residents, Native Corporations, and the Alaska DOT to sustainably harvest wood for fuel.
Landowners were contacted and no existing Forest Stewardship Plans are in place.
A management plan could incorporate setting up a fire break to help protect the village from
fire hazards. Additionally, large quantities of drift wood are available after the ice breakup on
the Yukon River. This driftwood could be harvested and air dried over the course of a season to
be used as fuel. RVC anticipates that cord wood can be purchased from local harvesters for
$300 per cord. Table 3.0‐1 summarizes the available fuels for heating as well as their cost per 1
million Btu’s (mmBtu) of boiler output comparison.
0
10,000
20,000
30,000
40,000
50,000
60,000
70,000
11223344556677889100111122133144155166177188199210221232243254265276287298309320331342353364Heating Demand, Btu/hrDays
Daily Average Demand
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Table 3.0‐1 – Fuel Pricing and Cost of Energy for Heating
Fuel, Unit Boiler Type Cost per
Unit
Input Heating
Value, mmBtu
per Unit
Estimated
Boiler
Efficiency
Appliance
Output
Heating Value,
mmBtu/Unit
Appliance
Output
Heating Cost,
$/mmBtu
Seasoned Cord
Wood, Cord
Indoor Gasification
Boiler $300.00 17.0 70.0% 11.9 $25.21
#1 Fuel Oil,
Gallon
Vented Space
Heater $6.50 0.134 80.0% 0.107 $60.63
Note: Assumes 20% moisture content wet basis for cord wood and assumes that wood use is made up of 50% black
spruce at 15.9 mmBtu/cord and 50% white spruce at 18.1 mmBtu/cord.
4.0 PROPOSED BIOMASS SYSTEMS
High efficiency low emission cord wood boilers are evaluated for use in the Laundromat and the
RVC offices planned for construction in the Multipurpose Building. The economics are
considered for using dedicated systems serving each building as well as a district system that
interconnects the heating systems for both buildings. Space within each building is limited for
locating a new wood fired boiler, therefor containerized systems are considered for each
option.
4.1 MULTIPURPOSE BUILDING
An advanced combustion unit and hot water boiler capable of firing on seasoned cord wood
sized at approximately 100,000 Btu/hr of heat output is evaluated. The boiler would be
combined with approximately 800 gallons of thermal storage to efficiently meet the RVC office
space range of heating needs. This boiler size was chosen because typically it is the smallest
boiler offered by manufacturers. The boiler operator would have to take care to charge the
firebox based on expected load to ensure that the boiler does not idle and produce excess
smoke.
Due to space constraints in the building, the system will be located in a containerized system
adjacent to the Multipurpose Building. The containerized system will include the cord wood
boiler, hot water thermal storage system, and circulation pumps. The system will interconnect
with the hydronic system using distribution piping in a utilidor. Propylene glycol should be used
as the heating fluid due to extreme cold temperatures experience throughout the winter.
Additionally, heat trace wiring should be installed in the utilidor as a safety precaution.
The hot water thermal storage will hold approximately 180,000 Btu assuming a 60% propylene
glycol concentration, 190ᵒF storage temperature, and 160ᵒF distribution return temperature.
This would provide 1 hours and 50 minutes of load to charge the tank from 160ᵒF to 190ᵒF. The
boiler will be over sized but is typically the smallest size available for an ASME rated cord wood
boiler. The large volume of thermal storage will mitigate the effects of an oversized boiler. The
estimated coverage using the cord wood boiler for the RVC Offices planned for construction in
the Multipurpose Building is shown in Figure 4.2‐1.
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Figure 4.1‐1 – Estimated Cord Wood System Coverage of Load Duration Curve
Note: The load duration curve model is based on local weather data and annual fuel delivery volumes provided by
RVC. Potential coverage of 40% is shown while estimating a minimum turndown of 40%. Actual coverage will
depend on management of loads and the use of thermal storage.
Figure 4.1‐1 shows 40% coverage of the space heating load duration curve using the cord wood
system. The existing fuel oil system in the boiler room will supplement the cord wood system
as needed. Actual coverage will vary depending on weather conditions, peak demands,
equipment operation schedules, and periods when the boilers are shut down for maintenance.
The 100,000 Btu/hr system is large for the building heating demand, but is typically the smallest
size offered by manufacturers. The coverage assumes a minimum boiler turndown of 40% with
the cord wood system. Cord wood boilers can turndown more than 40%, however efficiency
drops off quickly below this point. The 800 gallon thermal storage system will provide a large
buffer on the system and reduce periods operating below 40% boiler output. This report
assumes 70% coverage for the cord wood system for estimating the potential fuel use and
savings for the Multipurpose Building.
Cord wood used in the system should be stacked and seasoned (air dried) for at least a year to
reduce to moisture content in the wood. A 500 ft2 covered pole style building with walls that
allow air to flow through is recommended to store the 13 cords of wood that would be required
0
10,000
20,000
30,000
40,000
50,000
60,000
70,000
11223344556677889100111122133144155166177188199210221232243254265276287298309320331342353364Heating Demand, Btu/hrDays
Cord Wood Boiler Coverage Daily Average Demand
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over the course of a year to offset 70% of the anticipated fuel oil use for heating the RVC offices
in the Multipurpose Building. Cribbing would be used to keep the stacked wood off of the
ground. This building is sized based on stacking the wood 6’ high, 4’ wide, and 3’ aisles to walk
between the rows.
4.2 LAUNDROMAT
An advanced combustion unit and hot water boiler capable of firing on seasoned cord wood
sized at approximately 100,000 Btu/hr of heat output is evaluated. The boiler would be
combined with approximately 1,500 gallons of thermal storage to efficiently meet the
Laundromat’s range of heating needs. This boiler size was chosen because typically it is the
smallest boiler offered by manufacturers. The boiler operator would have to take care to
charge the firebox based on expected load to ensure that the boiler does not idle and produce
excess smoke.
The building experiences two drastically different heating loads. The space heating demand for
the building is relatively small in comparison to the potential heating demand of operating all of
the laundry equipment at the same time. However, the fuel use for the laundry equipment is a
small portion of the total fuel use based on coin collection records provided by RVC. Because of
this, the heating system is sized to optimize the coverage of the space heating demand.
