HomeMy WebLinkAboutHigh Efficiency Low Emission Wood Fired Heat Great Lands Christian Version Final 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:
Great Lands ChrisƟan Church—Gateway to the ArcƟc
In Partnership with :
Fairbanks Economic Development CorporaƟon
Alaska Wood Energy Development Task Group
Prepared By:
Biomass Prefeasibility Report Date: July 28, 2015 Great Lands Christian Church
Final Gateway to the Artic
WES Energy & Environment
Table of Contents
1.0 Executive Summary .............................................................................................................. 1
2.0 Existing Fuel Usage & Heating Systems ............................................................................... 2
2.1 Ted’s Shed ........................................................................................................................ 2
2.2 Cabins ............................................................................................................................... 5
3.0 Forest Resource and Fuel Availability .................................................................................. 8
4.0 Proposed Biomass Systems.................................................................................................. 9
4.1 Ted’s Shed Heating System .............................................................................................. 9
4.2 Cabin Biomass Heating System ...................................................................................... 10
5.0 Benefit/Cost Analysis ......................................................................................................... 10
6.0 Conclusions & Recommendations ..................................................................................... 13
7.0 General Biomass Technology Information ........................................................................ 14
Appendix A – Conceptual Drawings
Appendix B – Capital Cost Estimates
Appendix C – AkWarm Reports
Biomass Prefeasibility Report Date: July 28, 2015 Great Lands Christian Church
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1.0 EXECUTIVE SUMMARY
This preliminary feasibility study evaluates biomass heating for Great Lands Christian Church
(GLCC) to utilize high efficiency low emission wood fired technologies at the Gateway to the
Arctic Camp located near Talkeetna, Alaska. Installation of a wood fired heating system would
present GLCC with the opportunity to reduce operating costs and utilize a renewable fuel for
heating. The camp is currently under construction and is located off of George Parks Highway
near the railroad tracks west of Talkeetna Spur Road.
There are currently 4 cabins constructed that include separate sleeping quarters and a shared
attic loft. Additionally, Ted’s Shed is under construction and is currently being used to store
construction materials. Table ES‐1 shows the buildings evaluated in this study, the building
footprints, and current source of heat.
Table ES1 – GLCC Gateway to the Arctic Building Summary
Building Square Footage Stories Heating System Heating Fuel
Ted's Shed 1,056 1 30,000 Btu/hr Garage Heater Propane
Cabin 1 768 2 Two ‐ 9,000 Btu/hr space heaters Propane
Cabin 2 768 2 Two ‐ 9,000 Btu/hr space heaters Propane
Cabin 3 768 2 Two ‐ 9,000 Btu/hr space heaters Propane
Cabin 4 768 2 Two ‐ 9,000 Btu/hr space heaters Propane
GLCC does not have historic fuel use data since the buildings are under construction or recently
completed. Additionally, the camp will be unoccupied for much of the winter and planned
usage schedules are currently unknown. Therefore, potential fuel use and costs will vary.
Catalytic wood stoves are recommended as the preferred biomass option in the 5 buildings.
Capital costs for installing catalytic wood stoves in all 5 buildings are listed in Table ES‐2. A
detailed breakdown of costs are provided in Appendix B.
Table ES2 – Estimated Project Capital Costs
Project Description Estimated
Capital Cost
5 catalytic wood stoves for 4 cabins
and Ted’s Shed installed by GLCC $25,025
Historic fuel use is unavailable and planned frequency of use during the heating season is
unknown. However, one cord of seasoned split birch is approximately equivalent to 40 full 20
lb tanks of propane factoring in equipment efficiency. Purchase of 40 tanks of propane would
cost approximately $695 based on propane pricing provided by GLCC. This would compare to
$250 for a cord of birch purchased from local wood suppliers or no cost other than labor if GLCC
wood resources were used.
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2.0 EXISTING FUEL USAGE & HEATING SYSTEMS
The five buildings evaluated in this study are recently constructed or currently under
construction. The four cabins were finished this year and Ted’s Shed was being completed
during the site visit. The camp is not connected to the electric grid, however the buildings are
wired for potential connection to generators or future connection to the grid. This section
provides detailed information about the 5 buildings evaluated in this study.
