HomeMy WebLinkAboutSitka Centennial Hall & Library Renewable Energy Feasibility Analysis - Jul 2012 - REF Grant 7040071Renewable Energy Feasibility Analysis
Harrigan Centennial Hall
Kettleson Memorial Library
City and Borough of Sitka
Prepared by:
Final Report
July, 2012
Alaska Energy Engineering LLC
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Centennial Hall and Library 1 Renewable Energy Feasibility Analysis
Table of Contents
Section 1:Executive Summary 3
Introduction ........................................................................................ 3
Heat Pump Technology ...................................................................... 3
Life Cycle Cost Analysis .................................................................... 4
Section 2:Introduction 7
Introduction ........................................................................................ 7
Heat Pump Benefits ............................................................................ 8
Heat Pump Options ............................................................................ 9
Section 3:Life Cycle Cost Methodology 15
Economic Factors ............................................................................. 15
Construction Costs ........................................................................... 15
Operating Costs ................................................................................ 16
Energy Costs .................................................................................... 17
Section 4:Harrigan Centennial Hall 19
Introduction ...................................................................................... 19
Heating System Options ................................................................... 19
Life Cycle Cost Analysis .................................................................. 21
Section 5:Existing Kettleson Memorial Library 27
Introduction ...................................................................................... 27
Heating System Options ................................................................... 28
Life Cycle Cost Analysis .................................................................. 29
Section 6:Renovated Kettleson Memorial Library 35
Introduction ...................................................................................... 35
Heating System Options ................................................................... 35
Life Cycle Cost Analysis .................................................................. 36
Appendix A:Centennial Hall Schematic Diagrams
Appendix B:Centennial Hall Sizing and Life Cycle Cost Calculations
Appendix C:Library Conceptual Diagrams
Appendix D:Library Sizing and Life Cycle Cost Calculations
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Section 1
Executive Summary
INTRODUCTION
This report presents the findings of a Renewable Energy Feasibility Analysis for Harrigan Centennial
Hall and Kettleson Memorial Library in Sitka, Alaska. The intent of this analysis is to determine if
there is economic incentive to invest in heat pump technologies to heat and cool the buildings.
Centennial Hall will undergo a major renovation and expansion. This feasibility analysis evaluates
whether the building should be converted to renewable energy heat pumps as part of the renovation
project. The Library may also undergo a major renovation and expansion. The feasibility analysis
evaluates options for integrating heat pumps into the existing building and into a renovated building
that includes a 60% expansion.
HEAT PUMP TECHNOLOGY
Heat pumps are desirable systems for buildings in Sitka. The technology is mature and has been
adapted to heating dominated operating modes and cold climates. Benefits include:
High conversion efficiency
Extracts heat from the environment, significantly reducing the amount of purchased energy and
the cost of long-term energy inflation
Powered by renewable hydroelectric power
Reduction in greenhouse gas emissions
This study evaluates the following heat pump technologies for the buildings:
Ground Source Heat Pumps: This system utilizes a loopfield to extract heat from the ground and
transfer it to the building. The technology is mature and there are successful commercial
installations in Juneau. The thermal conductivity of the ground, which is essential in sizing the
systems, is not known. An assumption was used for the analysis.
Seawater Heat Pumps: This system transfers heat from seawater via an intake structure or
groundwater wells located near the shoreline. Successful commercial seawater heat pump systems
are in use in Juneau and Seward. Permits will be required for the installation of intake and
discharge structures and for discharging the seawater.
Air Source Heat Pumps: This system utilizes outdoor coils to transfer heat from/to the air.
Commercial installations using newer variable refrigerant flow technology have been recently
installed in coastal Alaska. There is no long-term data on the efficiency and durability of the
equipment, but the technology appears to provide significant energy savings over traditional
systems.
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The availability of hydroelectric power is central to the economics of a heat pump system. Sitka is
experiencing load growth due to electric heating, which has resulted in diesel supplementation of the
hydroelectric generation. It is likely that diesel supplementation will occur during the life of a heat
pump system. The analysis takes this into account by using a proposed 9% per year rate increase for
the first two years and 2.5% electric inflation in the remaining years. This rate of electric inflation
greatly exceeds historic inflation which has been around 1% per year.
LIFE CYCLE COST ANALYSIS
Harrigan Centennial Hall
The proposed renovation and expansion of Centennial Hall provides an excellent opportunity to
convert the building to heat pump technologies. The analysis compares the life cycle cost of the
baseline HVAC system (fuel oil boilers, air-cooled condensers, variable volume air handling system)
with potential heat pump arrangements.
Life Cycle Cost Comparison – Centennial Hall
Heating System Construction Maintenance Energy Total LCC
Baseline HVAC System $1,970,000 $250,000 $1,790,000 $4,010,000
Ground Source Heat Pump System $3,060,000 $120,000 $690,000 $3,870,000
Groundwater Well Heat Pump System $2,850,000 $250,000 $400,000 $3,500,000
Seawater Intake Heat Pump System $3,650,000 $260,000 $400,000 $4,310,000
Air-source Heat Pump System $2,110,000 $840,000 $400,000 $3,350,000
The economic comparison of the systems shows that the heat pump options require a significant
investment that factors greatly into overall life cycle cost.
The air source heat pump system and the seawater well heat pump system have essentially equal life
cycle costs under all scenarios. They have a life cycle cost of $3,425K +/- 2% which is very close
when estimating and forecasting costs over 30 years. The air source heat pump system requires a
lower investment while the seawater system has lower maintenance and energy costs. The seawater
system can be expanded to include the library but it also requires a permitting process and ongoing
permitting requirements.
Existing Kettleson Memorial Library
The opportunities for converting an existing building to heat pumps are limited by the cost of
integrating with the existing heating and ventilating systems. In the case of the Library, the best heat
pump option is to convert the existing hydronic fuel oil boiler heating system to a lower temperature
system and integrate ground source, seawater source, or air source heat pumps into the system.
A life cycle cost comparison shows that retaining the existing systems has the lowest life cycle cost.
This finding is representative of the challenges of retrofitting heat pumps into an existing building.
The Library is a relatively small building with modest energy requirements. A heat pump system does
not generate sufficient energy savings to offset the high cost of retrofit. Of the heat pump systems, the
seawater source system has the lowest life cycle cost, primarily because it is assumed to share
seawater infrastructure with Centennial Hall.
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Life Cycle Cost Comparison – Existing Library
Heating System Construction Maintenance Energy Total LCC
Baseline Fuel Oil Boilers $0 $110,000 $570,000 $680,000
Ground Source Heat Pump System $490,000 $110,000 $220,000 $810,000
Seawater Heat Pump System $470,000 $160,000 $140,000 $760,000
Air Source Heat Pump System $390,000 $230,000 $160,000 $780,000
Renovated Kettleson Memorial Library
A project to renovate and expand the Library has been proposed. An analysis was performed to
determine whether it is feasible during a 60% expansion project to convert the Library from fuel oil
boiler heat to renewable heat pumps.
The analysis compares the life cycle cost of the baseline HVAC system (fuel oil boilers, air-cooled
condensing units, variable volume air handing units) with potential heat pump arrangements. A life
cycle cost comparison shows that the seawater heat pump system has the lowest life cycle cost. This
result occurs because it is assumed the cost of the seawater infrastructure is shared with the
Centennial Hall system. The ground source heat pump systems and air source heat pump systems also
offer a lower life cycle cost than the baseline system.
Life Cycle Cost Comparison – Renovated Kettleson Library
Heating System Construction Maintenance Energy Total LCC
Baseline Fuel Oil Boilers $390,000 $140,000 $800,000 $1,330,000
Ground Source Heat Pump System $620,000 $150,000 $190,000 $960,000
Seawater Heat Pump System $490,000 $190,000 $180,000 $860,000
Air Source Heat Pump System $560,000 $300,000 $180,000 $1,040,000
Summary
For investment in a heat pump system to be preferred over the relatively lower construction cost of
the traditional baseline systems—likely siphoning dollars from other priorities—the system should
overwhelmingly have a lower life cycle cost. This is the case for the Centennial Hall Renovation and
Expansion where either the seawater source or air source heat pump systems offer a life cycle savings
over the traditional system. For the proposed Library renovation and expansion, the seawater system
also has the lowest life cycle cost, provided that the building is served by a seawater system that also
serves Centennial Hall.
The favorable economics of converting the buildings to heat pump technology can be directly
attributed to the proposed renovation projects. The proposed upgrade of the heating, ventilating, and
air-conditioning systems reduces the cost of converting the building to heat pump technologies. An
interesting opportunity would be to install a seawater system that could be expanded to supply other
buildings in the downtown region.
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Section 2
Introduction
INTRODUCTION
This report presents the findings of a Renewable Energy Feasibility Analysis for Harrigan Centennial
Hall and Kettleson Memorial Library in Sitka, Alaska. The intent of this analysis is to determine if
there is economic incentive to invest in heat pump technologies to heat and cool the buildings.
The analysis is performed by Jim Rehfeldt, P.E. of Alaska Energy Engineering LLC with technical
assistance by the following subconsultants:
Steve Theno, Principal Mechanical Engineer, PDC Inc. Engineers
Danny Rauchenstein, Senior Mechanical Engineer, PDC Inc. Engineers
Chris Gianotti, Senior Engineer, PND Engineers, Inc.
The purpose of this analysis is to compare the life cycle cost of retaining the existing HVAC schemes
or converting the buildings to heat pump heating and cooling. The options are evaluated using life
cycle cost analysis, which compares construction, maintenance, and energy costs of the heating
options over a 30-year period.
The findings are highly sensitive to the economic factors and energy costs used for the analysis.
Future energy inflation can significantly affect the findings, yet there is no one authority for these
values. For this reason, a sensitivity analysis will be used where base case, low case, and high case
values for electricity and fuel oil inflation are evaluated.
Harrigan Centennial Hall
The building will undergo a major renovation and expansion. The scope includes replacement of the
ventilation and air-conditioning systems. This feasibility analysis evaluates whether the building
should be converted to renewable energy heat pumps as part of the renovation project.
Existing HVAC Systems
Centennial Hall is currently heated by two fuel oil boilers and cooled by an air-cooled chiller. The
auditorium has unit ventilators that provide ventilation and air-heating. The system is capable of
natural cooling when outside temperatures are below 60°F. The chiller provides mechanical cooling
during periods of warmer weather.
The meeting rooms, offices, museum, and support spaces have fan coil units that condition the spaces
as needed. The units circulate and condition room air, supplying heat from the boilers and providing
cooling from the chiller as needed. Unit ventilators supply ventilation air to the ceiling space which is
then drawn into each fan coil. This system does not provide sufficient natural cooling, so the chiller
operates year-round to cool interior rooms with high internal heat gains.
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Proposed HVAC Systems
The analysis uses the following baseline for evaluating whether there is incentive to invest in heat
pump technologies.
Heating: Fuel oil boilers
Cooling: Air-cooled direct expansion cooling system
Ventilation: Conventional variable air volume ventilation system.
The proposed scheme will naturally cool the building except when outside temperatures exceed 60°F.
As such, it will significantly reduce mechanical cooling energy consumption.
Kettleson Memorial Library
Existing Building
The Library is currently heated by a fuel oil boiler and ventilated with constant volume air handling
units. There is no mechanical cooling. The feasibility analysis looks at options for integrating heat
pumps into the existing system.
Proposed Renovation and Expansion
A proposed renovation and expansion project is looking at several options that will renovate the
building and increase the size of the library by 30%, 60% or 100%. The feasibility analysis is based
on a 60% increase in building size and evaluates whether the building should be converted to
renewable energy heat pumps as part of the renovation project. The existing constant volume
ventilation systems are not likely to be adaptable to the new floor plan. It is assumed that the systems
will be replaced in the renovation with the following baseline HVAC scheme:
Heating: Fuel oil boilers
Cooling: Natural cooling
Ventilation: Conventional variable air volume ventilation systems
HEAT PUMP BENEFITS
Community Benefits
Heat pumps are desirable systems for residential and commercial buildings in Sitka. The technology
is mature and has been adapted to heating dominated operating modes and cold climates. Some of the
primary benefits include:
High conversion efficiency
Extracts heat from the environment, significantly reducing the amount of purchased energy and
the cost of long-term energy inflation
Powered by renewable hydroelectric power
Reduction in greenhouse gas emissions
Heat pump heating efficiency typically ranges from 220-360%, depending upon the type of heat
pump and the temperature of the heat source. A 300% efficient heat pump will consume one unit of
energy to extract two units of heat from the environment and supply three units to the building. In
comparison, fuel oil and electric boiler plants have nominal seasonal efficiencies of 70% and 95%,
respectively.
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Heat pumps are powered by electricity, which is predominately hydroelectric generated in Sitka. As
such, they reduce greenhouse gas emissions when compared to fuel oil heated buildings. The same
can be said for electric resistance heat, but there is an essential difference between the two. Heat
pumps make efficient use of available hydroelectric resources, which meshes well with community
sustainability goals to make efficient use of renewable energy. Electric resistance heat has a much
lower efficiency, which has led to high load growth and depletion of the hydroelectric supply.
Cost of Heat Comparison
The following chart provides a 30-year heating cost comparison for fuel oil and electric heating
options. The widening gap between the cost of fuel oil heat and the other sources is the primary driver
for conversion to renewable energy sources. The conversion efficiency of heat pumps offers the
greatest protection from future energy inflation.
By transferring heat from the environment to the building, a heat pump requires less purchased
energy to meet the load, and most importantly, significantly reduces the long-term effect of energy
inflation.
HEAT PUMP OPTIONS
Potential heat pump technologies for heating and cooling the buildings include air-source, which
extract heat from outside air, and water-source, which extract heat from the ground or an adjacent
body of water such as the ocean. Both air-source and water-source heat pumps can produce hydronic
heating water (water-side) or supply heat via ventilation air (air-side). They can also provide cooling,
which is typically a small portion of overall energy consumption.