Due to space constraints in the building, the system will be located in a containerized system
adjacent to the Laundromat. The containerized system will include the cord wood boiler, hot
water thermal storage system, and circulation pumps. The system will interconnect using
distribution piping in a utilidor. Propylene glycol should be used as the heating fluid due to
extreme cold temperatures experience throughout the winter. Additionally, heat trace wiring
should be installed in the utilidor as a safety precaution.
The hot water thermal storage will hold approximately 335,000 Btu assuming a 60% propylene
glycol concentration, 190ᵒF storage temperature, and 160ᵒF distribution return temperature.
This would provide 3 hours and 20 minutes of load to charge the tank from 160ᵒF to 190ᵒF as
well as allow the operation of four dryers for 50 minute dry cycles with a fully charged tank.
The boiler will be over sized but is typically the smallest size available for an ASME rated cord
wood boiler. The large thermal storage tank will mitigate the effects of an oversized boiler. The
estimated coverage using the cord wood boiler for the Laundromat is shown in Figure 4.2‐1.
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Figure 4.2‐1 – Estimated Cord Wood System Coverage of Load Duration Curve
Note: The load duration curve model is based on local weather data and annual fuel delivery volumes provided by
RVC. Potential coverage of 33% is shown while estimating a minimum turndown of 40%. Actual coverage will
depend on management of loads and the use of thermal storage.
Figure 4.2‐1 shows 33% coverage of the space heating load duration curve using the cord wood
system. The existing fuel oil system in the boiler room will supplement the cord wood system
as needed. Actual coverage will vary depending on weather conditions, peak demands,
equipment operation schedules, and periods when the boilers are shut down for maintenance.
The 100,000 Btu/hr system is large for the building heating demand, but is typically the smallest
size offered by manufacturers. The coverage assumes a minimum boiler turndown of 40% with
the cord wood system. Cord wood boilers can turndown more than 40%, however efficiency
drops off quickly below this point. The 1,500 gallon thermal storage system will provide a large
buffer on the system and reduce periods operating below 40% boiler output. This report
assumes 70% coverage for the cord wood system for estimating the potential fuel use and
savings for the Laundromat.
Laundry and shower use is not included in the coverage graph. The Laundry and shower energy
use is estimated to account for 20% of the total fuel use. This portion of the load is not
consistent since laundry and shower schedules are not defined. A larger portion of the laundry
0
10,000
20,000
30,000
40,000
50,000
60,000
70,000
11223344556677889100111122133144155166177188199210221232243254265276287298309320331342353364Heating Demand, Btu/hrDays
Cord Wood Boiler Coverage Daily Average Demand
Biomass Prefeasibility Report Date: July 28, 2015 Rampart Village Council
Final
WES Energy & Environment
Page 18 of 28
and shower loads could be covered by the cord wood system if RVC provided an incentive (such
as half priced laundry) to do laundry or take showers during defined periods. RVC could then
make sure the boiler is loaded with wood and the thermal storage is charged to cover the
laundry and drying loads during these periods.
A 600 ft2 covered pole style building with walls that allow air to flow through is recommended
to store the 15.5 cords of wood that would be required over the course of a year to offset 70%
of the anticipated fuel oil use for heating the Laundromat. Cribbing would be used to keep the
stacked wood off of the ground. This building is sized based on an estimated stack height of 6’
and width of 4’ and 3’ aisles to walk between the rows.
4.3 DISTRICT SYSTEM SERVING THE MULTIPURPOSE BUILDING AND THE LAUNDROMAT
A district system that would connect to the heating systems for the RVC Offices planned for
construction in the Multipurpose Building and the Laundromat are evaluated. A containerized
cordwood boiler system would be located next to the laundromat since this would be a year
round heating load.
An advanced combustion unit and hot water boiler capable of firing on seasoned cord wood
sized at approximately 150,000 Btu/hr of heat output is evaluated. The boiler would be
combined with approximately 1,500 gallons of thermal storage to efficiently meet the range of
heating needs for both buildings. The capacity of the system will provide added flexibility of
operation for both buildings. The large volume of thermal storage will require multiple firings
per day during the coldest times of the year which will allow the boiler to maintain an efficient
firing rate during operation. The boiler operator should manage how full the firebox is charged
depending on outside air temperature, thermal storage tank temperature, and anticipated
laundry loads. A firebox sized at 23” x 16” x 28” that is fully loaded will hold approximately
635,000 Btu’s of wood assuming 80% of the volume is occupied with wood and a density of
2,500 lbs/cord, which will be able to transfer 445,000 Btu’s to the glycol heating system
assuming a 70% efficiency.
The system will interconnect to the heating systems of both buildings using insulated
distribution piping in a utilidor. Propylene glycol should be used as the heating fluid due to
extreme cold temperatures experienced throughout the winter. Additionally, heat trace wiring
should be installed in the utilidor as a safety precaution.
The hot water thermal storage will hold approximately 335,000 Btu assuming a 60% propylene
glycol concentration, 190ᵒF storage temperature, and 160ᵒF distribution return temperature.
This would provide 2 hours and 15 minutes of load to charge the tank from 160ᵒF to 190ᵒand
allow the operation of four dryers for 50 minute dry cycles with a fully charged tank. The small
increase in boiler output compared to the individual systems will provide additional flexibility
for operation and charging the system and offsetting fuel oil use. The anticipated duration of
operation below the efficient firing rate will be mitigated by the large volume of thermal
storage. The estimated coverage using the cord wood boiler for both buildings is shown in
Figure 4.3‐1.
Biomass Prefeasibility Report Date: July 28, 2015 Rampart Village Council
Final
WES Energy & Environment
Page 19 of 28
Figure 4.3‐1 – Estimated Cord Wood System Coverage of Load Duration Curve
Note: The load duration curve model is based on local weather data and annual fuel delivery volumes provided by
RVC. Potential coverage of 70% is shown while estimating a minimum turndown of 40%. Actual coverage will
depend on management of loads and the use of thermal storage.
Figure 4.3‐1 shows 70% coverage of the space heating load duration curve using the cord wood
system. The existing fuel oil system in the boiler rooms will supplement the cord wood system
as needed. Actual coverage will vary depending on weather conditions, peak demands,
equipment operation schedules, and periods when the boilers are shut down for maintenance.
This report assumes 70% coverage for estimating the potential fuel use and savings for the
district system.