2.1 TED’S SHED
Ted’s Shed is a building that is currently being completed. It is stick framed construction with a
steel roof. The floor plan is open and can be used for meetings and activities. Figures 2.1‐1
through 2.1‐4 show the construction of Ted’s Shed.
Figure 2.1‐1 – Ted’s Shed Exterior
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Figure 2.1‐2 – Ted’s Shed Exterior
Figure 2.1‐3 – Ted’s Shed Exterior
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Figure 2.1‐4 – Ted’s Shed Interior
A 30,000 Btu/hr propane fired ventless Mr. Heater garage heater is used for space heating. 20
lb propane tanks are used for fuel storage. Figures 2.1‐5 – 2.1‐6 show pictures of the garage
heater and propane storage.
Figure 2.1‐5 – Ted’s Shed Propane Fired Ventless Heater
Biomass Prefeasibility Report Date: July 28, 2015 Great Lands Christian Church
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Figure 2.1‐6 – Ted’s Shed Propane Tank
Ted’s Shed is wired for future connection to the electric grid or to a diesel generator. Electricity
is not currently available at the camp.
An AkWarm report was completed to estimate the design heat load of Ted’s Shed since historic
fuel use is unavailable. The results estimate that the design heat load of the building is 27,000
Btu/hr. Anecdotal evidence suggests that this is reasonable since the 30,000 Btu/hr propane
heater is used for heating. The AkWarm report is provided in Appendix C.
2.2 CABINS
There are currently 4 cabins constructed for sleeping quarters. They are stick framed
construction with wood siding and a pitched steel roof. They are set up like a side by side
duplex with two separate entryways and a partition wall down the middle separating the
spaces. A shared attic loft spanning the entire cabin is available for additional occupancy and
can be accessed through pull down stairs. Figures 2.2‐1 – 2.2‐4 show pictures of the cabins, all
four cabins are identical.
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Figure 2.2‐1 – Cabin Exterior
Figure 2.2‐2 – Cabin Interior – Left Unit (Facing Front of Cabin)
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Figure 2.2‐3 – Cabin Interior – Shared Attic Loft
Figure 2.2‐4 – Cabin Exterior
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The cabins currently use two Mr. Heater Buddy ventless propane heaters rated at a maximum
output of 9,000 Btu/hr. A flexible plastic fuel line is run outside for connection to a 20 lb
propane tank. One heater is used in each side of the first floor partition. Annual fuel use is
unknown, however one 20 lb propane tank will run one heater on maximum output for 48
hours assuming the temperatures allow adequate vaporization of the propane in the tank to
feed the heater at its rated demand. Figure 2.2‐5 shows the heaters used in the cabins.
Figure 2.2‐5 – Cabin Propane Fired Ventless Heater
AkWarm reports were completed to estimate the design heat load of the cabins since historic
fuel use is unavailable. The results estimate that the design heat load of the cabin is 11,000
Btu/hr. Anecdotal evidence suggests that this is reasonable since two 9,000 Btu/hr propane
heaters satisfy the heating requirements of each cabin. The AkWarm report is provided in
Appendix C.
3.0 FOREST RESOURCE AND FUEL AVAILABILITY
The area surrounding The Gateway to the Arctic Camp is heavily forested. GLCC has an
agricultural permit that allows wood harvesting on the land. Significant acreage has been
cleared while constructing the camp, and cord wood has been stockpiled for seasoning for
future use. Additionally, Denali Log and Lumber is located 16 miles away from the camp, and
birch cordwood is available for purchase for $250/cord delivered to the site. GLCC requested
the evaluation of cord wood systems due to the abundant availability on their own land. Table
Biomass Prefeasibility Report Date: July 28, 2015 Great Lands Christian Church
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2 summarizes the available fuels for heating as well as their cost per 1 million Btu’s (mmBtu)
output comparison. Wood pellet costs are provided for comparison even though wood pellet
technologies are not evaluated in this report.