Retrofitting heat pumps into existing buildings is challenging and subject to limitations. For air-side
heating, the existing ventilation systems must have space for a heat pump coil and must also have
sufficient fan and motor capacity to maintain air flow with the added coil pressure drop.
$0.00
$50.00
$100.00
$150.00
$200.00
$250.00
2013 2015 2017 2019 2021 2023 2025 2027 2029 2031 2033 2035 2037 2039 2041$ / MMBtu
Year
Cost of Heat Comparison
Fuel Oil Boiler Heat @ 6.6%
Electric Boiler Heat @ 9% (Years 1 2) and 2.5% (Years 3 30)
Air Source Heat Pump @ 9% (Years 1 2) and 2.5% (Years 3 30)
Ground Source Heat Pump @ 9% (Years 1 2) and 2.5% (Years 3 30)
Seawater Source Heat Pump @ 9% (Years 1 2) and 2.5% (Years 3 30)
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For existing water-side systems that operate on 180°F boiler water, a heat pump that supplies a
maximum of 120°F heating water will reduce the maximum heat output of the existing heating units.
The exception is radiant floors which heat with 90-120°F water. If a heat pump system is retrofitted
into the building, the heating units must be increased in size or additional heating units must be
installed.
Ground Source Heat Pumps
Ground source heat pumps utilize a loopfield to extract heat from the ground and transfer it to the
building. For these buildings, the loopfield consists of vertical pipe loops installed in 300’ deep bore
holes that are backfilled with a thermally conductive grout. The pipe loops are connected to
horizontal piping that manifolds the boreholes together and runs to the building room. The loopfield
is installed completely underground and does not impact surface features of the site.
An antifreeze solution flows through the loopfield piping. During heating mode, the relatively warmer
ground transfers heat to the fluid, where it is extracted by the heat pump. The heat pump utilizes a
compressor/condenser cycle to “lift” the ground source heat to 120°F heating water for the building.
In cooling mode, the process works in reverse.
Ground thermal conductivity is an important parameter in sizing a loopfield. A thermal conductivity
test is required to determine how conductive the ground is and the rate of recharge. A thermal
conductivity test is not available for the project site, so the analysis is based on a sizing factor of 250
lineal feet of borehole per ton (12,000 Btu per hour) of heating. If a ground source heat pump system
is preferred, a thermal conductivity test is required to confirm this assumption.
Horizontal loopfields are also an option for the ground source heat pump system. They use horizontal
pipe loops installed over 6’ below ground. Horizontal loopfields require significantly more surface
area and are limited in their ability to recharge. As such, they are mostly limited to residential and
small commercial installations with smaller heating demands. As such, a horizontal loopfield is not
applicable to these buildings.
The parking area around the Centennial Building and the Library will be renovated; some of the work
will be started this summer. The loopfield is installed completely underground and does not impact
the surface features of the site. For cost estimating purposes, it is assumed that the loopfield will be
installed as part of the parking lot renovation project that is currently in design.
Seawater Heat Pumps
The seawater is a viable heating and cooling source for the buildings. It is warmer than the ground
during the winter—which improves heat pump efficiency—and is sufficiently cool to provide cooling
for a few warm days each year.
The seawater can be extracted from the sea via an intake structure or drawn from groundwater wells
located near the shoreline. A well would eliminate intake structures and if the seawater is filtered by
the ground, reduce organic growth in the seawater piping. Unfortunately, there is no history of
groundwater wells in the vicinity of Centennial Hall. However, recent excavations on the site
reportedly infiltrated with seawater, suggesting that there is potential to extract seawater from a well.
Due to the corrosive nature of seawater, it must be isolated from the heat pump by a titanium heat
exchanger. The heat exchanger also provides a second wall of protection between the heat pump
refrigerant and the environment. After heat is transferred from the seawater, it will be discharged into
the ocean.
Seawater intakes, piping, and equipment will collect and provide a breeding ground for organic
matter. They must be designed to be regularly cleaned to ensure system viability and efficiency.
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Groundwater (Seawater) Well
One option for a cost effective intake facility is a groundwater well with a turbine pump. This option
utilized a perforated pipe driven into the ground. For the purpose of analysis, it is assumed that a
seawater well will supply sufficient quantities of seawater at a minimum temperature of 38°F and
suitable quality for a heat pump system.
The pump is located in a well house that is easily accessible and whose floor is above the high tide
line or approximately 15 feet. The well house should be of adequate size for the pump and all
associated maintenance tasks.
This alternative is only feasible if there is adequate flow of seawater through the soils and into the
pipe casing. A well test is required to determine the available flow. No in-water permits are
necessary for this intake alternative as there is no in-water work.
Maintenance Requirements: The seawater pumps and piping will require regular cleaning to remove
growth and organic accumulation. The system will be designed with pig ports so a pig can be injected
into the pipeline to clean it.
Environmental and Permitting Requirements: This alternative will require permits for performing
work in the water and for discharge to the ocean. Such permits are likely obtainable as the impacts to
the aquatic environment are not believed to be significant and the intake/discharge area is a
previously impacted area. Engineered drawings and descriptions will be required to permit the
seawater intake/discharge. The following certificates and permits are potentially required, dependent
upon agency review for applicability to the regulations:
Water Right Certificate: There is no requirement for a water right to extract seawater.
Alaska Pollution Discharge Elimination System Permit, Alaska Department of Environmental
Conservation: Covers water quality of discharge and temperature change issues. A mixing zone
may be required if the temperature of the discharge is more than 5°F warmer than the ocean.
Habitat Protection: Alaska Department of Fish and Game permits, U.S. Fish and Wildlife permit
Navigation Permit: U.S. Coast Guard navigation approval.
Seawater Intake
If the groundwater (seawater) well does not have adequate flow, a wet well system could be
constructed. This alternative would consist of a concrete wet well of adequate size be constructed to a
depth of -15 feet MLLW. A pipeline would run from the wet well to an intake structure off the
shoreline. This line would have a screened intake at approximately -10 feet MLLW. The intake would
be in an area where anchors, vessel traffic at extreme low tides or other activities that would damage
the intakes would not occur.
The pipelines would be of high density polyethylene and concrete anchor collars would ballast the
line below the tideline. The line would be routed up the harbor shore above the mudline to an
elevation where the pipes could be trenched into the ground, approximately +5 feet MLLW. At that
point the lines would travel horizontally to the wet well.
The pump will be located in a pump house of adequate size to perform maintenance.
Maintenance Requirements: The seawater piping will require regular cleaning to remove growth and
organic accumulation. The system will be designed with pig ports so a pig can be injected into the
pipeline to clean it. A diver will be needed to clean the intake structure and remove the pigs. The
turbine pumps will require regular maintenance.
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Environmental and Permitting Requirements: This alternative will require permits for performing
work in the water and for discharge to the ocean. Such permits are likely obtainable as the impacts to
the aquatic environment are not believed to be significant and the intake/discharge area is a
previously impacted area. The following certificates and permits are required:
Water Right Certificate: There is no requirement for a water right to extract seawater.
Work in the Ocean: Corps of Engineer permit
Alaska Pollution Discharge Elimination System Permit, Alaska Department of Environmental
Conservation: Covers water quality of discharge and temperature change issues. A mixing zone
may be required if the temperature of the discharge is more than 5°F warmer than the ocean.
Habitat Protection: Alaska Department of Fish and Game permits, U.S. Fish and Wildlife permit
Navigation Permit: U.S. Coast Guard navigation approval.
Seawater Drywell
A dry well system with centrifugal pumps near the low tide elevation was considered but was not
believed to be feasible due to confined space regulations of such a system. Anticipated maintenance
for a pump in a saltwater environment will be significant. The cost of entering and working in a
confined space will be significant.
Seawater Discharge
The outlet for a seawater heat exchange system will be to an ocean outfall. The outlet would be
similar to the screened intakes of the wet well intake alternative. The outlet location will need to be a
sufficient distance from the intake to avoid potential thermal short-circuiting.
Maintenance Requirements: The discharge piping will require regular cleaning to remove growth and
organic accumulation. The system will be designed with pig ports so a pig can be injected into the
pipeline to clean it. A diver will be needed to clean the discharge structure and remove the pigs.
Air Source Heat Pumps
Air source heat pumps transfer heat from/to the ambient air to heat or cool the building. Technology
improvements have made them effective at heating in cold climates and capable of varying their
output with the heating or cooling load.
For the existing library, an air-to-water heat pump that produces hydronic heating water is most
readily integrated into the existing systems.
The optimal configuration for the renovated building options utilizes outdoor heat pump units that
transfer heat with interior fan coil units that circulate and condition air within each thermal zone. The
heat pump adds or extracts heat as needed to condition the space. The proposed arrangement is a
variable refrigerant flow (VRF) system, which utilizes refrigerant piping between the outdoor HP and
indoor fan coils to move heat around the building. Ventilation air is supplied by energy recovery
ventilators that recover heat from exhaust and relief air to preheat the ventilation air that is supplied to
each fan coil unit.
Cold climate VRF heat pumps are not in wide use and there is no historic operating data to assess
their real-time performance in Sitka’s temperate marine environment. They were recently installed in
Blatchley Middle School, which offers the opportunity to gain valuable short-term performance data
for Sitka’s maritime climate. It is prudent to understand the following concerns when considering air-
source heat pump technologies:
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The outdoor unit extracts heat by cooling outside air. This can cause moisture in the air to
condense and freeze on the coil surface. When the frost builds up and restricts air flow, the unit
initiates a defrost cycle that sends heat to the outdoor coil to melt any frost accumulation.
Optimization of defrost operation is essential to maximize equipment efficiency while operating
in our unique maritime climate. While air-source heat pumps are successfully heating buildings in
coastal Alaska, there is incentive to reduce defrosting operation through control strategy
optimization.
The technology has evolved so that air source heat pumps can efficiently heat, even during cold
weather, but there is no long-term data on the maintenance requirements imposed by our climate
or the actual service life of outdoor units that are harshly exposed to maritime salt-laden air.
The capability to maintain heat pump systems, both in-house and through local refrigeration
contractors, must be developed. This is true of all heat pumps, but more important for air source
heat pumps that are outdoors and more affected by climate. As the use of these systems
increases—a likely occurrence if current installations are successful—the capability to maintain
them will be developed within our communities.
The heat pump is located outdoors where it is exposed to salt-laden air, rain, and blowing snow,
which can reduce its performance. The optimum location is within a louvered room which protects
the equipment from the elements and mitigates noise. A successful arrangement is for the heat pump
to draw air in through louvers and then discharged through an exhaust duct to the outdoors.
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Section 3
Life Cycle Cost Methodology
The purpose of the feasibility analysis is to compare the life cycle cost of renewable energy heating
systems for the buildings. The findings are highly sensitive to the economic factors, energy costs, and
energy inflation used for the analysis. While future energy inflation often has the greatest impact,
there is no authority for these values. For this reason, a sensitivity analysis is used where base case,
low, and high values for electricity and fuel oil inflation are evaluated.
ECONOMIC FACTORS
The following economic factors are used in the analysis:
Economic Period: The economic period is set at 30 years with all costs based on 2013
construction.
Nominal Interest Rate: This is the nominal rate of return on an investment, without regard to
inflation. The CBS estimates that the bond rate will be between 4 and 7%. The analysis uses a
rate of return of 5.5%.
Inflation Rate: The Consumer Price Index has risen at a rate of 2.9% over the past 20-years. The
State of Alaska predicts general inflation of 2.5-3% per year. The analysis is based on a 2.9% rate
of inflation over the 30-year economic period.
CONSTRUCTION COSTS
Ground Source Heat Pump System: Optimal sizing of the loopfield requires an energy model to
predict hourly cooling and heating loads, a test borehole, and a thermal conductivity test. To
determine the feasibility of a ground source heat pump system, the following assumptions were made,
based on recent loopfield designs in Juneau:
Loopfield sizing of 250 tons per lineal foot of borehole.
The loopfield cost is based on mobilizing a drilling company from the Juneau. The loopfield for
the Juneau Airport and Dimond Park Aquatic Center cost $22 per lineal foot of borehole. The
cost of the loopfield is estimated at $36 per lineal foot to account for the smaller size of this
loopfield, likely rock subsurface, and inflation.
Groundwater Well Heat Pump System: It is assumed that a well near the building will produce
seawater of sufficient quality and capacity to supply a heat pump system. A test well is required to
validate this assumption. It is assumed that the discharge permit will be granted.
Seawater Intake Heat Pump System: It is assumed that an intake in the adjacent harbor will produce
seawater of sufficient quality and capacity to supply a heat pump system. It is assumed that permits
for construction and discharge will be granted.
Air Source Heat Pump System: It is assumed that a louvered space will be provided.
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OPERATING COSTS
Operating costs include maintenance and repair cost—on an annual and intermittent basis—and
equipment replacement costs at the end of its expected service life. The costs are derived from
industry standards for the long-term operation of the systems.
Maintenance and Repair
The heating systems will have the following maintenance and repair requirements. Heat pumps have
higher maintenance requirements than the existing systems. It is assumed that maintenance will be
performed by CBS facilities staff except where noted.
Fuel Oil Boilers: Requires daily inspections, monthly service, and annual cleaning of the firebox
and a combustion test.
Ground Source Heat Pump: Requires daily inspections, monthly service, 3-month service, and
annual cleaning of the heat transfer surfaces. In addition, a factory tune up is required every five
years. It is assumed that the 3-month service, annual maintenance and factory tune-ups will be
contracted out.
Air Source Heat Pump: Requires daily inspections, monthly service, monthly cleaning of the
outdoor unit, and annual cleaning of the heat transfer surfaces. In addition, a factory tune up is
required every five years. It is assumed that the monthly/annual maintenance and the factory
tune-ups will be contracted out.