Laundry and shower use is not included in the coverage graph. The Laundry and shower energy
use is estimated to account for 20% of the total fuel use. This portion of the load is not
consistent since laundry and shower schedules are not defined. A larger portion of the laundry
and shower loads could be covered by the cord wood system if RVC provided an incentive (such
as half priced laundry) to do laundry or take showers during defined periods. RVC could then
make sure the boiler is loaded with wood and the thermal storage is charged to cover the
laundry and drying loads during these periods.
0
20,000
40,000
60,000
80,000
100,000
120,000
140,000
11223344556677889100111122133144155166177188199210221232243254265276287298309320331342353364Heating Demand, Btu/hrDays
Cord Wood Boiler Coverage Daily Average Demand
Biomass Prefeasibility Report Date: July 28, 2015 Rampart Village Council
Final
WES Energy & Environment
Page 20 of 28
A 1,000 ft2 covered pole style building with walls that allow air to flow through is recommended
to store the 28.4 cords of wood that would be required over the course of a year to offset 70%
of the anticipated fuel oil use for both buildings. Cribbing would be used to keep the stacked
wood off of the ground. This building is sized based on an estimated stack height of 6’ and
width of 4’ and 3’ aisles to walk between the rows.
Additionally, the existing fuel oil boilers in both buildings seem to be very large in respect to the
anticipated heating loads. If a district system is considered for further evaluation, the heating
capacity of the Laundromat boilers may be large enough to heat both buildings. The
Multipurpose Building boilers could be abandoned in place or removed to reduce annual
maintenance and inspection costs. Further analysis should be completed to verify building
loads and if the Laundromat boilers have sufficient capacity if a district system is pursued as an
option.
5.0 BENEFIT/COST ANALYSIS
Capital costs are estimated for each option based on recent quotations and bids provided by
cord wood boiler manufacturers. These costs include a covered fuel storage building,
containerized cord wood hot water boiler system, hot water thermal storage, and installation.
The estimated capital costs are listed in Table 5.0‐1. Tables showing the detailed cost
breakdowns are found in Appendix B.
Table 5.0‐1 – Estimated Project Capital Costs
Project Description Estimated Capital Cost
1 : RVC Offices $135,556
2 : Laundromat $158,700
3 : District System $324,013
Operation and maintenance costs were estimated for each option. It is assumed that RVC
would use existing staff to load the boiler and perform maintenance as needed and additional
labor costs for maintenance are not considered. Ash removal costs are not considered since ash
can be a valuable resource to improve soil quality and is assumed to be land applied. Additional
electricity costs are estimated for each option assuming electricity costs of $0.70/kWh.
Biomass Prefeasibility Report Date: July 28, 2015 Rampart Village Council
Final
WES Energy & Environment
Page 21 of 28
Table 5.0‐2 – Estimated Annual Operating & Maintenance Costs
Item Option 1 Option 2 Option 3
Electricity $966 $1,405 $3,311
Annual Maintenance $100 $100 $100
Totals $1,066 $1,505 $3,411
Notes:
1 – Electricity costs assume 10 days of full power operation and 200 days at part load for Option 1, 6
hours a day of full power operation and 4 hours a day of part load operation for Options 2 and 3, and
an electricity price of $0.70/kWh to estimate electricity costs.
2 – Option 3 includes an additional 1 hp district pump during hours of operation.
3 – Annual maintenance costs are annualized over the lifespan of manufacturer recommended
replacement parts. Replacement is assumed by RVC staff and costs for labor are not included.
A fuel use summary was developed for each option showing the current annual oil use,
estimated offset with the cord wood system, estimated annual wood use, and estimated annual
oil use to supplement the wood system. Table 5.0‐3 shows the estimated annual fuel use
summary.
Table 5.0‐3 – Estimated Annual Fuel Use Summary
Option
Estimated
Current
Annual Oil
Use, Gallons
Estimated
Offset with
Cord Wood
System
Estimated
Annual Cord
Wood Use,
Cords
Estimated Annual
Fuel Oil Use with
Cord Wood
System, Gallons
1 : RVC Offices 2,040 70% 12.9 612
2 : Laundromat 2,450 70% 15.5 735
3 : District System 4,490 70% 28.4 1,347
Annual operating savings are estimated considering fuel costs and O&M costs. Table 5.0‐4
shows the estimated annual operating savings for each option.
Table 5.0‐4 – Estimated Annual Operating Savings
Option
Current
Annual
Fuel Oil
Cost
Estimated Costs and Savings with Cord Wood System
Estimated
Annual Cord
Wood Cost
Estimated
Annual Oil
Cost with Cord
Wood System
Estimated
Annual O&M
Costs
Estimated
Annual
Savings
1 : RVC Offices $13,257 $3,870 $3,978 $1,066 $4,343
2 : Laundromat $15,925 $4,650 $4,778 $1,505 $4,992
3 : District System $29,182 $8,520 $8,756 $3,411 $8,495
Biomass Prefeasibility Report Date: July 28, 2015 Rampart Village Council
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WES Energy & Environment
Page 22 of 28
A benefits summary is listed in Table 5.0‐5 showing the estimated capital cost, 1st year net
operating savings, simple payback, 20 year Net Present Value, and 20 Year Benefits to Cost
(B/C) ratio.
Table 5.0‐5 – Cost and Benefit Summary
Option Estimated
Capital Cost
1st Year Net
Annual Operating
Savings
Simple
Payback,
Years
20 Year Net
Present
Value
20 Year
B/C Ratio
1 : RVC Offices $135,556 $4,343 31.2 $ (50,621) 0.63
2 : Laundromat $158,700 $4,992 31.8 $ (61,031) 0.62
3 : District System $324,013 $8,495 38.1 $ (157,704) 0.51
Notes:
1 – Net Annual Operating Savings include costs for wood fuel, supplemental fossil fuel, and operation &
maintenance (O&M) costs.
2 – 20 Year Net Present Value takes the present value of the operating savings for each year using a nominal
discount rate of 3.1% as published in the “Energy Price Indices and Discount Factors for Life‐Cycle Cost Analysis ‐
2014” and the initial capital outlay of the total project cost. A value greater than zero means that savings are
greater than expenses over 20 years in the value of today’s dollars.
3 – 20 Year Benefit/Cost (B/C) Ratio is calculated by dividing the present value of net annual operating savings over
a 20 year period with a discount rate of 3.1% by the Estimated Capital Cost. A value greater than 1 means the
benefits exceed the costs over a 20 year period.