Table 3.0‐1 – Fuel Pricing and Cost of Energy for Heating
Fuel, Unit Appliance
Cost
per Fuel
Unit
Input Heating
Value, mmBtu
per Unit
Estimated
Appliance
Efficiency
Appliance
Output
Heating Value,
mmBtu/Unit
Appliance
Output
Heating Cost,
$/mmBtu
Cord Wood, Cord Catalytic Wood Stove $250.00 23.6 72.0% 16.99 $14.71
Wood Pellets, 40lb Bag Pellet Stove $5.88 0.304 78.0% 0.24 $24.80
#1 Fuel Oil, Gallon Vented Space Heater $4.00 0.134 87.0% 0.12 $34.31
Propane, Gallon Non‐Vented Space Heater $3.69 0.0913 99.9% 0.09 $40.46
Note:
1 ‐ Assumes 20% moisture content wet basis for cord wood and 23.6 mmBtu per 4’ x 4’ x 8’ cord of Birch.1
2 ‐ Input heating value assumes 8% moisture content wet basis for wood pellets with an average High Heating
Value of 8,255 Btu/lb of bone dry wood based on a mixture of Sitka Spruce (8,100 Btu/lb) and Western Hemlock
(8,410 Btu/lb)2.
4.0 PROPOSED BIOMASS SYSTEMS
Catalytic cord wood stoves were evaluated for the buildings at The Gateway to the Arctic Camp
since the camp is not currently connected to the electric grid, cord wood is the preferred fuel,
and the buildings are small and unoccupied for extended periods of time. A central cordwood
boiler system was initially considered but not pursued do to extended unoccupied periods at
the camp, potential for groundwater contamination with a pipe leak in a glycol system during
unoccupied periods, and electricity requirements for district pumping.
4.1 TED’S SHED HEATING SYSTEM
A catalytic cord wood stove sized at approximately 25,000 Btu/hr is recommended for heating
Ted’s Shed. The building is 1 story with an open layout that provides a good application for
wood stove heating. It is recommended that the stove is located centrally along the back
outside wall to provide even heating throughout the space. It is also possible to cook or boil
water on the top of these stoves, however this is not considered in this study.
Catalytic stoves reburn the smoke generated during combustion, are more efficient, and
generate less smoke when operated properly. Steps for operating a catalytic stove can vary
based on the manufacturer selected. However, typical operation requires bypassing the
catalytic element for the first wood charge on a cold start to warm up the stove and catalytic
element. Then for subsequent charges the damper is closed to reroute the gases through the
catalytic element, increasing efficiency and reducing smoke.
1 http://www.alaskawoodheating.com/energy_content.php
2 Avery, Robert B., Funck, James W., & Wilson, Pamela L. (2010). Fuelwood Characteristics of Northwestern Conifers
and Hardwoods (updated). Portland, Or.: U.S. Department of Agriculture, Forest Service, Pacific Northwest
Research Station.
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Installation would require a hearth pad to sit under the stove, a stack exiting through the roof
to allow flue gases to vent outdoors, flashing for the roof penetration, and a radiation shield for
the back wall. Electricity is not required to operate the stove. Fuel loading and ash removal are
manual. The existing propane heater and tank are small, portable, and can easily be used for
backup or during periods that wood is unavailable. Appendix A provides a plan view of the
proposed system.
4.2 CABIN BIOMASS HEATING SYSTEM
A catalytic cord wood stove sized at approximately 20,000 Btu/hr is recommended for heating
each cabin. A stove sized at 10,000 Btu/hr would be preferred, however 20,000 Btu/hr is
typically the smallest catalytic stove size that is available on the market. The cabins are
currently divided in half on the 1st floor using a partition wall. A large portion of the heat
provided from a wood stove is from heat radiation, therefore line of sight is helpful for effective
heating. Removal of all or a portion of the partition wall is recommended so that a single small
cord wood stove can be used to heat both sides of the cabin. Manually adjustable floor vents
can be installed in the attic floor to allow heat to rise into the attic loft when occupied.
Appendix A provides a plan view of the proposed system.
Installation would require a hearth pad to sit under the stove, a stack exiting through the roof
to allow flue gases to vent outdoors, flashing for the roof penetration, and a radiation shield for
the back wall. Electricity is not required to operate the stove. Fuel loading and ash removal are
manual.