Pumps: Require annual lubrication and periodic replacement.
Seawater Intake/Discharge: A diver will need to clean the intake/discharge structures and the
seawater piping will require pigging every two years.
Seawater Heat Exchanger: Requires annual cleaning.
Air Handling Units and Energy Recovery Ventilators: Require daily inspection, monthly service
and filter replacements every three months.
Replacement
The following heating and cooling equipment will require replacement at the end of its expected
service life:
Ground Source Heat Pump: Expected service life of 18 years.
Air Source Heat Pump: Expected service life of 12 years.
Energy Recovery Ventilator: Expected service life of 20 years.
Fan Coil Unit: Expected service life of 20 years.
Salvage
Most of the equipment will have reached the end of its service life at the end of the analysis period.
The exception is the GSHP loopfield which has a 75-year service life and will have 45 remaining
service years. Its salvage value is included in the analysis.
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ENERGY COSTS
Fuel Oil
Current Cost
The CBS currently pays $3.76 per gallon for #2 heating oil.
Future Inflation
Base Fuel Oil Case: In recent years, fuel oil inflation has been very sporadic, with a decidedly
upward trend in prices. Looking at oil prices over a longer period will smooth out the data and
provides a longer-term assessment of future costs. Using this perspective over the past 25-years, fuel
oil inflation has averaged 6.6% per year. The base case assumes that future fuel inflation will
continue at this rate.
High Fuel Oil Case: There is potential for world oil demand to increase due to increased
consumption by developing countries and/or an expanding global economy. Disruption of the world
oil supplies could also affect supply, causing prices to rise. The high case assumes these factors and
others could cause fuel inflation to be higher than the base case at 8% per year.
Low Fuel Oil Case: The U.S. Energy Information Agency predicts fuel oil inflation of 4.8% per year
for the next 25-years. While this reference has historically under-predicted actual fuel oil inflation, it
is possible that future fuel oil inflation may be lower than the base case due to: new technologies that
increase oil field production; new sources such as oil sands; and efficiency gains that reduce global
oil demand. These factors and others could lead to less demand which would result in fuel oil
inflation lower than the base case at 4.8% per year.
Electricity
Current Cost
Electricity is supplied by the CBS Electric Department. Power generation facilities include Blue Lake
Hydro, Green Lake Hydro, and the Jarvis Street diesel plant.
The building is billed under the General Services Rate, which charges for both electrical consumption
(kWh) and peak electric demand (kW). Electrical consumption is the amount of energy consumed and
electric demand is the rate of consumption. Electric demand is determined by averaging demand over
a continuously sliding fifteen-minute window. The highest fifteen-minute average during the billing
period determines the peak demand. The following table lists the current electric charges:
General Services Rate
Monthly Charge Rate
Energy Charge per kWh
First 500 kWh 14.17¢
Over 500 kWh 9.03¢
Demand Charge per kW $4.50
Future Inflation
Over recent history, Sitka’s electricity inflation has been low, lagging general inflation. However,
electric heating conversions have created load growth that has caused the utility to use more diesel
supplementation to meet the load. Diesel supplementation last winter resulted in a 1.35¢ per kWh fuel
surcharge.
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To reduce diesel supplementation, the dam at Blue Lake will be raised, increasing hydroelectric
power production by 27%. The utility recently completed a rate design study that recommended
raising rates 9% per year for the next two years. This increase is included in the analysis.
Base Electric Case: Even with the Blue Lake expansion and proposed rate increase, electric heating
loads are likely to continue to place demands on the hydroelectric generation facilities. Energy
balance reports for Southeast Alaska communities show that heating loads are 175% greater than the
non-heating load. While most of the heating load is currently met with fuel oil, only a small
percentage of this large potential load needs to convert to electricity to place demands on the electric
grid. In essence, future electricity prices may be tied to fuel oil inflation. The life cycle cost analysis
uses an electric inflation of 2.5% to account for the impacts of future fuel oil to electric heat
conversions.
High Electric Case: If fuel oil prices continue to rise, load growth due to electric heating loads will
increase. This scenario will result in greater diesel supplementation in the short-term and possible
construction of additional hydroelectric generation as a long-term measure. Higher electric rates will
result. The high case assumes these factors will result in an average electric inflation rate of 4%.
Low Electric Case: The low case assumes that load growth does not deplete the hydroelectric
surplus; electric rates continue at the historic inflation rate of 1%.
Summary
The following table summarizes the energy and economic factors used in the analysis. A sensitivity
analysis is also provided to determine how modest variations in energy inflation affect the results.
The following table shows the base, high and low case energy inflation that is applied to the analysis.
Summary of Economic and Energy Factors
Factor Rate or Cost
Nominal Discount Rate 5.5%
General Inflation Rate 2.9%
Electricity, 2013 10.9¢ per kWh
Electricity Inflation 1 1%, 2.5% (base), 4%
Fuel Oil $3.76 / gallon
Fuel Oil Inflation 1 4.8%, 6.6% (Base), 8%
1. The inflation rates for electricity and fuel oil represent the base case and
the low and high cases used for the sensitivity analysis.
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Section 4
Harrigan Centennial Hall
INTRODUCTION
The proposed renovation and expansion of Centennial Hall provides an excellent opportunity to
convert the building to heat pump technologies. Incorporating heat pumps will require added
investment in the heat pumps and the well field of seawater intake, but the ventilation and cooling
systems can be readily designed for heat pump technologies with minimal added cost of construction.
HEATING SYSTEM OPTIONS
Traditional HVAC System
Centennial Hall is currently heated by two fuel oil boilers and cooled by an air-cooled chiller. The
building will undergo a major renovation and expansion that will include a complete replacement of
the ventilation and air-conditioning systems. A preliminary calculation determined that the existing
boilers have sufficient capacity for the expanded building.
The design team has not identified a proposed HVAC scheme for the renovated building. A
traditional system that retains the fuel oil boiler hydronic heating system and replaces the ventilation
systems with traditional variable air volume reheat systems is used as the baseline for this analysis.
Further optimization of the HVAC systems is likely to occur in the design phase of the project.
The baseline HVAC system consists of:
Heating: Existing fuel oil boilers
Cooling: Natural cooling with outside air supplemented with air-cooled compressor units on
warm days.
Ventilation: Separate variable air volume ventilation systems for the auditorium, meeting and
office rooms, and the museum.
Ground Source Heat Pump System
Heating
The proposed arrangement adds a ground source heat pump system to the baseline system to heat the
building, retaining the existing fuel oil boilers to supplement when needed. The heat pump is sized for
50% and the boilers for 100% of the design heating load. An energy analysis determined that a heat
pump sized for 50% of the design load will supply 80% of the heating requirement. Since a GSHP
system has high capital costs, this sizing will reduce the ground couple investment while optimizing
the amount of extracted heat.
The ground source heat pump will utilize a vertical loopfield located under the parking area.
Preliminary sizing is: 32 boreholes, 6” diameter, 303 feet deep, spaced at 30’ centers. Total loopfield
area equals 0.7 acre. For cost estimating purposes, it is assumed that the loopfield will be installed as
part of the parking lot renovation project that is currently in design.
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Cooling
The ventilation systems will utilize natural cooling the majority of the year. On warm summer days,
the loopfield will supply cooling water to the air handling units, via the hydronic piping system. The
heat will be injected into the ground, which will improve the loopfield temperature recharge for the
following heating season.
Seawater Heat Pump System
Heating
The heating system will consist of a water-to-water heat pump and the existing fuel oil boilers. The
heat pump is sized for 70% and the boilers for 100% of the design heating load. An energy analysis
determined that a heat pump sized for 70% of the design load will supply 95% of the heating
requirement. The boilers will supplement on cold days and during maintenance periods.
The heating and cooling systems will be similar to the GSHP system except that instead of a
loopfield, seawater will be used as the heat source. Either the groundwater (seawater) well and the
seawater intake concepts could be used for this option.
Cooling
The ventilation system will utilize natural cooling the majority of the year. On warm summer days,
the seawater will provide cooling for the air handling units, via the hydronic piping system.
Air Source Heat Pump System
The air source heat pump systems will use heat pumps to supply heating and cooling to the building.
Ventilation is provided by energy recovery ventilators that extract heat from exhaust air to preheat the
ventilation air. Each thermal zone will have a fan coil unit that maintains thermal comfort by heating
or cooling the space.
The heat pumps will be installed inside a louvered enclosure that protects the equipment and mitigates
noise. For the purpose of this analysis, it is assumed that a portion of the mechanical lofts will be
converted to such a space.
A conceptual layout of the system consists of the following equipment:
Auditorium: One energy recovery ventilator (ERV) supplying ventilation air to four fan coil
units; heating and cooling supplied by two outdoor heat pumps.
Meeting Rooms / Offices / Storage: An ERV supplying ventilation air to eight fan coils on the
east side, one ERV supplying ventilation air to nine fan coil units on the east side; heating and
cooling supplied by two outdoor heat pump units.
Museum: An ERV supplying ventilation air to six fan coil units; heating and cooling supplied by
two outdoor heat pump units.
This system will not provide natural cooling. Due to the high cost of integrating the existing fuel oil
boilers and hydronic heating system into the fan coil units, the system would be demolished and
backup heat supplied by electric heating coils.
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LIFE CYCLE COST ANALYSIS
The analysis compares the life cycle cost of the baseline HVAC system, ground source heat pump
systems, seawater well heat pump systems, seawater intake heat pump system, and air source heat
pump system. Conceptual diagrams of the heat pump systems are provided in Appendix A. Sizing
and life cycle cost calculations are provided in Appendix B.
Construction Costs
The heat pump options will require an investment of $140K to $1,700K over the baseline system. The
following table compares the cost of the systems.
Construction Costs – Centennial Hall
Construction Scope Cost Estimate Budget Increase
Baseline HVAC System $ 1,970,000 -
Ground Source Heat Pump System $ 3,060,000 $ 1,090,000
Groundwater Well Heat Pump System $ 2,850,000 $ 880,000
Seawater Intake Heat Pump System $ 3,650,000 $ 1,680,000
Air Source Heat Pump System $ 2,110,000 $ 140,000
Assumptions
Baseline: The fuel oil boilers have 22 years of remaining life. The ventilation and cooling systems
will be replaced in the renovation project.
Electrical Service: It is assumed that the capacity of the building electric service will be increased
under the expansion project. The added cost for further increasing the size of the electric service to
supply the heat pumps is included in each option.
Operating Costs
The following table summarizes the operating costs for each option. The basis for these costs is
provided in the Life Cycle Cost Methodology Section.
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Operating Costs – Centennial Hall
System Annual Cost 1 Life Cycle Cost 2
Baseline HVAC System
Maintenance and Repair $ 9,500 $ 200,000
Replacement - 50,000
Total $ 9,500 $ 250,000
Ground Source Heat Pump System
Maintenance and Repair $ 8,000 $ 170,000
Replacement - 50,000
Total Maintenance and Repair $ 8,000 $ 220,000
Loopfield Salvage Value 3 - ($ 100,000)
Net $ 8,000 $ 120,000
Groundwater Well Heat Pump System
Maintenance and Repair $ 9,400 $ 190,000
Replacement - 60,000
Total $ 9,400 $ 250,000
Seawater Intake Heat Pump System
Maintenance and Repair $ 9,900 $ 200,000
Replacement - 60,000
Total $ 9,900 $ 260,000
Air Source Heat Pump System
Maintenance and Repair $ 33,000 $ 690,000
Replacement - 150,000
Total $ 33,000 $ 840,000
1. Annual costs include regular and intermittent maintenance and repair costs that have been averaged
over an annual basis.
2. Life cycle cost includes equipment replacement costs at the end of its service life.
3. Includes remaining value of loopfield at the end of 30-year analysis period.
4. Note: Negative values (in parenthesis) represent savings.
Ground Source Heat Pump System: This system has the lowest operating costs. When compared to
the baseline system, the loopfield negates the need for cooling equipment and the heat pump reduces
the amount of boiler maintenance. These reductions more than offset the added heat pump
maintenance.
Baseline System: This system has the next lowest operating costs. The equipment maintenance can
all be accomplished in-house and the remaining service life that exceeds the 30-year analysis period.
Seawater Heat Pump Systems: These systems have higher operating costs due to intake/discharge
cleaning requirements and cleaning the seawater heat exchanger and piping.
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The air-source heat pump system has the highest operating costs because it has more equipment that
requires maintenance, the outdoor units will require replacement every 12 years due to corrosion in
Sitka’s salt-laden environment, and the fan coils and energy recovery ventilators will require
replacement in 20 years.
Energy Consumption and Costs
Baseline HVAC System
The energy analysis is based on the fuel oil boiler supplying 100% of the heating load. Energy use of
the renovated building was predicted based on the following adjustments from the existing building:
Energy reduction due to new natural cooling systems -12%
Efficiency improvements to envelope -10%
Increase in building area 45%
Energy use increase due to higher museum requirements 8%
Total 31%
The boilers will supply heat to the building, natural cooling will provide most of the cooling with
supplemental mechanical cooling on warm days, and pumps will distribute the heat to the building.
The baseline system has the highest energy costs due to low conversion efficiency of fuel oil boilers
and higher fuel oil inflation.
Ground Source Heat Pump System
The heat pump is sized for 50% of the design heating load and will supply 80% of the heat at a
seasonal efficiency of 290%. The energy cost of the ground source heat pump system is higher than
the seawater system because the ground is colder, higher pumping costs to circulate water through the
loopfield, and fuel oil supplementation during cold weather. The loopfield will supply water directly
to the AHUs coils for cooling.
Seawater Heat Pump Systems
The heat pump is sized for 70% of the design heating load and will supply 95% of the heat at seasonal
efficiency of 360%. The seawater heat pump systems benefit from their high conversion efficiency to
have the lowest energy costs. This efficiency is higher than the GSHP system due to warmer seawater
temperatures during the heating season. Natural cooling will be supplemented by loopfield water
supplied directly to the AHUs coils on warm days.