A cash flow analysis was completed for financing the projects assuming a 20 year financing term
at a 4.0% interest rate. None of the Options had a positive first year cash flow after annual
payments. First year cash flow for all three options would break even or be slightly positive with
65% grant funding of project costs. The detailed analyses are shown in Appendix C. Table 5.0‐6
lists the assumptions and values used to develop costs and savings in this study.
Table 5.0‐6 – Assumptions and Values Used in the Report
Item Value and Unit Source
Cord wood moisture content, wet basis 20%WES E&E assumption
#1 Fuel oil high heating value 134,000 Btu/gal WES E&E assumption
High heating value of 50/50 mix of White Spruce (18.1
mmBtu/cord) and Black Spruce (15.9 mmBtu/cord) 17.0 mmBtu/Cord University of Alaska Fairbanks
Cooperative Extension Service
#1 Fuel oil boiler efficiency (HHV) 80%WES E&E assumption
Cord wood gasification boiler efficiency (HHV)70%WES E&E assumption
RVC Offices oil offset with cord wood system 70%WES E&E assumption
Laundromat oil offset with cord wood system 70%WES E&E assumption
District system oil offset with cord wood system 70%WES E&E assumption
Electricity price $0.70/kWh WES E&E assumption
#1 Fuel oil price $6.50/gallon RVC
Cord wood price $300/cord RVC
#1 Fuel oil inflation rate 3.1%NISTIR 85‐3273‐29
O&M inflation rate 3.0%WES E&E assumption
Cord wood inflation rate 3.0%WES E&E assumption
Discount rate 3.1%NISTIR 85‐3273‐29
Biomass Prefeasibility Report Date: July 28, 2015 Rampart Village Council
Final
WES Energy & Environment
Page 23 of 28
6.0 CONCLUSIONS & RECOMMENDATIONS
This study concludes that Rampart Village Council can reduce annual operating costs for space
heating and laundry services by installing a high efficiency, low emission cord wood boiler
system. Based on the current economics, capital costs may be too high for RVC to justify
proceeding with a project. The proposed systems will offset 70% of the current fuel oil use for
space heating, laundry, and domestic hot water at capital costs ranging from ~$135,000 ‐
~$325,000 depending on the option selected. This would provide Rampart Village Council with
net operating savings ranging from ~$4,000 to ~$8,500 in the first year of operation. If 75% of
the project costs were funded through grants, the simple payback for RVC funds would range
from 8 ‐ 10 years for the proposed options. Additional benefits that would be provided by
proceeding with a project include:
Purchase of cord wood will immediately impact the local economy;
Decreased dependence on fossil fuels by replacing 1,500 to 3,150 gallons of #1 fuel oil
with renewable biomass fuel;
A hedge against volatility of the fossil fuel market;
As Rampart Village Council continues to pursue biomass energy options, WES Energy &
Environment recommends that the next level of evaluation includes detailed consideration of
the following items:
Siting of the biomass plant and covered cord wood storage area.
Biomass system capital costs based on detailed site investigations, initial plant layout
and design, and direct quotes from manufacturers.
Alternative funding sources (low interest loans, grants, and incentives).
Evaluate in further detail the potential to interconnect the Multipurpose Building and
Laundromat heating systems and use the Laundromat boiler for heating both buildings.
Capital avoidance costs for not refurbishing the Multipurpose Building boilers if the
Laundromat boilers are used for heating.
Acceptable district piping routes between evaluated buildings.
The potential to install a bypass, lint trap, and alternate dryer vent discharge into the
Laundromat. The bypass damper could be controlled by a humidistat in the laundromat.
This would reduce the heating demand of the building by recovering the heat from the
dryer exhaust.
Biomass Prefeasibility Report Date: July 28, 2015 Rampart Village Council
Final
WES Energy & Environment
Page 24 of 28
Source:
http://www.epa.gov/burnwise/woodstoves.ht
ml
Source:
http://www.forgreenheat.org/consumer_reso
urces/reliablepellet.html
7.0 GENERAL BIOMASS TECHNOLOGY INFORMATION
This section describes technologies that can be used for efficiently using wood for space
heating and domestic hot water heating. Manufacturers of each technology are available both
domestically and abroad. A partial list of manufacturers is provided for technologies and does
not constitute an endorsement. Other manufacturers are available and individual
investigations should be completed prior to purchase. Local codes and regulations may require
modifications or additional components for compliance depending on the system considered.
High Efficiency Catalytic Wood Stoves
High efficiency catalytic wood stoves can be used to
heat spaces efficiently using cord wood. They are
typically used for smaller buildings and rooms with
open layouts. The catalytic element reburns the smoke
to increase efficiency and reduce air emissions.
Efficiencies can reach 70% and higher. Equipment costs
can range from $4,000 to $6,000 plus installation.
Annual savings can range from $3,000 to $5,000 per
year based on a facility using 1,500 gallons of propane
per year at current prices. Catalytic elements will
require periodic replacement every 5‐7 years depending
on frequency of use and will cost $200 ‐ $400 for the
replacement element. Wood loading and ash removal
is manual. A partial list of manufacturers include
Woodstock Soapstone, Blaze King, Vermont Castings,
and Lopi.
Wood Pellet Stoves
High efficiency wood pellet stoves can be used to heat
spaces efficiently using wood pellets. They are typically
used for smaller buildings and rooms with open layouts.
Efficiencies can reach 80% and higher. Equipment costs
can range from $4,000 to $7,000 plus installation.
Annual savings can range from $1,500 to $2,500 per
year based on a facility using 1,500 gallons of propane
per year at current prices. Fuel loading and ash removal
is manual. A partial list of manufacturers include
England Stove Works, Sherwood Industries, Harman,
and Lopi.
Biomass Prefeasibility Report Date: July 28, 2015 Rampart Village Council
Final
WES Energy & Environment
Page 25 of 28
Source:
http://www.woodboilers.com/products/pellet‐
boilers/froling‐p4‐pellet.html
High Efficiency Indoor Wood Pellet Boiler
High efficiency indoor wood pellet boilers utilize
premium wood pellets as a renewable biomass fuel
source for hot water space heating systems. Wood
pellets are automatically fed from an adjacent storage
hopper into the firebox based on heating demand.