Catalytic stoves are recommended, however the smallest catalytic stove may be too large for
the small cabins. If catalytic options cannot be found in this size, efficient EPA certified non‐
catalytic stoves would be the next best option. The existing propane heaters and tanks are
small, portable, and can easily be used for backup or during periods that wood is unavailable.
5.0 BENEFIT/COST ANALYSIS
Capital costs are estimated for the system based on recent quotations and bids provided by
cord wood catalytic stove manufacturers. These costs include the catalytic wood stoves, flue
pipes, hearth pads, flashing, radiation shields, and installation by GLCC staff. 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
5 catalytic wood stoves for 4 cabins
and Ted’s Shed installed by GLCC $25,025
It is assumed that GLCC staff and members would split wood for use in the wood stoves and
costs for wood splitting are not considered. Wood ash can be used as a soil amendment and a
direct replacement for lime. Wood ash from the stoves could be used on GLCC grounds to
Biomass Prefeasibility Report Date: July 28, 2015 Great Lands Christian Church
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potentially improve soil conditions. Wood stoves would not utilize electricity, therefore
electricity costs are not included for O&M costs. The catalytic elements will require
replacement every 5 to 7 years. The cost for replacement elements vary but typically average
$300 or less. An annualized cost of $50/year is included for replacement catalytic elements.
Table 5.0‐2 – Estimated Annual Operating Costs for 5 Catalytic Wood Stoves
Item Estimated
Annual Cost
Electricity $0
Ash Removal & Disposal $0
Catalytic Elements Annualized
Replacement Cost (5 Stoves) $250
Estimated Annualized O&M Cost $250
Notes:
1 – Assumes that GLCC land applies the ash from wood stoves as a soil
amendment on GLCC owned lands.
2 – Assumes that the replacement cost for a catalytic element is $300 and
replaced in all 5 units every six years by GLCC staff.
Potential annual savings are unknown since occupancy schedules will vary. However, one
4’x4’x8’ cord is equivalent to forty 20 lb propane tanks and would result in savings of $445 if
wood is purchased and $695 if GLCC wood resources are used at no cost. Table 5.0‐3 shows the
comparison of energy, cost, and savings per propane tank when using purchased birch
cordwood.
Table 5.0‐3 – Propane and Birch Cordwood Energy and Cost Comparison Summary
Propane Gallons
per 20 lb
Propane Tank
Output Energy per
Tank at 99.9%
Efficiency, mmBtu
Propane
Tanks
per Cord
Cost per
Propane
Tank
Cord Wood Cost
Equivalent of 1
Propane Tank
Savings
per
Tank
4.7 0.43 40.0 $17.34 $6.31 $11.04
Since annual fuel use is unknown, savings and paybacks cannot be determined for this project.
To provide an estimate of project potential, the quantity of propane tanks that would need to
be offset with cord wood are estimated to generate a range of simple payback periods on
project costs. Table 5.0‐4 provides potential simple payback periods in years, required annual
savings to generate the simple payback period, and the quantity of propane tanks that would
need to be offset with purchased cord wood and GLCC cord wood to generate the savings
required for the stated payback periods.
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Table 5.0‐4 – Propane Tank Offsets to Achieve Simple Payback Periods
Simple
Payback
Period, Years
Annual
Savings
Required
Qty of Propane Tanks
Offset Required to
Generate Payback
with Purchased Wood
Qty of Propane Tanks
Offset Required to
Generate Payback
with GLCC Wood
5 $5,005 454 289
10 $2,503 227 144
15 $1,668 151 96
20 $1,251 113 72
As a reference, AKWarm estimates of annual heat demand show that the 5 buildings would
require 364 propane tanks per year if they were occupied year round. Additionally, at the peak
demands, Ted’s Shed would need about one 20 lb propane tank each day, and each Cabin
would need one tank every two days.
Note that the output capacity of the heaters in the Cabins will be dictated by the tank’s ability
to vaporize the propane since they are stored outside. This ability is based on the level in the
tank and the temperature at which the tank is stored. Their output will drop below the 9,000
Btu/hr rating of the heaters when the outside temperature reaches about 0oF and continue to
drop off as the temperature drops.