Air Source Heat Pump System
The heat pumps will supply 95% of the heating load at a seasonal efficiency of 220%. Electric coils in
each fan coil unit and heat recovery ventilator will supply heat when the outdoor units are in defrost
mode or require maintenance. The system does not provide natural cooling so the heat pumps will
also supply cooling at an efficiency of 390%.
The air source heat pump system has a lower efficiency than the ground source or seawater heat
pumps; however it uses electricity for backup heat at a lower inflation rate, which causes it to have
only slightly higher energy costs.
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Energy Consumption and Costs – Centennial Hall
Energy Costs Annual Energy Life Cycle
Consumption 2013 Cost Energy Cost
Baseline HVAC System
Fuel Oil 12,200 gals $ 49,000 $ 1,730,000
Electricity 25,000 kWh 3,000 60,000
Total $ 52,000 $ 1,790,000
Ground Source Heat Pump System
Fuel Oil 2,400 gals $ 10,000 $ 350,000
Electricity 136,000 kWh 15,000 340,000
Total $ 25,000 $ 690,000
Groundwater Well Heat Pump System
Fuel Oil 600 gals $ 3,000 $ 90,000
Electricity 123,000 kWh 13,000 310,000
Total $ 16,000 $ 400,000
Seawater Intake Heat Pump System
Fuel Oil 600 gals $ 3,000 $ 90,000
Electricity 123,000 kWh 13,000 310,000
Total $ 16,000 $ 400,000
Air Source Heat Pump System
Fuel Oil 0 gals $ 0 $ 0
Electricity 159,000 kWh 17,000 400,000
Total $ 17,000 $ 400,000
Life Cycle Cost Comparison
A life cycle cost comparison of the options shows that the seawater well heat pump system and the air
source heat pump system have similar life cycle costs.
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Life Cycle Cost Comparison – Centennial Hall
Heating System Construction Maintenance Energy Total LCC
Base Case: 6.6% Fuel Oil, 2.5% Electricity
Baseline HVAC System $1,970,000 $250,000 $1,790,000 $4,010,000
Ground Source Heat Pump System $3,060,000 $120,000 $690,000 $3,870,000
Groundwater Well Heat Pump System $2,850,000 $250,000 $400,000 $3,500,000
Seawater Intake Heat Pump System $3,650,000 $260,000 $400,000 $4,310,000
Air-source Heat Pump System $2,110,000 $840,000 $400,000 $3,350,000
High Fuel Oil Case: 8% Fuel Oil, 2.5% Electricity
Baseline HVAC System $1,970,000 $250,000 $2,210,000 $4,430,000
Ground Source Heat Pump System $3,060,000 $120,000 $770,000 $3,950,000
Groundwater Well Heat Pump System $2,850,000 $250,000 $420,000 $3,520,000
Seawater Intake Heat Pump System $3,650,000 $260,000 $420,000 $4,330,000
Air-source Heat Pump System $2,110,000 $840,000 $400,000 $3,350,000
Low Fuel Oil Case: 4.8% Fuel Oil, 2.5% Electricity
Baseline HVAC System $1,970,000 $250,000 $1,390,000 $3,610,000
Ground Source Heat Pump System $3,060,000 $120,000 $610,000 $3,790,000
Groundwater Well Heat Pump System $2,850,000 $250,000 $380,000 $3,480,000
Seawater Intake Heat Pump System $3,650,000 $260,000 $380,000 $4,290,000
Air-source Heat Pump System $2,110,000 $840,000 $400,000 $3,350,000
High Electricity Case: 6.6% Fuel Oil, 4% Electricity
Baseline HVAC System $1,970,000 $250,000 $1,800,000 $4,020,000
Ground Source Heat Pump System $3,060,000 $120,000 $750,000 $3,930,000
Groundwater Well Heat Pump System $2,850,000 $250,000 $450,000 $3,550,000
Seawater Intake Heat Pump System $3,650,000 $260,000 $450,000 $4,360,000
Air-source Heat Pump System $2,110,000 $840,000 $470,000 $3,420,000
Low Electricity Case: 6.6% Fuel Oil, 1% Electricity
Baseline HVAC System $1,970,000 $250,000 $1,780,000 $4,000,000
Ground Source Heat Pump System $3,060,000 $120,000 $640,000 $3,820,000
Groundwater Well Heat Pump System $2,850,000 $250,000 $350,000 $3,450,000
Seawater Intake Heat Pump System $3,650,000 $260,000 $350,000 $4,260,000
Air-source Heat Pump System $2,110,000 $840,000 $340,000 $3,290,000
Note: Highlighted costs are lowest life cycle cost in each category. Where two values are highlighted represents
options that have essentially equal life cycle cost within the accuracy of the feasibility analysis.
Energy costs are typically the largest component of the total life cycle cost of a heating system. While
this is true here, the heating options require significant investment which also factor greatly into
overall life cycle cost. For any of the options to be preferred over the relatively lower construction
cost of the baseline system—likely siphoning dollars from other priorities—the system should
overwhelmingly have a lower life cycle cost. All of the options and scenarios have a life cycle cost of
$3.8M+/- 10%, which is very close when estimating and forecasting costs for 30 years.
In this analysis, the air source heat pump system and the seawater well heat pump system have
essentially equal life cycle costs under all scenarios. The air source heat pump system requires a
lower investment while the seawater system has lower maintenance and energy costs. The seawater
system can be expanded to include the library but it also requires a permitting process and ongoing
permitting requirements.
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Section 5
Existing Kettleson Memorial Library
INTRODUCTION
The existing Library is 7,500 sqft and is heated by a fuel oil boiler which supplies heating water to
heating coils in the ventilation systems. There is no mechanical cooling.
A heat pump system that retains the existing HVAC systems will offer the greatest financial
conversion incentive. Two options readily present themselves:
Convert the hydronic heating system from high temperature (180°F) to low temperature (115°F)
and install water-side heat pumps. To deliver sufficient heat using lower temperature water, the
hydronic heating coils in the ventilation systems must be replaced with coils with more heat
transfer surface area. A water-side heat pump will supply the majority of the heat with the
existing boiler supplementing during cold weather.
Retain the existing hydronic system and install an air-side heat pump system. The system will
consist of outdoor heat pumps supplying heat to additional ventilation system heating coils
located adjacent to the existing hydronic coils.
There is also an air source heat pump option that is capable of supplying 160°F heating water.
This option would likely not require any modification to the existing hydronic heating system as
long as it is oversized sufficiently to supply enough heat during cold weather. This system
requires more equipment at greater cost and has a lower efficiency than the low temperature
option. While it may eliminate the need to convert the existing hydronic heating system, the
higher first cost and lower efficiency eliminated it from consideration. This option has the
following components:
1. One outdoor heat pump unit
2. A central control unit to distribute the hot refrigerant from the outdoor unit to the indoor
units.
3. Six indoor booster heat pumps that lift the heat from the outdoor units to produce 160°F
heating supply water.
Converting the hydronic heating system to a low temperature system is the preferred option. It retains
the fuel oil boilers as a second energy source, is less complex from a control and maintenance
perspective, and has the least impact on the performance of the existing fans.
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HEATING SYSTEM OPTIONS
Status Quo
The existing fuel oil boiler and ventilation systems are retained to heat and ventilate the building.
Ground Source Heat Pump
The heating system consists of a water-to-water heat pump and fuel oil boilers. The heat pump is
sized for 50% and the boilers for 100% of the design heating load. An energy analysis determined
that a heat pump sized for 50% of the design load will supply 80% of the heating requirement. Since a
GSHP system has high capital costs for coupling to the ground, this sizing will reduce the ground
couple investment while optimizing the amount of extracted heat.
Installation of a geothermal loopfield will require mobilization of a geothermal contractor to Sitka.
The library building will not generate sufficient energy savings to offset the high cost of mobilization
and installation of the loopfield. Therefore, the ground source analysis is based on the assumption that
a geothermal contractor is already mobilized to Sitka, perhaps installing a loopfield for the Centennial
Building Renovation.
Preliminary sizing is 10 boreholes, 6” diameter, 294 feet deep, spaced at 30’ centers. Total loopfield
area equals 0.2 acres.
Seawater Heat Pump
The heating system will consist of a water-to-water heat pump and the existing fuel oil boiler. The
heat pump is sized for 70% and the boilers for 100% of the design heating load. The heat pump will
extract heat from seawater and discharge it to the adjacent storm sewer.
The library building will not generate sufficient energy savings to offset the high cost of constructing
a groundwater well or seawater intake. As such, the seawater analysis is based on the assumption that
a well or intake is constructed for the Centennial Building and that the library is added onto that
system. The library analysis includes the cost of increasing the capacity of the seawater system by 50
gpm of seawater flow at peak capacity.
The seawater from the Centennial Building will be piped in direct-bury piping to the building and
flow through a titanium heat exchanger in an expanded Library mechanical room. The seawater is
then discharged to the ocean.
The heat pump and existing boiler will be coupled to a heating tank that will provide thermal mass for
the heat pump system. Automatic controls will operate the heat pump (lead) and boiler (lag) to
maintain tank temperature.
Air Source Heat Pumps
The system will utilize two air-source heat pumps to supply hydronic heating water to the building.
The outdoor unit will be installed in a louvered enclosure under the existing building eve— to
preclude blowing snow plugging the unit and to mitigate noise impacts—with the discharge air
ducted outside.
The heat pumps and existing boiler will be coupled to a heating tank that will provide thermal mass
for the heat pump system. Automatic controls will operate the heat pump (lead) and boiler (lag) to
maintain tank temperature.
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LIFE CYCLE COST ANALYSIS
The analysis compares the life cycle cost of the baseline HVAC system, ground source heat pump
system, seawater heat pump system, and air source heat pump system. Conceptual diagrams of the
heat pump systems are provided in Appendix C. Sizing and life cycle cost calculations are provided in
Appendix D.
Construction Costs
The existing heating and ventilating systems are in very good condition and will not require major
equipment replacement in the next 30 years. The investment to incorporate heat pumps into the
building ranges from $292K to $488K, depending upon which option is preferred. The following
table compares the cost of the options.
Construction Costs – Existing Library
Options Cost Estimate
Baseline: Retain Fuel Oil Boiler System $ 0
Ground Source Heat Pump System $ 488,000
Seawater Heat Pump System 1 $ 466,000
Air Source Heat Pump System $ 390,000
1. Cost assumes the system connects to a seawater source (either groundwater well or
seawater intake) that serves the Centennial Building.
Assumptions
Seawater Heat Pump System: Seawater will be supplied from a water well or seawater intake as part
of the Centennial Hall Renovation.
Electrical Service: A preliminary calculation determined that the existing electric service is large
enough to supply the heat pump options. A demand meter is required to verify that sufficient capacity
is available.
Operating Costs
The following table summarizes the operating costs for each option. The basis for these costs is
provided in the Life Cycle Cost Methodology Section.
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Operating Costs – Existing Library
System Annual Cost 1 Life Cycle Cost 2
Existing HVAC System
Maintenance and Repair $ 5,200 $ 109,000
Ground Source Heat Pump System
Maintenance and Repair $ 5,900 $ 122,000
Replacement - 15,000
Subtotal $ 5,900 $ 137,000
Loopfield Salvage Value 3 - ($ 30,000)
Net $ 5,900 $ 107,000
Seawater Heat Pump System
Maintenance and Repair $ 6,800 $ 142,000
Replacement - 18,000
Total $ 6,800 $ 160,000
Air Source Heat Pump System
Maintenance and Repair $ 8,800 $ 183,000
Replacement - 48,000
Total $ 8,800 $ 231,000
1. Annual costs include regular and intermittent maintenance and repair costs that have been averaged over
an annual basis.
2. Life cycle cost includes equipment replacement costs at the end of its service life.
3. Includes remaining value of loopfield at the end of the analysis period.
4. Note: Negative values (in parenthesis) represent savings.
The existing baseline systems have the lowest operating costs because none of the equipment will
require replacement during the 30-year analysis period.
The ground source heat pump system has the next lowest operating costs. This system has higher
operating costs because of heat pump replacement costs. The loopfield salvage value brings the net
operating costs down equal to the baseline system.
The air-source heat pump system has the highest operating costs due to maintenance, repair, and
replacement of the outdoor heat pump units.
Energy Consumption and Costs
Baseline HVAC System
The energy analysis is based on the fuel oil boiler supplying 100% of the heating load. Heating
energy use is predicted to be the average of 4,000 gallons over the past two years.
Ground Source Heat Pump System
The heat pump is sized for 50% of the design heating load and will supply 80% of the heat at a
seasonal efficiency of 290%.
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Seawater Heat Pump System
The heat pump is sized for 70% of the design heating load and will supply 95% of the heat at seasonal
efficiency of 360%. This efficiency is higher than the GSHP system due to warmer seawater
temperatures during the heating season. Natural cooling will be supplemented by loopfield water
supplied directly to the AHUs coils on warm days.
Air Source Heat Pump System
The heat pumps will supply 95% of the heating load at a seasonal efficiency of 220%. The boiler
provides supplemental heat when the outdoor units are in defrost mode or require maintenance.