Efficiencies can exceed 80% when coupled with a hot
water thermal storage system that allows the boiler to
operate at high fire to charge the hot water thermal
storage tank. Multiple boilers can be operated to
increase heating capacity. Equipment costs can vary
depending on the heating capacity required. Annual
savings can range from $3,000 to $6,000 per year based
on a facility using 5,000 gallons of #1 fuel oil per year at
current prices. Manual and automatic hopper loading is
available. Ash removal is manual. A partial list of
manufacturers include ACT Bioenergy, Froling, MESys,
Evo World, Windhager, Kedel, and Wood Master.
High Efficiency Indoor Cord Wood Boiler
High efficiency indoor cordwood boilers utilize split
cordwood as a renewable biomass fuel source for hot
water space heating systems. Efficiencies can exceed
70% when coupled with a hot water thermal storage
system that allows the cordwood boiler to operate at
high fire to charge the hot water thermal storage tank.
Equipment costs can range from $7,000 to $15,000 plus
installation. Annual savings can range from $1,800 to
$2,200 per year based on an average building using
1,500 gallons of #1 fuel oil per year at current prices.
Manual loading and ash removal are required. A partial
list of manufacturers include Wood Gun, Econoburn,
Froling, Windhager, and Wood Master.
Source:
http://www.woodboilers.com/product
s/woodboilers/froeling‐fhg.html
Biomass Prefeasibility Report Date: July 28, 2015 Rampart Village Council
Final
WES Energy & Environment
Page 26 of 28
Source:
http://www.afsenergy.com/Biomass%20Energy.htm
Advanced Biomass Combustion Units and Boilers
Advanced biomass combustion units and boilers are
typically an engineered product capable of firing on
wood chips, saw mill residue, wood pellets, and saw
dust. Fuel is typically delivered in bulk semi‐trailer
loads and automatically conveyed to the
combustion unit. Efficiencies can exceed 70% when
coupled with a hot water thermal storage system.
Emission controls are typically required to clean up
exhaust gasses. Capital costs are high and vary
depending on many factors. Annual fuel cost savings
can range from $100,000 to $120,000 per year
based on a facility using 50,000 gallons of #1 fuel oil
per year at current prices. High fuel costs and high
fuel usage can potentially make a project feasible. A
partial list of manufacturers include Viessman, ACT
Bioenergy, Froling, MESys, Evo World, Wood
Master, Messersmith Manufacturing, AFS Energy
Systems, Solagen, Wellons FEI, and Hurst.
Hot Water Thermal Storage System
Thermal storage tanks, also known as accumulator
tanks or buffer tanks, can raise the efficiency of hot
water heating systems firing on wood. Solid fuels
burn more efficiently at higher firing rates than at
lower rates or idle modes where the fuel smolders,
smokes, and wastes energy. Hot water thermal
storage allows the solid fuel boiler to fire efficiently
at full output to store the heat at elevated
temperatures in storage tanks. For optimum
operation a mixing valve is installed to blend cold
water returning from the facility with hot water
stored in the thermal storage tank. Hot water is
sent back to the facility at a temperature that is
lower than the storage tanks, providing heat storage
and a buffer for short periods of high demand. This
method of operation reduces smoldering and
smoking from inefficient operation, fuel use,
creosote buildup, and the need for frequent stoking.
Source:
http://www.viessmann‐
us.com/en/District_Heating/Products/dhw/Storag
e_Tanks.html
Biomass Prefeasibility Report Date: July 28, 2015 Rampart Village Council
Final
WES Energy & Environment
Page 27 of 28
Source:
WES Energy & Environment File Photo
District Piping Systems
It can often be cost effective to connect multiple
buildings to one central wood fired heating plant.
Long runs of buried piping can be installed cost
effectively using pre‐insulated PEX piping. It is
important to use factory injected close cell foam
insulation with a High Density Polyethylene (HDPE)
insulation jacket to prevent the insulation from being
compromised from ground water or leaks. Pipe sizes
can range from 3/4” to 5” with roll lengths up to 600
feet. Pipe material costs can be more expensive than
traditional iron pipe, however installation costs can
be reduced due to longer runs between splices and
connections.
Biomass Prefeasibility Report Date: July 28, 2015 Rampart Village Council
Final
WES Energy & Environment
Appendix A
Conceptual Drawings
100,000 BTU/hrCord Wood BoilerStackSCALE5'0'2.5' 5'Notes1. This drawing is a conceptual layout for the purposesof showing one option for layout of a biomass system.Final design and layout will change based onequipment selected, designer, and site conditions.Approx. 20'-0"800 GallonThermal StorageTankApprox. 8'-0"Multi PurposeBuilding600 Sq. Ft. CordWood StorageWESEE Proposed Biomass
Rampart Village, AK
Option 1 Plan View
SCALE10'0'5' 10'600 Sq. Ft. CordWood Storage150,000 BTU/hrCord Wood BoilerStackThermal Storage Tanks1,500 Gallon TotalClinicLaundryFacilityApprox. 20'-0"Ap
p
r
o
x
.
1
6
'
-
0
"20'-0"30'
-
0
"Notes1. This drawing is a conceptual layout for the purposesof showing one option for layout of a biomass system.Final design and layout will change based onequipment selected, designer, and site conditions.WESEE Proposed Biomass
Rampart Village, AK
Option 2 Plan View
1,000 Sq. Ft. CordWood StorageSCALE10'0'5' 10'150,000 BTU/hrCord Wood BoilerStackThermal Storage Tanks1,500 Gallon TotalClinicLaundryFacilityApprox. 20'-0"Ap
p
r
o
x
.
1
6
'
-
0
"Notes1. This drawing is a conceptual layout for the purposesof showing one option for layout of a biomass system.Final design and layout will change based onequipment selected, designer, and site conditions.20'-0"50'
-
0
"
WESEE Proposed Biomass
Rampart Village, AK
Option 3 Plan View
SCALE50'0'25' 50'Notes1. This drawing is a conceptual layout for the purposesof showing one option for layout of a biomass system.Final design and layout will change based onequipment selected, designer, and site conditions.Containerized UnitLaundry FacilityMulti Purpose buildingCord WoodStorageWESEE Proposed Biomass
Rampart Village, AK
Option 3 Site Plan
Biomass Prefeasibility Report Date: July 28, 2015 Rampart Village Council
Final
WES Energy & Environment
Appendix B
Preliminary Capital Cost Estimates
Appendix B Rampart Village Council
Line Item Cost
One (1) ‐ 100,000 Btu/hr cord wood boiler, freight, containerized, and installed 45,000$
Stick frame storage building with cribbing floor to stack wood, 500 ft2 @ $25/ft2 12,500$
Thermal storage 800 gallon with insulation 15,000$
Inhibited Propylene Glycol 10,000$
Interconnection with existing boiler room, pumps, installation 10,000$
Electrical 5,000$
Mechanical 5,000$
Sub‐Total 102,500$
Contingency 15%15,375$
Sub‐Total 117,875$
Profesional Services 15%17,681$
Total 135,556$
Notes:
3 ‐ Estimate is based on competitive bidding.