Table 5.0‐5 lists the assumptions and values used to develop costs and savings in this study.
Table 5.0‐5 – Assumptions and Values Used in the Report
Item Value and Unit Source
Cord wood moisture content wet basis 20%WES E&E assumption
Propane high heating value 91,300 Btu/gal WES E&E assumption
Cord wood high heating value (Birch) 23.6 mmBtu/Cord University of Alaska Fairbanks
Cooperative Extension Service
Wood pellet high heating value 15.2 mmBtu/ton WES E&E assumption
Propane gallons per 20 lb tank 4.7 gallons WES E&E assumption
Propane unvented space heater efficiency (HHV)99%WES E&E assumption
Catalytic cord wood stove efficiency (HHV) 72%EPA minimum efficiency
Cord wood price $250.00/Cord Budget quote
Wood pellet price $6.00 per 40 lb bag Budget quote
Propane price $3.69/gallon GLCC
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6.0 CONCLUSIONS & RECOMMENDATIONS
This study concludes that Great Lands Christian Church can reduce annual operating costs for
space heating by installing high efficiency, low emission catalytic wood stoves. Benefits for
using high efficiency stoves for the camp are that they do not require electricity to operate,
there is no risk for leaks or freezing from leaving them unattended during unoccupied periods,
they will be able to utilize a fuel source that is readily available for harvest on GLCC lands, and
they can efficiently heat the spaces evaluated.
As GLCC 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 wood stoves in the cabins.
Wood stove capital costs based on detailed site investigations and direct quotes from
manufacturers.
Alternative funding sources (low interest loans, grants, and incentives).
Assessment of annual use for the buildings, and comparison of the savings based on this
usage to capital costs.
Consideration of the following regarding propane tank use:
o Outdoor propane tank connection exposes the tanks to ambient temperatures,
which will dictate the vaporization rate for the propane tanks. In extreme cold
temperatures when the most heat is needed from the tanks, the vaporization
rate drops off and this will be the limiting factor for the heat output. At ‐44oF,
the propane will remain in liquid form.
o When tanks are filled in cold conditions, and stored in cold conditions, they can
vent gas for pressure relief when brought inside and warmed. This should not be
a major issue, but should be considered when bringing the tanks into an
occupied space.
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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
are 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
are manual. A partial list of manufacturers include
England Stove Works, Sherwood Industries, Harman,
and Lopi.
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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 minimizes cycling
and allows the boiler to operate a more consistent rate
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 typically range from $7,000 to
$15,000 plus installation, but will vary based on size
needed an options selected. 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
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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, saw
dust and other biomass fuels. 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
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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. Specialty pre‐insulated steel systems
are also available when larger diameters, higher
pressures, or higher temperatures are needed.
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Appendix A
Conceptual Drawings
Teds Shed LayoutCatalytic Wood Stove6" Flue48'-0"22'-0"SCALE5'0'2.5' 5'Notes:1. This drawing is a conceptual layout for the purposes ofshowing one option for layout of a heating system. Finaldesign and layout will change based on equipmentselected, designer, and site conditions.Overhead DoorWESEE Great Lands Christian Church
Fairbanks, AK
Teds Shed
24'-0"16'-0"Loft AccessTyp.Existing Cabin LayoutNew Cabin LayoutPropane HeatersPropane TanksLoft AccessTyp.CatalyticWood Stove6" Flue24'-0"16'-0"SCALE5'0'2.5' 5'Notes:1. This drawing is a conceptual layout for the purposes ofshowing one option for layout of a heating system. Finaldesign and layout will change based on equipmentselected, designer, and site conditions.WESEE Great Lands Christian Church
Fairbanks, AK
Cabin 1-4
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Appendix B
Preliminary Capital Cost Estimates
Appendix B Great Lands Christian Church
Gateway to the Arctic
Line Item Value Units $/Unit Cost1&2
Catalytic wood stove rated at ~20,000 Btu/hr over 20 hours 5 $3,000 15,000$
40" x 40" Hearth Pad 5 $500 2,500$
Black pipe chimney 5 $750 3,750$
Flashing and rain cap 5 $200 1,000$
Radiation shield for back wall 5 $100 500$
Sub‐Total 22,750$
Contingency 10%2,275$
Total 25,025$
Notes:
4 ‐ Cost estimate is based on competitive bidding of equipment.