Energy Consumption and Costs – Existing Library
Energy Costs Annual Energy Life Cycle
Consumption 2013 Cost Energy Cost
Baseline HVAC System
Fuel Oil 4,000 gals $ 16,000 $567,000
Electricity 480 kWh 50 1,000
Total $ 16,000 $ 568,000
Ground Source Heat Pump System
Fuel Oil 800 gals $ 3,200 $ 113,000
Electricity 42,000 kWh 4,500 104,000
Total $ 7,700 $ 217,000
Seawater Heat Pump System
Fuel Oil 200 gals $ 800 $ 28,000
Electricity 43,000 kWh 4,700 108,000
Total $ 5,500 $ 136,000
Air Source Heat Pump System
Fuel Oil 200 gals $ 800 $ 28,000
Electricity 52,000 kWh 5,700 131,000
Total $ 6,500 $ 159,000
The seawater heat pump system benefits from its high conversion efficiency to have the lowest
energy costs. The air source heat pump system has a slightly lower efficiency and correspondingly
higher energy costs. The energy cost of the ground source heat pump system is higher due to pumping
costs to circulate water through the loopfield and greater fuel oil supplementation during cold
weather. The baseline system has the highest energy costs due to the low conversion efficiency of fuel
oil boilers and higher fuel oil inflation.
Life Cycle Cost Comparison
A life cycle cost comparison shows that the baseline system has the lowest life cycle cost. The air
source heat pump system is able to offset higher construction and maintenance costs with energy
savings to produce the next lowest life cycle cost. This finding indicates the high cost of retrofitting a
heat pump system into the existing building is not offset by energy savings.
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A sensitivity analysis was applied to determine how modest variations in energy inflation affect the
findings. The following adjustments were made:
To account for increasing fuel oil price volatility, fuel oil inflation (base = 6.6%) was varied from
8% to 4.8%.
To account for a possible drop or increase in the electric load, electricity inflation (base = 2.5%)
was varied from 4% to 1%.
Life Cycle Cost Comparison – Existing Library
Heating System Construction Maintenance Energy Total LCC
Base Case: 6.6% Fuel Oil, 2.5% Electricity
Baseline Fuel Oil Boilers $0 $110,000 $570,000 $680,000
Ground Source Heat Pump System $490,000 $110,000 $220,000 $810,000
Seawater Heat Pump System $470,000 $160,000 $140,000 $760,000
Air Source Heat Pump System $390,000 $230,000 $160,000 $780,000
High Fuel Oil Case: 8% Fuel Oil, 2.5% Electricity
Baseline Fuel Oil Boilers $0 $110,000 $710,000 $820,000
Ground Source Heat Pump System $490,000 $110,000 $250,000 $840,000
Seawater Heat Pump System $470,000 $160,000 $140,000 $770,000
Air Source Heat Pump System $390,000 $230,000 $170,000 $790,000
Low Fuel Oil Case: 4.8% Fuel Oil, 2.5% Electricity
Baseline Fuel Oil Boilers $0 $110,000 $440,000 $550,000
Ground Source Heat Pump System $490,000 $110,000 $190,000 $790,000
Seawater Heat Pump System $470,000 $160,000 $130,000 $760,000
Air Source Heat Pump System $390,000 $230,000 $150,000 $770,000
High Electricity Case: 6.6% Fuel Oil, 4% Electricity
Baseline Fuel Oil Boilers $0 $110,000 $570,000 $680,000
Ground Source Heat Pump System $490,000 $110,000 $240,000 $830,000
Seawater Heat Pump System $470,000 $160,000 $160,000 $780,000
Air Source Heat Pump System $390,000 $230,000 $180,000 $810,000
Low Electricity Case: 6.6% Fuel Oil, 1% Electricity
Baseline Fuel Oil Boilers $0 $110,000 $570,000 $680,000
Ground Source Heat Pump System $490,000 $110,000 $200,000 $800,000
Seawater Heat Pump System $470,000 $160,000 $120,000 $750,000
Air Source Heat Pump System $390,000 $230,000 $140,000 $760,000
Note: Highlighted costs are lowest cost in each category.
Energy costs are typically the largest component of the total life cycle cost of a heating system. But
with heat pump systems, we find that the construction costs (investment) are a higher percentage of
life cycle costs.
The sensitivity analysis continues to show that the baseline system has the lowest life cycle cost. Only
under the scenario of high fuel oil inflation does the seawater source heat pump system offer the
lowest life cycle cost.
Alaska Energy Engineering LLC
Centennial Hall and Library 33 Renewable Energy Feasibility Analysis
For any of the options to be preferred over the zero cost of the baseline system—likely siphoning
dollars from other priorities—the system should overwhelmingly have a lower life cycle cost. This is
not the case here. However, the seawater source heat pump system does compete favorably if fuel oil
prices are higher than the baseline and it also offers other benefits when factors such as renewable
energy, lower greenhouse gas emissions, and sustainability are considered.
This finding is representative of the challenges of retrofitting heat pumps into an existing building.
The Library is a relatively small building with modest energy requirements. A heat pump system does
not generate sufficient energy savings to offset the high cost of retrofit. The economics of the
seawater source system are more comparable because it is assumed to tie into the potential Centennial
Hall seawater infrastructure.
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Centennial Hall and Library 34 Renewable Energy Feasibility Analysis
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Centennial Hall and Library 35 Renewable Energy Feasibility Analysis
Section 6
Renovated Kettleson Memorial Library
INTRODUCTION
A project to renovated and expand the Library has been proposed. This analysis will determine
whether it is feasible during a 60% expansion project to convert the Library from fuel oil boiler heat
to renewable heat pumps.
The expansion will likely require complete replacement of the HVAC systems. The analysis assumes
the renovated building will include upgrades to the thermal envelope of the building, reducing heating
costs by 20%.
The proposed expansion and renovation project provides an excellent opportunity to convert the
building to heat pump technologies. The new ventilation systems can be readily designed for heat
pump applications for a modest investment.
HEATING SYSTEM OPTIONS
Baseline HVAC System
A traditional system that retains the fuel oil boiler and hydronic heating system and replaces the
ventilation systems with variable air volume reheat systems is used as the baseline for this analysis.
Further optimization of the HVAC systems is likely to occur in the design phase of the project.
The library is currently heated by a fuel oil boiler. Preliminary calculations indicate that the existing
boiler has sufficient capacity for the expanded building.
The baseline HVAC system consists of:
Heating: Existing fuel oil boiler
Cooling: Natural cooling with outside air
Ventilation: Variable air volume ventilation system.
Ground Source Heat Pump System
This option adds a ground source heat pump to the baseline system to heat the building and retains the
existing fuel oil boiler to supplement when needed. The heat pump is sized for 50% and the boilers
for 100% of the design heating load. An energy analysis determined that a heat pump sized for 50%
of the design load will supply 80% of the heating requirement. Since a GSHP system has high capital
costs for coupling to the ground, this sizing will reduce the investment while optimizing the amount
of extracted heat.
The ground source heat pump will utilize a vertical loopfield located under the parking area.
Preliminary sizing is: 12 boreholes, 6” diameter, 313 feet deep, spaced at 30’ centers. Total loopfield
area equals 0.2 acre.
Alaska Energy Engineering LLC
Centennial Hall and Library 36 Renewable Energy Feasibility Analysis
Seawater Heat Pump
The heating system will consist of a water-to-water heat pump and the existing fuel oil boiler. The
heat pump is sized for 70% and the boiler for 100% of the design heating load. The heat pump will
extract heat from seawater and discharge it to the adjacent storm sewer.
The library building will not generate sufficient energy savings to offset the high cost of a seawater
system. Therefore, the seawater analysis is based on the assumption that a well or intake is
constructed for the Centennial Building and that the library is added onto that system. The library
analysis includes the cost of increasing the capacity of the Centennial Hall seawater system by 65
gpm of seawater flow at peak capacity.
The seawater from the Centennial Building will be supplied to the building via direct-bury piping and
flow through a titanium heat exchanger in an expanded Library mechanical room. The seawater is
discharged to the ocean.
Air Source Heat Pump System
This system will use two heat pumps to supply heating and cooling to the building. Ventilation is
provided by an energy recovery ventilator that extracts heat from exhaust air to preheat the ventilation
air. The heat is transferred to/from fan coil units distributed throughout the building. Each thermal
zone will have a fan coil unit that maintains thermal comfort by heating or cooling the space.
This system is systemically more efficient than the baseline because it ventilates, heats, and cools
each space as required rather than performing these functions at the system level. It also can move
heat around within the building.
A louvered enclosure that protects the equipment and mitigates noise is the preferred location for the
heat pumps. This analysis assumes that this enclosure will be added under the eve on the west side of
the building.
A conceptual layout of the system consists of one energy recovery ventilator (ERV) supplying
ventilation air to ten fan coil units with heating and cooling supplied by two outdoor heat pumps.
Due to the high cost of integrating the existing hydronic heating system into the fan coil units, the
hydronic heating system is deleted and backup heat is supplied by electric heating coils during times
the heat pump is defrosting or is out of service for maintenance and repair.
LIFE CYCLE COST ANALYSIS
The analysis compares the life cycle cost of the baseline HVAC system, ground source heat pump
system, seawater heat pump system, and air source heat pump system. Conceptual diagrams of the
heat pump systems are provided in Appendix C. Sizing and life cycle cost calculations are provided in
Appendix D.
Construction Costs
The HVAC options will require an investment of $99K to $231K over the baseline system. The
following table compares the cost of the systems.
Alaska Energy Engineering LLC
Centennial Hall and Library 37 Renewable Energy Feasibility Analysis
Construction Costs – Renovated Library
Construction Scope Cost Estimate Budget Increase
Baseline HVAC System $ 392,000 -
Ground Source Heat Pump System $ 623,000 $ 231,000
Seawater Well Heat Pump System $ 491,000 $ 99,000
Air Source Heat Pump System $ 560,000 $ 168,000
Assumptions
Baseline: The fuel oil boiler has 30 years of remaining life. The ventilation systems will be replaced
in the renovation project.
Seawater Heat Pump System: It is assumed that a seawater system for Centennial Hall will produce
seawater of sufficient quality and capacity (65 gpm) to supply seawater to the Library.
Electrical Service: It is assumed that the capacity of the building electric service will be increased
under the expansion project. The added cost for further increasing the size of the electric service to
supply the heat pumps is included in each option.
Operating Costs
The following table summarizes the operating costs for each option. The basis for these costs is
provided in the Life Cycle Cost Methodology Section.
Alaska Energy Engineering LLC
Centennial Hall and Library 38 Renewable Energy Feasibility Analysis
Operating Costs – Renovated Library
System Annual Cost 1 Life Cycle Cost 2
Baseline HVAC System
Maintenance and Repair $ 6,600 $ 138,000
Replacement - -
Total $ 6,600 $ 138,000
Ground Source Heat Pump System
Maintenance and Repair $ 8,200 $ 171,000
Replacement - 18,000
Total Maintenance and Repair $ 8,200 $ 189,000
Loopfield Salvage Value 3 - ($ 38,000)
Net $ 8,200 $ 151,000
Seawater Well Heat Pump System
Maintenance and Repair $ 8,400 $ 176,000
Replacement - 18,000
Total $ 8,400 $ 194,000
Air Source Heat Pump System
Maintenance and Repair $ 12,500 $ 261,000
Replacement - 41,000
Total $ 12,500 $ 302,000
1. Annual costs include regular and intermittent maintenance and repair costs that have been averaged
on an annual basis.
2. Life cycle cost includes equipment replacement costs at the end of its service life.
3. Includes remaining value of loopfield at the end of 30-year analysis period.
4. Note: Negative values (in parenthesis) represent savings.
The baseline system has the lowest operating costs. The equipment requires the least amount of
maintenance and all of it has a service life that exceeds the 30-year analysis period.
The ground source heat pump system has the next lowest operating costs. When compared to the
baseline system, the heat pump reduces the amount of boiler maintenance.
The seawater well heat pump system has higher operating costs due to cleaning the seawater heat
exchanger and piping.
The air-source heat pump system has the highest operating costs because it has more equipment that
requires maintenance, the outdoor units will require replacement every 12 years due to corrosion in
Sitka’s salt-laden environment, and the fan coils and energy recovery ventilators will require
replacement.
Alaska Energy Engineering LLC
Centennial Hall and Library 39 Renewable Energy Feasibility Analysis
Energy Consumption and Costs
Baseline HVAC System
The energy analysis is based on the fuel oil boiler supplying 100% of the heating load. Energy use of
the renovated building was predicted based on the following adjustments from the existing building:
Efficiency improvements -20%
Increase in building area 60%
Total 40%
The boilers will supply heat to the building, air handling system will provide natural cooling, and
pumps will distribute the heat to the building.
The baseline system has the highest energy costs due to the low conversion efficiency of fuel oil
boilers and higher fuel oil inflation.
Ground Source Heat Pump System
The heat pump is sized for 50% of the design heating load and will supply 80% of the heat at a
seasonal efficiency of 290%. The loopfield will supply water directly to the AHUs coils for cooling.
The energy cost of the ground source heat pump system is higher than the seawater system due to its
lower conversion efficiency, higher pumping energy requirements, and fuel oil supplementation
during cold weather.
Seawater Heat Pump System
The heat pump is sized for 70% of the design heating load and will supply 95% of the heat at seasonal
efficiency of 360%. This efficiency is higher than the GSHP system due to warmer seawater
temperatures during the heating season. The ventilation systems will provide natural cooling.
The seawater heat pump system benefits from its high conversion efficiency to have the lowest
energy costs.
Air Source Heat Pump System
The heat pumps will supply 95% of the heating load at a seasonal efficiency of 220%. Electric coils in
each fan coil unit and heat recovery ventilator will supply heat when the outdoor units are in defrost
mode or require maintenance. The system does not provide natural cooling so the heat pumps will
also supply cooling at an efficiency of 390%.
The air source heat pump system has a lower efficiency than the other two heat pump systems.
However, it uses electricity for backup heat at a lower inflation rate, which causes it to have only
slightly higher life cycle energy costs.