Option 1 ‐ Cord Wood Boiler System for RVC Offices in
the Multipurpose Building
1 ‐ The boiler system is to be installed next to the existing boiler room. Pricing is based on a one‐boiler
solution. There are multiple manufacturers that can provide varying boiler sizes. Other boiler sizing
combinations to meet a similar output range may also be selected.
2 ‐ Professional Services includes permitting, legal, engineering, & project management. (Assumed that
minimal engineering is required.)
WES Energy & Environment B.1
Appendix B Rampart Village Council
Line Item Cost
One (1) ‐ 100,000 Btu/hr cord wood boiler, freight, containerized, and installed 45,000$
Stick frame storage building with cribbing floor to stack wood, 600 ft2 @ $25/ft2 15,000$
Thermal storage 1,500 gallon with insulation 20,000$
Inhibited Propylene Glycol 20,000$
Interconnection with existing boiler room, pumps, installation 10,000$
Electrical 5,000$
Mechanical 5,000$
Sub‐Total 120,000$
Contingency 15%18,000$
Sub‐Total 138,000$
Profesional Services 15%20,700$
Total 158,700$
Notes:
3 ‐ Estimate is based on competitive bidding.
Option 2 ‐ Cord Wood Boiler System for Laundromat
1 ‐ The boiler system is to be installed next to the existing boiler room. Pricing is based on a one‐boiler
solution. There are multiple manufacturers that can provide varying boiler sizes. Other boiler sizing
combinations to meet a similar output range may also be selected.
2 ‐ Professional Services includes permitting, legal, engineering, & project management. (Assumed that
minimal engineering is required.)
WES Energy & Environment B.2
Appendix B Rampart Village Council
Line Item Cost
One (1) ‐ 150,000 Btu/hr cord wood boiler, freight, containerized, and installed 50,000$
Stick frame storage building with cribbing floor to stack wood, 1,000 ft2 @ $25/ft2 25,000$
Thermal storage 1,500 gallon with insulation 20,000$
Inhibited Propylene Glycol 20,000$
360 linear feet of 1.5" utilidor district piping to Laundry & Multipurpose Building @ $250/lf 90,000$
Interconnection with both boiler rooms, pumps, installation 20,000$
Electrical 10,000$
Mechanical 10,000$
Sub‐Total 245,000$
Contingency 15%36,750$
Sub‐Total 281,750$
Profesional Services 15%42,263$
Total 324,013$
Notes:
3 ‐ Estimate is based on competitive bidding.
Option 3 ‐ District Cord Wood Boiler System for Laundromat & RVC
Offices in the Multipurpose Building
1 ‐ The boiler system is to be installed between the Multipurpose Building and the Laundromat. Pricing is
based on a one‐boiler solution. There are multiple manufacturers that can provide varying boiler sizes. Other
boiler sizing combinations to meet a similar output range may also be selected.
2 ‐ Professional Services includes permitting, legal, engineering, & project management. (Assumed that
minimal engineering is required.)
WES Energy & Environment B.3
Biomass Prefeasibility Report Date: July 28, 2015 Rampart Village Council
Final
WES Energy & Environment
Appendix C
20 Year Financing at 4% APR Cash Flow Analysis
Appendix COption 1 ‐ Cord Wood Boiler System for RVC Offices in the Multipurpose Building20 Year, 4% FinancingRampart Village CouncilInput VariablesValue Units Year #1 Fuel Oil Cost, Current System Cord Wood Cost #1 Fuel Oil Cost, w/ Wood System Added O&M Cost Net Operating Savings Annual Financing Payment Net Cash Flow Present Value of Cash Flow Project Costs Financed135,556 $1 13,257$ (3,870)$ (3,978)$ (1,066)$ 4,343$ (9,974)$ (5,632)$ (5,462)$ Financing Term20 # years 2 13,668$ (3,986)$ (4,101)$ (1,099)$ 4,481$ (9,974)$ (5,493)$ (5,168)$ Financing Rate (apr)4.0% Percent 3 14,092$ (4,106)$ (4,228)$ (1,133)$ 4,624$ (9,974)$ (5,350)$ (4,882)$ Current #1 Fuel Oil Usage2,040 gal 4 14,528$ (4,229)$ (4,360)$ (1,168)$ 4,772$ (9,974)$ (5,203)$ (4,605)$ Year 1 #1 Fuel Oil Average Price$6.50 $/gal 5 14,979$ (4,356)$ (4,495)$ (1,204)$ 4,924$ (9,974)$ (5,050)$ (4,336)$ Proposed Annual Cord Wood Usage12.9 Cords/yr 6 15,443$ (4,486)$ (4,634)$ (1,242)$ 5,081$ (9,974)$ (4,893)$ (4,074)$ Year 1 Cord Wood Purchase Price$300 $/Cord 7 15,922$ (4,621)$ (4,778)$ (1,280)$ 5,243$ (9,974)$ (4,731)$ (3,821)$ Annual #1 Fuel Oil Usage w/ Wood System612 gal/yr 8 16,416$ (4,760)$ (4,926)$ (1,320)$ 5,410$ (9,974)$ (4,564)$ (3,575)$ Fossil Fuel Inflation Rate (apr)3.1% Percent 9 16,924$ (4,902)$ (5,078)$ (1,361)$ 5,583$ (9,974)$ (4,392)$ (3,337)$ Cord Wood Inflation Rate (apr)3.0% Percent 10 17,449$ (5,049)$ (5,236)$ (1,403)$ 5,761$ (9,974)$ (4,214)$ (3,105)$ O&M Inflation Rate3.0% Percent 11 17,990$ (5,201)$ (5,398)$ (1,447)$ 5,944$ (9,974)$ (4,030)$ (2,881)$ Discount Rate (apr)3.1% Percent 12 18,548$ (5,357)$ (5,566)$ (1,491)$ 6,134$ (9,974)$ (3,841)$ (2,663)$ Added Annual O&M Costs for Biomass Plant $1,066 $/yr 13 19,123$ (5,518)$ (5,738)$ (1,538)$ 6,329$ (9,974)$ (3,645)$ (2,451)$ 14 19,715$ (5,683)$ (5,916)$ (1,585)$ 6,531$ (9,974)$ (3,444)$ (2,246)$ 15 20,327$ (5,854)$ (6,099)$ (1,634)$ 6,739$ (9,974)$ (3,235)$ (2,047)$ 16 20,957$ (6,029)$ (6,288)$ (1,685)$ 6,954$ (9,974)$ (3,021)$ (1,853)$ 17 21,606$ (6,210)$ (6,483)$ (1,737)$ 7,175$ (9,974)$ (2,799)$ (1,666)$ 18 22,276$ (6,397)$ (6,684)$ (1,791)$ 7,404$ (9,974)$ (2,570)$ (1,484)$ 19 22,967$ (6,588)$ (6,892)$ (1,847)$ 7,640$ (9,974)$ (2,334)$ (1,307)$ 20 23,679$ (6,786)$ (7,105)$ (1,904)$ 7,883$ (9,974)$ (2,091)$ (1,136)$ Present Value (62,097)$ WES Energy & EnvironmentC.1
Appendix COption 2 ‐ Cord Wood Boiler System for Laundromat20 Year, 4% FinancingRampart Village CouncilInput VariablesValue Units Year #1 Fuel Oil Cost, Current System Cord Wood Cost #1 Fuel Oil Cost, w/ Wood System Added O&M Cost Net Operating Savings Annual Financing Payment Net Cash Flow Present Value of Cash Flow Project Costs Financed158,700 $1 15,925$ (4,650)$ (4,778)$ (1,505)$ 4,992$ (11,677)$ (6,685)$ (6,484)$ Financing Term20 # years 2 16,419$ (4,790)$ (4,926)$ (1,552)$ 5,152$ (11,677)$ (6,526)$ (6,139)$ Financing Rate (apr)4.0% Percent 3 16,928$ (4,933)$ (5,078)$ (1,600)$ 5,316$ (11,677)$ (6,361)$ (5,805)$ Current #1 Fuel Oil Usage2,450 gal4 17,452$ (5,081)$ (5,236)$ (1,650)$ 5,486$ (11,677)$ (6,192)$ (5,480)$ Year 1 #1 Fuel Oil Average Price$6.50 $/gal 5 17,993$ (5,234)$ (5,398)$ (1,701)$ 5,661$ (11,677)$ (6,016)$ (5,165)$ Proposed Annual Cord Wood Usage16 Cords/yr 6 18,551$ (5,391)$ (5,565)$ (1,753)$ 5,842$ (11,677)$ (5,836)$ (4,859)$ Year 1 Cord Wood Purchase Price$300 $/Cord 7 19,126$ (5,552)$ (5,738)$ (1,808)$ 6,028$ (11,677)$ (5,649)$ (4,562)$ Annual #1 Fuel Oil Usage w/ Wood System735 gal/yr 8 19,719$ (5,719)$ (5,916)$ (1,864)$ 6,221$ (11,677)$ (5,457)$ (4,274)$ Fossil Fuel Inflation Rate (apr)3.1% Percent 9 20,331$ (5,890)$ (6,099)$ (1,922)$ 6,419$ (11,677)$ (5,258)$ (3,995)$ Cord Wood Inflation Rate (apr)3.0% Percent 10 20,961$ (6,067)$ (6,288)$ (1,981)$ 6,624$ (11,677)$ (5,053)$ (3,724)$ O&M Inflation Rate3.0% Percent 11 21,611$ (6,249)$ (6,483)$ (2,043)$ 6,836$ (11,677)$ (4,842)$ (3,461)$ Discount Rate (apr)3.1% Percent 12 22,280$ (6,437)$ (6,684)$ (2,106)$ 7,054$ (11,677)$ (4,624)$ (3,205)$ Added Annual O&M Costs for Biomass Plant $1,505 $/yr 13 22,971$ (6,630)$ (6,891)$ (2,171)$ 7,279$ (11,677)$ (4,399)$ (2,958)$ 14 23,683$ (6,829)$ (7,105)$ (2,239)$ 7,511$ (11,677)$ (4,166)$ (2,717)$ 15 24,417$ (7,034)$ (7,325)$ (2,308)$ 7,751$ (11,677)$ (3,927)$ (2,484)$ 16 25,174$ (7,245)$ (7,552)$ (2,380)$ 7,998$ (11,677)$ (3,679)$ (2,258)$ 17 25,955$ (7,462)$ (7,786)$ (2,453)$ 8,253$ (11,677)$ (3,424)$ (2,038)$ 18 26,759$ (7,686)$ (8,028)$ (2,529)$ 8,517$ (11,677)$ (3,161)$ (1,825)$ 19 27,589$ (7,916)$ (8,277)$ (2,608)$ 8,788$ (11,677)$ (2,889)$ (1,618)$ 20 28,444$ (8,154)$ (8,533)$ (2,689)$ 9,069$ (11,677)$ (2,609)$ (1,417)$ Present Value (74,466)$ WES Energy & EnvironmentC.2
Appendix COption 3 ‐ District Cord Wood Boiler System for Laundromat &RVC Offices in the Multipurpose Building20 Year, 4% FinancingRampart Village CouncilInput VariablesValue Units Year #1 Fuel Oil Cost, Current System Cord Wood Cost #1 Fuel Oil Cost, w/ Wood System Added O&M Cost Net Operating Savings Annual Financing Payment Net Cash Flow Present Value of Cash Flow Project Costs Financed324,013 $1 29,182$ (8,520)$ (8,756)$ (3,411)$ 8,495$ (23,841)$ (15,346)$ (14,885)$ Financing Term20 # years 2 30,087$ (8,776)$ (9,027)$ (3,517)$ 8,767$ (23,841)$ (15,074)$ (14,181)$ Financing Rate (apr)4.0% Percent 3 31,019$ (9,039)$ (9,307)$ (3,626)$ 9,048$ (23,841)$ (14,794)$ (13,499)$ Current #1 Fuel Oil Usage4,490 