Catalytic Wood Stove Conceptual Capital Cost Estimate
1 ‐ The catalytic wood stove systems are assumed to be installed by GLCC members. Therefore, installation
costs are not included.
2 ‐ The stove size is approximate, is selected based on the smallest stoves currenly available on the market, and
will vary based on the manufacturer selected.
3 ‐ Assumes that professional services will not be required due to the simplicity of the installation.
WES Energy & Environment
Biomass Prefeasibility Report Date: July 28, 2015 Great Lands Christian Church
Final Gateway to the Artic
WES Energy & Environment
Appendix C
AkWarm Heating Load Estimates
Client:Nick Morrill
Home at:Ted's Shed
Talkeetna, AK 99676
Energy Flows below are in Btu/hour
Gross Gross Useable Gross Useable Natural
Month Hours Loss Internal Internal Solar Solar Infil cfm
Jan 744 18,490 3,855 3,855 185 183 27
Feb 678 16,689 3,855 3,855 451 447 26
Mar 744 15,219 3,855 3,855 867 864 24
Apr 720 11,136 3,855 3,855 1,122 1,115 21
May 744 7,624 3,855 3,849 1,075 1,055 18
Jun 720 4,724 3,855 3,421 1,105 935 16
Jul 744 3,731 3,855 3,025 1,048 671 13
Aug 744 4,616 3,855 3,386 837 750 14
Sep 720 7,234 3,855 3,835 620 615 17
Oct 744 11,587 3,855 3,855 426 423 21
Nov 720 15,699 3,855 3,855 248 246 25
Dec 744 18,400 3,855 3,855 111 110 26
Annual Energy Flows
Gross Loss: 98.5 MMBtu
Gross Internal: 33.8 MMBtu
Useable Internal: 32.5 MMBtu
Internal Utilization: 0.962
Gross Solar: 5.9 MMBtu
Useable Solar: 5.4 MMBtu
Solar Utilization: 0.915
Net Heat Load: 60.6 MMBtu
Design Heat Load
See the 'Design Heat Loss Report' for detailed information on heating system sizing.
Main Home: 26,747 Btu/hour
Garage: 0 Btu/hour
AkWarmCalc ver. 2.4.1.0, Energy Library ver. 3/30/2015
Client:Nick Morill
Home at:Cabin
Talkeetna, AK 99676
Energy Flows below are in Btu/hour
Gross Gross Useable Gross Useable Natural
Month Hours Loss Internal Internal Solar Solar Infil cfm
Jan 744 8,719 2,481 2,481 177 175 3
Feb 678 7,870 2,411 2,411 374 372 3
Mar 744 7,176 2,317 2,317 634 624 3
Apr 720 5,251 2,223 2,223 754 718 2
May 744 3,595 2,154 2,107 669 595 2
Jun 720 2,228 2,129 1,747 657 397 2
Jul 744 1,759 2,154 1,515 634 242 1
Aug 744 2,177 2,223 1,757 540 338 1
Sep 720 3,411 2,317 2,199 450 436 2
Oct 744 5,464 2,411 2,411 337 335 2
Nov 720 7,403 2,481 2,481 226 225 3
Dec 744 8,677 2,506 2,506 111 110 3
Annual Energy Flows
Gross Loss: 46.5 MMBtu
Gross Internal: 20.3 MMBtu
Useable Internal: 19.1 MMBtu
Internal Utilization: 0.940
Gross Solar: 4.1 MMBtu
Useable Solar: 3.3 MMBtu
Solar Utilization: 0.820
Net Heat Load: 24.0 MMBtu
Design Heat Load
See the 'Design Heat Loss Report' for detailed information on heating system sizing.
Main Home: 11,003 Btu/hour
Garage: 0 Btu/hour
AkWarmCalc ver. 2.4.1.0, Energy Library ver. 3/30/2015