Alaska Energy Engineering LLC
Centennial Hall and Library 40 Renewable Energy Feasibility Analysis
Energy Consumption and Costs – Renovated Library
Energy Costs Annual Energy Life Cycle
Consumption 2013 Cost Energy Cost
Baseline HVAC System
Fuel Oil 5,600 gals $ 22,000 $ 794,000
Electricity 600 kWh 70 2,000
Total $ 22,000 $ 796,000
Ground Source Heat Pump System
Fuel Oil 280 gals $ 1,000 $ 40,000
Electricity 60,000 kWh 7,000 150,000
Total $ 8,000 $ 190,000
Seawater Well Heat Pump System
Fuel Oil 280 gals $ 1,000 $ 40,000
Electricity 55,000 kWh 6,000 137,000
Total $ 7,000 $ 177,000
Air Source Heat Pump System
Fuel Oil 0 gals $ 0 $ 0
Electricity 73,000 kWh 8,000 182,000
Total $ 8,000 $ 182,000
Life Cycle Cost Comparison
A life cycle cost comparison of the options shows that the seawater well heat pump system has the
lowest life cycle cost. This result occurs because it is assumed that the cost of coupling to the sea is
limited to the incremental cost increase required to add the building to a potential Centennial Hall
seawater system.
A sensitivity analysis was applied to determine how modest variations in energy inflation affect the
findings. The following adjustments were made:
To account for increasing fuel oil price volatility, fuel oil inflation (base = 6.6%) was varied from
8% to 4.8%.
To account for a possible drop or increase in the electric load, electricity inflation (base = 2.5%)
was varied from 4% to 1%.
Alaska Energy Engineering LLC
Centennial Hall and Library 41 Renewable Energy Feasibility Analysis
Life Cycle Cost Comparison – Renovated Library
Heating System Construction Maintenance Energy Total LCC
Base Case: 6.6% Fuel Oil, 2.5% Electricity
Baseline Fuel Oil Boilers $390,000 $140,000 $800,000 $1,330,000
Ground Source Heat Pump System $620,000 $150,000 $190,000 $960,000
Seawater Heat Pump System $490,000 $190,000 $180,000 $860,000
Air Source Heat Pump System $560,000 $300,000 $180,000 $1,040,000
High Fuel Oil Case: 8% Fuel Oil, 2.5% Electricity
Baseline Fuel Oil Boilers $390,000 $140,000 $990,000 $1,520,000
Ground Source Heat Pump System $620,000 $150,000 $200,000 $970,000
Seawater Heat Pump System $490,000 $190,000 $190,000 $870,000
Air Source Heat Pump System $560,000 $300,000 $180,000 $1,040,000
Low Fuel Oil Case: 4.8% Fuel Oil, 2.5% Electricity
Baseline Fuel Oil Boilers $390,000 $140,000 $610,000 $1,140,000
Ground Source Heat Pump System $620,000 $150,000 $180,000 $960,000
Seawater Heat Pump System $490,000 $190,000 $170,000 $850,000
Air Source Heat Pump System $560,000 $300,000 $180,000 $1,040,000
High Electricity Case: 6.6% Fuel Oil, 4% Electricity
Baseline Fuel Oil Boilers $390,000 $140,000 $800,000 $1,330,000
Ground Source Heat Pump System $620,000 $150,000 $220,000 $990,000
Seawater Heat Pump System $490,000 $190,000 $200,000 $890,000
Air Source Heat Pump System $560,000 $300,000 $220,000 $1,080,000
Low Electricity Case: 6.6% Fuel Oil, 1% Electricity
Baseline Fuel Oil Boilers $390,000 $140,000 $800,000 $1,330,000
Ground Source Heat Pump System $620,000 $150,000 $170,000 $940,000
Seawater Heat Pump System $490,000 $190,000 $160,000 $840,000
Air Source Heat Pump System $560,000 $300,000 $150,000 $1,010,000
Note: Highlight indicated lowest cost option.
Energy costs are typically the largest component of the total life cycle cost of a heating system. But
with heat pump systems, we find that the construction costs (investment) are a higher percentage of
life cycle costs. The higher energy use of the renovated building offers incentive to invest in a more
efficient heat pump system for the building.
The sensitivity analysis continues to show that the seawater well heat pump system offers the lowest
life cycle cost under all energy inflation scenarios.
For any of the options to be preferred over the relatively lower construction cost of the baseline
system—likely siphoning dollars from other priorities—the system should overwhelmingly have a
lower life cycle cost. This is the case with the seawater heat pump system as long as the intake
infrastructure is constructed when Centennial Hall is renovated.
If the seawater intake is not constructed, the ground source heat pump option has the lowest life cycle
cost under all energy inflation scenarios. Again, this analysis assumes that the mobilization costs for
the loopfield are shared with Centennial Hall.
The air source heat pump system is preferred if the loopfield mobilization or the seawater couple
costs cannot be shared with the Centennial Building renovation.
Alaska Energy Engineering LLC
Centennial Hall and Library 42 Renewable Energy Feasibility Analysis
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Alaska Energy Engineering LLC
Appendix A
Centennial Hall Schematic Diagrams
Alaska Energy Engineering LLC
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Alaska Energy Engineering LLC25200 Amalga Harbor RoadJuneau, Alaska 99801Phone and Fax: (907) 789-1226E-mail: jim@alaskaenergy.us
Alaska Energy Engineering LLC25200 Amalga Harbor RoadJuneau, Alaska 99801Phone and Fax: (907) 789-1226E-mail: jim@alaskaenergy.us
Alaska Energy Engineering LLC25200 Amalga Harbor RoadJuneau, Alaska 99801Phone and Fax: (907) 789-1226E-mail: jim@alaskaenergy.us
Alaska Energy Engineering LLC
Appendix B
Centennial Hall Sizing and Life Cycle Cost Calculations
Alaska Energy Engineering LLC
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25200 Amalga Harbor Road Tel/Fax: 907-789-1226
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Harrigan Centennial Hall Renewable Energy Feasibility Study
Heating System Optimization Analysis
Economic Factors Energy Inflation
Study Period (years) 30 Fuel Oil 6.6%
Nominal Discount Rate 5.5% Electricity, Yrs 1-2 9.0%
General Inflation 2.90% Electricity, Yrs 3-30 2.5%
Real Discount Rate 2.5%
Base Case: 6.6% Fuel Oil, 2.5% Electricity Construction Maintenance Energy Total
Baseline HVAC System $1,970,000 $250,000 $1,790,000 $4,010,000
Ground Source Heat Pump System $3,060,000 $120,000 $690,000 $3,870,000
Groundwater Well Heat Pump System $2,850,000 $250,000 $400,000 $3,500,000
Seawater Intake Heat Pump System $3,650,000 $260,000 $400,000 $4,310,000
Air-source Heat Pump System $2,110,000 $840,000 $400,000 $3,350,000
High Fuel Oil Case: 8% Fuel Oil, 2.5% Electricity Construction Maintenance Energy Total
Baseline HVAC System $1,970,000 $250,000 $2,210,000 $4,430,000
Ground Source Heat Pump System $3,060,000 $120,000 $770,000 $3,950,000
Groundwater Well Heat Pump System $2,850,000 $250,000 $420,000 $3,520,000
Seawater Intake Heat Pump System $3,650,000 $260,000 $420,000 $4,330,000
Air-source Heat Pump System $2,110,000 $840,000 $400,000 $3,350,000
Low Fuel Oil Case: 4.8% Fuel Oil, 2.5% Electricity Construction Maintenance Energy Total
Baseline HVAC System $1,970,000 $250,000 $1,390,000 $3,610,000
Ground Source Heat Pump System $3,060,000 $120,000 $610,000 $3,790,000
Groundwater Well Heat Pump System $2,850,000 $250,000 $380,000 $3,480,000
Seawater Intake Heat Pump System $3,650,000 $260,000 $380,000 $4,290,000
Air-source Heat Pump System $2,110,000 $840,000 $400,000 $3,350,000
High Electricity Case: 6.6% Fuel Oil, 4% Electricity Construction Maintenance Energy Total
Baseline HVAC System $1,970,000 $250,000 $1,800,000 $4,020,000
Ground Source Heat Pump System $3,060,000 $120,000 $750,000 $3,930,000
Groundwater Well Heat Pump System $2,850,000 $250,000 $450,000 $3,550,000
Seawater Intake Heat Pump System $3,650,000 $260,000 $450,000 $4,360,000
Air-source Heat Pump System $2,110,000 $840,000 $470,000 $3,420,000
Low Electricity Case: 6.6% Fuel Oil, 1% Electricity Construction Maintenance Energy Total
Baseline HVAC System $1,970,000 $250,000 $1,780,000 $4,000,000
Ground Source Heat Pump System $3,060,000 $120,000 $640,000 $3,820,000
Groundwater Well Heat Pump System $2,850,000 $250,000 $350,000 $3,450,000
Seawater Intake Heat Pump System $3,650,000 $260,000 $350,000 $4,260,000
Air-source Heat Pump System $2,110,000 $840,000 $340,000 $3,290,000
July 7, 2012
Present Worth
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Centennial Hall
STATUS QUO
Baseline HVAC System Area CFM/sqft CFM
AHU-1: Auditorium 5,725 1.25 7,200
VAV/RH with cooling coil, heating coil and CO2 control
AHU-2: Meetings and Offices 14,508 1.00 14,500
VAV/RH with cooling coil, heating coil and CO2 control
AHU-3: Museum 5,805 1.50 8,700
VAV/RH with cooling coil, heating coil and CO2 control
Total 26,038 30,400
Sizing
Existing Boilers Boiler Net MBH Factor Net MBH
B-1 704 100% 704
B-2 704 100% Area Btuh/sqft
704 21,600 33
Renovated Building Area Btuh/sqft MBH
31,000 30 930
Boiler Load MBH Factor Net MBH
B-1 930 76% 704
B-2 930 76% 704
1,408
Energy Consumption
Existing Building Use kBtu Area EUI
FO, Gal 8,000 1,108,000 21,600 89
Elect, kWh 240,520 820,654
1,928,654
Renovated Building Total kBtu
Existing Building 1,928,654
Natural cooling -12% -231,439
Efficiency gains -10% -192,865
Area increase 45% 867,894 Fuel Oil Electric Total Area EUI
Museum energy 8%154,292 67%33%
31% 2,526,537 1,692,780 833,757 2,526,537 31,000 82
Energy 2012 Price 2012 Cost 2013 Price 2013 Cost
Heating, gallons 12,200 $3.76 $45,872 $4.01 $48,900
Cooling, kWh 5% 24,761 $0.10 $2,476 $0.11 $2,699
$48,348 $51,599
July 7, 2012
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Centennial Hall
July 7, 2012
GROUND SOURCE HEAT PUMP
Sizing Heating Plant Load, MBH Factor Size, MBH kWh Tons COP kW
Heat pump 930 50% 465 - 39 3.0 45
B-1 930 76% 704
B-2 930 76% 704 - - - -
201% 1,873 0 39 45
Loopfield ft/ton Bore, lnft lnft/bore Bores Loops Bores/loop Spacing, ft Acres
250 9,688 303 32 2 16 30 0.7
Cooling Est. Tons Tin Tout GPM
Pumps 60 55 65 100 Use evap pump
Pumps GPM/ea Head whp hp bhp
Boiler 71 12 0.2 55% 0.4
HP Evap 116 120 3.5 65% 5.4
HP Cond 116 25 0.7 65% 1.1
Electric Loads Load Qty BHP hm kW
Heat Pump 1 - - 45.4
Boiler Pump 1 0.5 75% 0.5
HP Evap Pump 1 5.0 92% 4.1
HP Cond Pump 1 1.0 85% 0.9
Total 51
Energy Analysis
Consumption Ground Source Heat Pump Load, kBTU % Load Net, kBTU
1,151,090 80% 920,872
Month % Load kBtu Source Temp COP kBtu kWh
Jan 14% 128,922 32 2.6 49,585 14,533
Feb 11% 101,296 32 2.6 38,960 11,419
Mar 9% 82,879 32 2.6 31,876 9,342
Apr 8% 73,670 34 2.8 26,311 7,711
May 5% 46,044 36 3.0 15,348 4,498
Jun 3% 27,626 38 3.2 8,633 2,530
Jul 3% 27,626 40 3.4 8,125 2,381
Aug 5% 46,044 42 3.5 13,155 3,856
Sep 8% 73,670 40 3.4 21,668 6,350
Oct 9% 82,879 38 3.2 25,900 7,591
Nov 11% 101,296 36 3.0 33,765 9,896
Dec 14%128,922 34 2.8 46,044 13,495
100% 920,872 288% 319,370 93,602
Fuel Oil Boiler Load, kBTU % Load Net, kBTU Efficiency kBTU/gal Fuel, gals
1,151,090 20% 230,218 68% 138.5 2,444
Pumps Unit kW Hours kWh
Boiler Pump 0.5 500 249
Ground Loop 5.0 7,000 35,000
Load 0.9 7,500 6,582
Cooling 2.0 100 200
42,031