gal4 31,981$ (9,310)$ (9,595)$ (3,738)$ 9,337$ (23,841)$ (14,504)$ (12,837)$ Year 1 #1 Fuel Oil Average Price$6.50 $/gal 5 32,972$ (9,589)$ (9,893)$ (3,854)$ 9,636$ (23,841)$ (14,206)$ (12,195)$ Proposed Annual Cord Wood Usage28 Cords/yr 6 33,994$ (9,877)$ (10,199)$ (3,974)$ 9,944$ (23,841)$ (13,897)$ (11,571)$ Year 1 Cord Wood Purchase Price$300 $/Cord 7 35,048$ (10,173)$ (10,516)$ (4,097)$ 10,262$ (23,841)$ (13,579)$ (10,966)$ Annual #1 Fuel Oil Usage w/ Wood System1,347 gal/yr 8 36,135$ (10,479)$ (10,842)$ (4,224)$ 10,591$ (23,841)$ (13,251)$ (10,379)$ Fossil Fuel Inflation Rate (apr)3.1% Percent 9 37,255$ (10,793)$ (11,178)$ (4,355)$ 10,929$ (23,841)$ (12,912)$ (9,810)$ Cord Wood Inflation Rate (apr)3.0% Percent 10 38,410$ (11,117)$ (11,524)$ (4,490)$ 11,279$ (23,841)$ (12,562)$ (9,257)$ O&M Inflation Rate3.0% Percent 11 39,601$ (11,450)$ (11,881)$ (4,629)$ 11,640$ (23,841)$ (12,202)$ (8,721)$ Discount Rate (apr)3.1% Percent 12 40,828$ (11,794)$ (12,250)$ (4,773)$ 12,012$ (23,841)$ (11,829)$ (8,201)$ Added Annual O&M Costs for Biomass Plant $3,411 $/yr 13 42,094$ (12,147)$ (12,629)$ (4,921)$ 12,396$ (23,841)$ (11,445)$ (7,696)$ 14 43,399$ (12,512)$ (13,021)$ (5,073)$ 12,793$ (23,841)$ (11,049)$ (7,206)$ 15 44,744$ (12,887)$ (13,425)$ (5,230)$ 13,202$ (23,841)$ (10,640)$ (6,731)$ 16 46,131$ (13,274)$ (13,841)$ (5,393)$ 13,624$ (23,841)$ (10,218)$ (6,269)$ 17 47,561$ (13,672)$ (14,270)$ (5,560)$ 14,060$ (23,841)$ (9,782)$ (5,821)$ 18 49,036$ (14,082)$ (14,712)$ (5,732)$ 14,509$ (23,841)$ (9,332)$ (5,387)$ 19 50,556$ (14,505)$ (15,168)$ (5,910)$ 14,973$ (23,841)$ (8,869)$ (4,965)$ 20 52,123$ (14,940)$ (15,639)$ (6,093)$ 15,452$ (23,841)$ (8,390)$ (4,556)$ Present Value (185,134)$ WES Energy & EnvironmentC.3
Biomass Prefeasibility Report Date: July 28, 2015 Rampart Village Council
Final
WES Energy & Environment
Appendix D
Sensitivity Analysis of Estimated Annual Operating Savings
to Oil and Biomass Fuel Prices
Appendix DOption 1 ‐ Cord Wood Boiler System for RVC Offices in the Multipurpose BuildingFirst Year Net Operating Savings Sensitivity AnalysisRampart Village Council4,343$ $5.00 $5.50 $6.00 $6.50 $7.00 $7.50 $8.00 $8.50$225$3,169 $3,883 $4,597 $5,310 $6,024 $6,738 $7,452 $8,166$250$2,847 $3,560 $4,274 $4,988 $5,702 $6,415 $7,129 $7,843$275$2,524 $3,238 $3,952 $4,665 $5,379 $6,093 $6,807 $7,521$300$2,202 $2,915 $3,629 $4,343 $5,057 $5,770 $6,484 $7,198$325$1,879 $2,593 $3,307 $4,020 $4,734 $5,448 $6,162 $6,876$350$1,557 $2,270 $2,984 $3,698 $4,412 $5,125 $5,839 $6,553$375$1,234$1,948 $2,662 $3,375 $4,089 $4,803 $5,517 $6,231*Note: Excludes financing costs.Price of Fuel Oil per GallonPrice of Cord Wood per CordWES Energy & EnvironmentD.1
Appendix DOption 2 ‐ Cord Wood Boiler System for LaundromatFirst Year Net Operating Savings Sensitivity AnalysisRampart Village Council4,992$ $5.00 $5.50 $6.00 $6.50 $7.00 $7.50 $8.00 $8.50$225$3,582 $4,440 $5,297 $6,155 $7,012 $7,870 $8,727 $9,585$250$3,195 $4,052 $4,910 $5,767 $6,625 $7,482 $8,340 $9,197$275$2,807 $3,665 $4,522 $5,380 $6,237 $7,095 $7,952 $8,810$300$2,420 $3,277 $4,135 $4,992 $5,850 $6,707 $7,565 $8,422$325$2,032 $2,890 $3,747 $4,605 $5,462 $6,320 $7,177 $8,035$350$1,645 $2,502 $3,360 $4,217 $5,075 $5,932 $6,790 $7,647$375$1,257 $2,115 $2,972 $3,830$4,687 $5,545 $6,402 $7,260*Note: Excludes financing costs.Price of Fuel Oil per GallonPrice of Cord Wood per CordWES Energy & EnvironmentD.2
Appendix DOption 3 ‐ District Cord Wood Boiler System for Laundromat &RVC Offices in the Multipurpose BuildingFirst Year Net Operating Savings Sensitivity AnalysisRampart Village Council8,495$ $5.00 $5.50 $6.00 $6.50 $7.00 $7.50 $8.00 $8.50$225$5,911 $7,483 $9,054 $10,625 $12,196 $13,768 $15,339 $16,910$250$5,201 $6,773 $8,344 $9,915 $11,486 $13,058 $14,629 $16,200$275$4,491 $6,063 $7,634 $9,205 $10,776 $12,348 $13,919 $15,490$300$3,781 $5,353 $6,924 $8,495 $10,066 $11,638 $13,209 $14,780$325$3,071 $4,643 $6,214 $7,785 $9,356 $10,928 $12,499 $14,070$350$2,361 $3,933 $5,504 $7,075 $8,646 $10,218 $11,789 $13,360$375$1,651 $3,223 $4,794$6,365 $7,936$9,508 $11,079 $12,650*Note: Excludes financing costs.Price of Fuel Oil per GallonPrice of Cord Wood per CordWES Energy & EnvironmentD.3