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Centennial Hall
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GROUNDWATER WELL HEAT PUMP
Sizing
Heating Plant Load, MBH Factor Size, MBH kWh Tons COP kW
Heat pump 930 70% 651 - 54 3.0 64
B-1 930 76% 704
B-2 930 76% 704 - - - -
221% 2,059 0 54 64
Seawater Heat Exchanger Flow Inlet Outlet Spec Heat
Side gpm °F °F Btu/lb°F MBH Tons
Seawater 163 40.0 34.0 0.90 440 37
Evap 163 32.3 38.0 0.94 -440 -37
Cooling
Tons Tin Tout GPM
Pumps 60 58 68 144
Pumps GPM Head whp hp bhp hm kW
Boiler 71 12 0.2 55% 0.4 75% 0.4
Well 163 50 2.1 55% 3.7 93% 3.0
HP Evap 163 25 1.0 60% 1.7 93% 1.4
HP Cond 163 25 1.0 60% 1.7 92% 1.4
Additional Electric Load
Load Qty BHP hm kW
Heat Pump 1 - - 64
Boiler Pump 1 0.5 75% 0.5
Well pumps 1 5.0 93% 4
Load Pumps 1 2 93% 2
Source Pumps 1 2 92% 2
Total 71
Energy Analysis
Consumption
Seawater Well Heat Pump Load, kBTU % Load Net, kBTU
1,151,090 95% 1,093,536
Month % Load kBtu Source Temp COP kBtu kWh
Jan 14% 153,095 40 3.4 45,028 13,197
Feb 11% 120,289 40 3.4 35,379 10,369
Mar 9% 98,418 40 3.4 28,947 8,484
Apr 8% 87,483 44 3.5 24,995 7,326
May 5% 54,677 47 3.6 15,188 4,451
Jun 3% 32,806 50 3.7 8,867 2,599
Jul 3% 32,806 52 3.8 8,633 2,530
Aug 5% 54,677 54 3.9 14,128 4,141
Sep 8% 87,483 52 3.8 23,022 6,747
Oct 9% 98,418 50 3.7 26,600 7,796
Nov 11% 120,289 47 3.6 33,414 9,793
Dec 14%153,095 44 3.5 43,741 12,820
100% 1,093,536 355% 307,941 90,252
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Centennial Hall
July 7, 2012
Fuel Oil Boiler Load, kBTU % Load Net, kBTU Efficiency kBTU/gal Fuel, gals
1,151,090 5% 57,555 68% 138.5 611
Pumps kW Hours kWh
Boiler Pump 0.4 500 195
Well Pump 3.0 7,500 22,478
Load 1.4 7,500 10,302
Cooling 1.4 80 111
33,085
SEAWATER INTAKE HEAT PUMP
Sizing
Heating Plant Load, MBH Factor Size, MBH kWh Tons COP kW
Heat pump 930 70% 651 - 54 3.0 64
B-1 930 76% 704
B-2 930 76% 704 - - - -
221% 2,059 0 54 64
Seawater Heat Exchanger Flow Inlet Outlet Spec Heat
Side gpm °F °F Btu/lb°F MBH Tons
Seawater 163 38.0 32.0 0.90 440 37
Evap 163 30.3 36.0 0.94 -440 -37
Pumps Pump GPM Head whp hp bhp hm kW
Seawater 163 60 2.5 55% 4.5 93% 3.6
Evap 163 25 1.0 60% 1.7 93% 1.4
Cond 163 25 1.0 60% 1.7 92% 1.4
6.4
Cooling Ex Tons Tin Tout GPM
Pumps 60 55 65 144
Additional Electric Load
Load Qty BHP kW
Heat Pump 1 - 64
Wet well pumps 1 5 4
Load Pumps 1 2 1
Source Pumps 1 2 1
Total 70
AIR SOURCE HEAT PUMP
Sizing HP ERV Fan Coils
Auditorium 2 1 2
West 1 1 11
East 1 1 11
Museum 2 1 6
6 4 30
Additional Electric Load MBH kW
930 273 Backup electric resistance heat
Page 5
Alaska Energy Engineering LLC Conceptual Sizing
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Centennial Hall
July 7, 2012
Energy Analysis
Consumption kBtu
Baseline Heating Load 1,151,090
System Efficiency Gain 10%
Net Load 1,035,981
Month % Load kBtu Backup %Backup, kBtu Ave Temp COP kBtu kWh
Jan 14% 145,037 5% 7,252 33 1.9 73,907 23,786
Feb 11% 113,958 5% 5,698 35 2.0 55,445 17,920
Mar 9% 93,238 5% 4,662 37 2.1 43,079 13,992
Apr 8% 82,879 5% 4,144 40 2.2 35,184 11,526
May 5% 51,799 5% 2,590 46 2.7 18,428 6,160
Jun 3% 31,079 5% 1,554 49 2.9 10,177 3,438
Jul 3% 31,079 5% 1,554 54 3.3 9,057 3,110
Aug 5% 51,799 5% 2,590 55 3.3 14,813 5,100
Sep 8% 82,879 5% 4,144 52 3.1 25,202 8,601
Oct 9% 93,238 5% 4,662 44 2.5 35,164 11,672
Nov 11% 113,958 5% 5,698 39 2.2 49,798 16,265
Dec 14%145,037 5%7,252 32 1.8 79,423 25,403
100% 1,035,981 51,799 449,675 146,974
219%
kBtu
Cooling Load 155,397
Month % Load kBtu Ave Temp COP kBtu kWh
Jun 20% 31,079 49 4.0 7,813 2,290
Jul 40% 62,159 54 3.9 15,810 4,634
Aug 40%62,159 55 3.9 15,846 4,644
100% 155,397 39,469 11,568
394%
Page 6
Alaska Energy Engineering LLC Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 alaskaenergy@earthlink.net
Harrigan Centennial Hall Renewable Energy Feasibility Study
Baseline HVAC System
Basis
Economic Factors Energy Inflation
Study Period (years) 30 Fuel Oil 6.6%
Nominal Discount Rate 5.5% Electricity, Yrs 1-2 9.0%
General Inflation 2.90% Electricity, Yrs 3-30 2.5%
Real Discount Rate 2.5%
Construction Costs Qty Unit Base Cost Year 0 Cost
Architectural
Mechanical Space 722 sqft $250.00 $180,500
Heating Plant
Refurbish existing boilers 2 ea $1,500.00 $3,000
Secondary loop including pumps, VFDs, and appurtenances 1 ls $30,000.00 $30,000
Hydronic Heating System
Insulated hydronic piping (3/4" to 3"), supports, seismic 2,320 lnft $42.00 97,440
AHU / MAF heating coils 4 ea $4,000.00 16,000
Unit heaters 4 ea $1,250.00 5,000
Cabinet unit heaters 2 ea $1,500.00 3,000
Terminal box reheat coil and valves 24 ea $750.00 18,000
Ventilation Systems
AHU-1: Auditorium 7,200 cfm $5.00 36,000
Ductwork 1,700 lbs $9.00 15,300
AHU-2: Meetings/Offices 14,500 cfm $4.50 65,250
Ductwork 4,300 lbs $9.00 38,700
AHU-3: Museum 8,700 cfm $5.00 43,500
Ductwork 2,000 lbs $9.00 18,000
MAF-1: Kitchen 2,000 cfm $5.50 11,000
Ductwork 500 lbs $9.00 4,500
VAV boxes 24 ea $675.00 16,200
Grilles and diffusers 140 ea $137.00 19,180
Sound attenuators 4 lot $8,000.00 32,000
Outside air louver and damper 70 sqft $57.00 3,990
Miscellaneous dampers, etc. 1 lot $4,000.00 4,000
Cooling System
Air-cooled DX cooling system 3 ea $20,000.00 $60,000
DX coils, piping and appurtenances 3 ea $7,500.00 $22,500
Condenser unit mounting and screen 3 ea $5,000.00 $15,000
DDC Controls
Heating and cooling 150 pts $1,600.00 $240,000
Electrical
Electrical, 3-phase power 7 ls $7,500.00 $52,500
Electrical, 1-phase power 8 ls $1,500.00 $12,000
Contingencies
Design contingency 20% $212,512.00
General Overhead & Profit 30% $382,521.60
Design fees 10% $165,759.36
Owner's project costs 8% $145,868.24
Total Construction Costs $1,970,000
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Page 7
Alaska Energy Engineering LLC Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 alaskaenergy@earthlink.net
Harrigan Centennial Hall Renewable Energy Feasibility Study
Baseline HVAC System
July 7, 2012
Maintenance Costs Years Qty Unit Base Cost Present Value
Boiler Maintenance
Monthly: 1 hours per month each 1 - 30 24 hrs $60.00 $29,292
Annual: 8 hours, 2x per year, each 1 - 30 32 hrs $60.00 $39,056
Parts Allowance 1 - 30 2 LS $250.00 $10,171
A/C condenser unit maintenance
Daily: 5 minutes per day 1 - 30 8 hrs $60.00 $9,154
Monthly: 30 minutes per month, ea 1 - 30 5 hrs $60.00 $5,492
Annual: 8 hours per year 1 - 30 24 hrs $110.00 $53,703
Contracted Tune-up: Every Five Years 5 - 5 1 ls $2,500.00 $2,152
Contracted Tune-up: Every Five Years 10 - 10 1 ls $2,500.00 $1,900
Contracted Tune-up: Every Five Years 15 - 15 1 ls $2,500.00 $1,677
Contracted Tune-up: Every Five Years 20 20 1 ls $2,500.00 $1,480
Contracted Tune-up: Every Five Years 25 25 1 ls $2,500.00 $1,307
Parts Allowance 1 - 30 1 LS $300.00 $6,103
Pump maintenance 1 - 30 4 ea $200.00 $16,685
AHU maintenance, 4 hours, ea 1 - 30 16 hrs $60.00 $20,022
A/C unit replacement 18 -18 1 LS $48,000.00 $29,877
Boiler replacement 22 - 22 2 LS $18,000.00 $20,279
Total Annual Costs $250,000
Energy Costs Years Qty Unit Base Cost Present Value
Fuel Oil 1 - 30 12,200 gals $4.01 $1,729,811
Electricity, Years 1-2 1 - 2 24,761 kWh $0.109 $5,670
Electricity, Years 3-30 3 - 30 24,761 kWh $0.13 $56,333
Total Energy Costs $1,790,000
$4,010,000Present Worth
Page 8
Alaska Energy Engineering LLC Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 alaskaenergy@earthlink.net
Harrigan Centennial Hall Renewable Energy Feasibility Study
Ground Source Heat Pump System
Basis
Economic Factors Energy Inflation
Study Period (years) 30 Fuel Oil 6.6%
Nominal Discount Rate 5.5% Electricity, Yrs 1-2 9.0%
General Inflation 2.90% Electricity, Yrs 3-30 2.5%
Real Discount Rate 2.5%
Construction Costs Qty Unit Base Cost Year 0 Cost
Architectural
Mechanical Space 800 ea $250 $200,000
Loopfield
Thermal conductivity test
Borehole, backfill, with 1" HDPE pipe loop 325 lnft $50 $16,250
Thermal conductivity test kit rental and data analysis 1 ls $2,500 $2,500
Test labor 20 hrs $120 $2,400
Generator rental 1 ls $600 $600
Loopfield: Mob/Demob from Juneau 1 ls $25,000 $25,000
Loopfield: Boreholes, pipe loop, backfill, horizontal piping 9,363 lnft $36 $337,068
Loopfield header and piping in building 1 ls $25,000 $25,000
Heating Plant
Refurbish existing boilers 2 ea $1,500 $3,000
Heat Pump
465 MBH water-to-water heat pump 1 ls $90,000 $90,000
Evaporator pump, 5 HP with VFD, and primary piping, appurt 1 ea $15,000 $15,000
Condenser pump, 1 HP, piping, and appurtenances 1 ea $7,000 $7,000
Heating tank, 300 gallons 1 ls $10,000 $10,000
Secondary loop including pumps, VFDs, and appurtenances 1 ls $30,000 $30,000
Hydronic Heating System
Insulated hydronic piping (3/4" to 4"), supports, seismic 2,320 lnft $48 111,360
AHU / MAF heating coils 4 ea $6,000 24,000
Unit heaters 4 ea $1,750 7,000
Cabinet unit heaters 2 ea $2,000 4,000
Terminal box reheat coil and valves 24 ea $1,000 24,000
Ventilation Systems
AHU-1: Auditorium 7,200 cfm 5.25 37,800
Ductwork 1,700 lbs 9.00 15,300
AHU-2: Meetings/Offices 14,500 cfm 4.75 68,875
Ductwork 4,300 lbs 9.00 38,700
AHU-3: Museum 8,700 cfm 5.25 45,675
Ductwork 2,000 lbs 9.00 18,000
MAF-1: Kitchen 2,000 cfm 5.50 11,000
Ductwork 500 lbs 9.00 4,500
VAV boxes 24 ea 675.00 16,200
Grilles and diffusers 140 ea 137.00 19,180
Sound attenuators 4 lot 8,000.00 32,000
Outside air louver and damper 70 sqft 57.00 3,990
Miscellaneous dampers, etc. 1 lot 4,000.00 4,000
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July 7, 2012
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Page 9
Alaska Energy Engineering LLC Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 alaskaenergy@earthlink.net
Harrigan Centennial Hall Renewable Energy Feasibility Study
Ground Source Heat Pump System
July 7, 2012
Construction Costs Qty Unit Base Cost Year 0 Cost
Cooling System
Controls to integrate with hydronic heating system; 2-pipe system 4 pts $1,600 $6,400
DDC Controls
Heating and cooling 150 pts $1,600 $240,000
Electrical
Increase electric service, 50 kW 1 ls $20,000 $20,000
Electrical, 3-phase power 10 ls $7,500 $75,000
Electrical, 1-phase power 8 ls $7,500 $60,000
Contingencies
Design contingency 20% $330,159.60
General Overhead & Profit 30% $594,287.28
Design fees 10% $257,524.49
Owner's project costs 8% $226,621.55
Total Construction Costs $3,060,000
Maintenance Costs Years Qty Unit Base Cost Present Value
Maintenance and Repair
Boiler Maintenance
Monthly: 1 hours per month 1 - 30 12 hrs $60.00 $14,646
Annual: 8 hours, 1x per year 1 - 30 16 hrs $60.00 $19,528
Parts Allowance 1 - 30 2 LS $250.00 $10,171
Heat Pump
Daily: 5 minutes per day 1 - 30 30 hrs $60.00 $37,124
Monthly: 30 minutes per month 1 - 30 6 hrs $60.00 $7,323
Every Three Months: 30 minutes each 1 - 30 2 hrs $110.00 $4,475
Annual: 8 hours per year 1 - 30 8 hrs $110.00 $17,901
Contracted Tune-up: Every Five Years 5 - 5 1 ls $1,500.00 $1,291
Contracted Tune-up: Every Five Years 10 - 10 1 ls $1,500.00 $1,140
Contracted Tune-up: Every Five Years 15 - 15 1 ls $1,500.00 $1,006
Contracted Tune-up: Every Five Years 20 20 1 ls $1,500.00 $888
Contracted Tune-up: Every Five Years 25 25 1 ls $1,500.00 $784
Parts Allowance 1 - 30 1 LS $250.00 $5,085
Pump maintenance 1 - 30 6 ea $200.00 $25,027
AHU maintenance, 4 hours, ea 1 - 30 16 hrs $60.00 $20,022
Replacement
Heat pump replacement 18 - 18 1 ea $72,000.00 $45,948
Salvage Value
Loopfield (assume 75-year life) 30 - 30 -1 ea $202,240.80 ($95,666)
Total Annual Costs $120,000
Energy Costs Years Qty Unit Base Cost Present Value
Fuel Oil 1 - 30 2,444 gals $4.01 $346,593
Electricity, Years 1-2 1 - 2 135,633 kWh $0.109 $31,056
Electricity, Years 3-30 3 - 30 135,633 kWh $0.13 $308,571
Total Energy Costs $690,000
$3,870,000
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Page 10
Alaska Energy Engineering LLC Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 alaskaenergy@earthlink.net
Harrigan Centennial Hall Renewable Energy Feasibility Study
Groundwater Well Heat Pump System
Basis
Economic Factors Energy Inflation
Study Period (years) 30 Fuel Oil 6.6%
Nominal Discount Rate 5.5% Electricity, Yrs 1-2 9.0%
General Inflation 2.90% Electricity, Yrs 3-30 2.5%
Real Discount Rate 2.5%
Construction Costs Qty Unit Base Cost Year 0 Cost
Architectural
Mechanical Space 800 ea $250.00 $200,000
Seawater Well
Mobilization 1 ea $15,000.00 $15,000
Intake
Pipe Casing 1 ea $7,000.00 $7,000
Installation of Pipe Casing 1 ea 8,000.00 $8,000
Clean out Pipe Casing 1 ea 2,000.00 $2,000
Contingency for Rock Drilling 1 ls 15,000.00 $15,000
Well House - 10'x12' 120 sqft 200.00 $24,000
Turbine Pumps 1 ea 10,000.00 $10,000
Outlet
Trenching and Backfill for Pipeline 100 cy $20.00 $2,000
Pipeline 100 lf 20.00 $2,000
Pig ports and appurtenances 1 ls 65,000.00 $65,000
Anchors for Pipeline 3 ea 3,500.00 $10,500
Control Manhole 1 ls 8,000.00 $8,000
Outlet Screen Box and Base 1 ea 7,500.00 $7,500
Seawater piping in building 1 ls 12,000.00 $12,000
Seawater heat exchanger and appurtenances, titanium 1 ls 65,000.00 $65,000
Discharge permits 1 ls 20,000.00 $20,000
Heating Plant
Refurbish existing boilers 2 ea $1,500.00 $3,000
Heat Pump
650 MBH water-to-water heat pump 1 ls $110,000.00 $110,000
Evaporator pump, 2 HP with VFD, and primary piping, appurt 1 ea 12,500.00 $12,500
Condenser pump, 2 HP, piping, and appurtenances 1 ea 5,000.00 $5,000
Heating tank, 300 gallons 1 ls $10,000.00 $10,000
Secondary loop including pumps, VFDs, and appurtenances 1 ls 30,000.00 $30,000
Hydronic Heating System
Insulated hydronic piping (3/4" to 4"), supports, seismic 2,320 lnft 48.00 111,360
AHU / MAF heating coils 4 ea 6,000.00 24,000
Unit heaters 4 ea 1,750.00 7,000
Cabinet unit heaters 2 ea 2,000.00 4,000
Terminal box reheat coil and valves 24 ea 1,000.00 24,000
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July 7, 2012
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Page 11
Alaska Energy Engineering LLC Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 alaskaenergy@earthlink.net
Harrigan Centennial Hall Renewable Energy Feasibility Study
Groundwater Well Heat Pump System
July 7, 2012
Construction Costs Qty Unit Base Cost Year 0 Cost
Ventilation Systems
AHU-1: Auditorium 7,200 cfm 5.25 37,800
Ductwork 1,700 lbs 9.00 15,300
AHU-2: Meetings/Offices 14,500 cfm 4.75 68,875
Ductwork 4,300 lbs 9.00 38,700
AHU-3: Museum 8,700 cfm 5.25 45,675
Ductwork 2,000 lbs 9.00 18,000
MAF-1: Kitchen 2,000 cfm 5.50 11,000
Ductwork 500 lbs 9.00 4,500
VAV boxes 24 ea 675.00 16,200
Grilles and diffusers 140 ea 137.00 19,180
Sound attenuators 4 lot 8,000.00 32,000
Outside air louver and damper 70 sqft 57.00 3,990
Miscellaneous dampers, etc. 1 lot 4,000.00 4,000
Cooling System
Controls to integrate with hydronic heating system; 2-pipe system 4 pts 1,600.00 $6,400
DDC Controls
Heating and cooling 150 pts $1,600.00 $240,000
Electrical
Increase electric service, 70 kW 1 ls 25,000 $25,000
Electrical, 3-phase power 10 ls 7,500 $75,000
Electrical, 1-phase power 8 ls 7,500 $60,000
Contingencies
Design contingency 20% $307,096.00
General Overhead & Profit 30% $552,772.80
Design fees 10% $239,534.88
Permitting 1 ls $6,000 $6,000
Owner's project costs 8% $211,270.69
Total Construction Costs $2,850,000
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Page 12
Alaska Energy Engineering LLC Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 alaskaenergy@earthlink.net
Harrigan Centennial Hall Renewable Energy Feasibility Study
Groundwater Well Heat Pump System
July 7, 2012
Maintenance Costs Years Qty Unit Base Cost Present Value
Maintenance and Repair
Boiler Maintenance
Monthly: 1 hours per month 1 - 30 12 hrs $60.00 $14,646
Annual: 8 hours, 1x per year 1 - 30 16 hrs $60.00 $19,528
Parts Allowance 1 - 30 2 LS $250.00 $10,171
Heat Pump
Daily: 5 minutes per day 1 - 30 30 hrs $60.00 $37,124
Monthly: 30 minutes per month 1 - 30 6 hrs $60.00 $7,323
Every Three Months: 30 minutes each 1 - 30 2 hrs $110.00 $4,475
Annual: 8 hours per year 1 - 30 8 hrs $110.00 $17,901
Contracted Tune-up: Every Five Years 5 - 5 1 ls $1,500.00 $1,291
Contracted Tune-up: Every Five Years 10 - 10 1 ls $1,500.00 $1,140
Contracted Tune-up: Every Five Years 15 - 15 1 ls $1,500.00 $1,006
Contracted Tune-up: Every Five Years 20 20 1 ls $1,500.00 $888
Contracted Tune-up: Every Five Years 25 25 1 ls $1,500.00 $784
Parts Allowance 1 - 30 1 LS $250.00 $5,085
AHU maintenance, 4 hours, ea 1 - 30 16 hrs $60.00 $20,022
Seawater System Maintenance
Turbine pump maintenance 1 - 30 2 ea $300.00 $12,514
Pipeline cleaning 1 - 30 1 ea $1,000.00 $20,856
Heat exchanger cleaning 1 - 30 4 hrs $60.00 $5,005
Pump maintenance 1 - 30 4 ea $200.00 $16,685
Replacement
Heat pump replacement 18 - 18 1 ea $88,000.00 $56,158
Total Annual Costs $250,000
Energy Costs Years Qty Unit Base Cost Present Value
Fuel Oil 1 - 30 611 gals $4.01 $86,648
Electricity, Years 1-2 1 - 2 123,338 kWh $0.109 $28,240
Electricity, Years 3-30 3 - 30 123,338 kWh $0.13 $280,599
Total Energy Costs $400,000
$3,500,000Present Worth
Page 13
Alaska Energy Engineering LLC Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 alaskaenergy@earthlink.net
Harrigan Centennial Hall Renewable Energy Feasibility Study
Seawater Intake Heat Pump System
Basis
Economic Factors Energy Inflation
Study Period (years) 30 Fuel Oil 6.6%
Nominal Discount Rate 5.5% Electricity, Yrs 1-2 9.0%
General Inflation 2.90% Electricity, Yrs 3-30 2.5%
Real Discount Rate 2.5%
Construction Costs Qty Unit Base Cost Year 0 Cost
Architectural
Mechanical Space 800 ea $250.00 $200,000
Seawater Well
Mobilization 1 ea $66,000.00 $66,000
Intake
Shoring Materials 1 ea $115,000.00 $115,000
Shoring Installation 2 ea 20,000.00 $40,000
Dewatering for Excavation and Wet Well Construction 1 ea 25,000.00 $25,000
Excavation 320 cy 15.00 $4,800
Contingency for Rock Excavation 1 ls 10,000.00 $10,000
Wet Well Base 1 ea 4,000.00 $4,000
Wet Well - 6' Dia x 27 Feet High 1 ea 12,000.00 $12,000
Backfill and Compact Wet Wells 300 CY 20.00 $6,000
Well House Slab 24' x 12' x 8" 7.5 CY 1,000.00 $7,500
Trenching and Backfill for Pipelines 320 CY 30.00 $9,600
Contingency for Rock Excavation 1 LS 15,000.00 $15,000
Intake Pipelines 130 LF 25.00 $3,250
Pig ports and appurtenances 1 ls 75,000.00 $75,000
Intake Box and Base 1 Each 7,500.00 $7,500
Intake Pipeline Anchors 6 Each 3,500.00 $21,000
Well House - 12' x 24' (cost without slab) 288 SF 170.00 $48,960
Turbine Pumps 1 Each 10,000.00 $10,000
Outlet
Trenching and Backfill for Pipeline 100 cy $20.00 $2,000
Pipeline 100 lf 20.00 $2,000
Anchors for Pipeline 3 ea 3,500.00 $10,500
Pig ports and appurtenances 1 ls 75,000.00 $75,000
Control Manhole 1 ls 8,000.00 $8,000
Outlet Screen Box and Base 1 ea 7,500.00 $7,500
Seawater piping in building 1 ls 12,000.00 $12,000
Seawater heat exchanger and appurtenances, titanium 1 ls 75,000.00 $75,000
Discharge permit 1 ls 30,000.00 $30,000
Heating Plant
Refurbish existing boilers 2 ea $1,500.00 $3,000
Heat Pump
650 MBH water-to-water heat pump 1 ls $110,000.00 $110,000
Evaporator pump, 2 HP with VFD, and primary piping, appurt 1 ea 12,500.00 $12,500
Condenser pump, 2 HP, piping, and appurtenances 1 ea 5,000.00 $5,000
Heating tank, 300 gallons 1 ls $10,000.00 $10,000
Secondary loop including pumps, VFDs, and appurtenances 1 ls 30,000.00 $30,000
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Page 14
Alaska Energy Engineering LLC Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 alaskaenergy@earthlink.net
Harrigan Centennial Hall Renewable Energy Feasibility Study
Seawater Intake Heat Pump System
July 7, 2012
Construction Costs Qty Unit Base Cost Year 0 Cost
Hydronic Heating System
Insulated hydronic piping (3/4" to 4"), supports, seismic 2,320 lnft 48.00 111,360
AHU / MAF heating coils 4 ea 6,000.00 24,000
Unit heaters 4 ea 1,750.00 7,000
Cabinet unit heaters 2 ea 2,000.00 4,000
Terminal box reheat coil and valves 24 ea 1,000.00 24,000
Ventilation Systems
AHU-1: Auditorium 7,200 cfm 5.25 37,800
Ductwork 1,700 lbs 9.00 15,300
AHU-2: Meetings/Offices 14,500 cfm 4.75 68,875
Ductwork 4,300 lbs 9.00 38,700
AHU-3: Museum 8,700 cfm 5.25 45,675
Ductwork 2,000 lbs 9.00 18,000
MAF-1: Kitchen 2,000 cfm 5.50 11,000
Ductwork 500 lbs 9.00 4,500
VAV boxes 24 ea 675.00 16,200
Grilles and diffusers 140 ea 137.00 19,180
Sound attenuators 4 lot 8,000.00 32,000
Outside air louver and damper 70 sqft 57.00 3,990
Miscellaneous dampers, etc. 1 lot 4,000.00 4,000
Cooling System
Controls to integrate with hydronic heating system; 2-pipe system 4 pts 1,600.00 $6,400
DDC Controls
Heating and cooling 150 pts $1,600.00 $240,000
Electrical
Increase electric service, 70 kW 1 ls 25,000 $25,000
Electrical, 3-phase power 10 ls 7,500 $75,000
Electrical, 1-phase power 8 ls 7,500 $60,000
Contingencies
Design contingency 20% $393,018.00
General Overhead & Profit 30% $707,432.40
Design fees 10% $306,554.04
Permitting 1 ls $10,000 $10,000
Owner's project costs 8% $270,567.56
Total Construction Costs $3,650,000
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Page 15
Alaska Energy Engineering LLC Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 alaskaenergy@earthlink.net
Harrigan Centennial Hall Renewable Energy Feasibility Study
Seawater Intake Heat Pump System
July 7, 2012
Maintenance Costs Years Qty Unit Base Cost Present Value
Maintenance and Repair
Boiler Maintenance
Monthly: 1 hours per month 1 - 30 12 hrs $60.00 $14,646
Annual: 8 hours, 1x per year 1 - 30 16 hrs $60.00 $19,528
Parts Allowance 1 - 30 2 LS $250.00 $10,171
Heat Pump
Daily: 5 minutes per day 1 - 30 30 hrs $60.00 $37,124
Monthly: 30 minutes per month 1 - 30 6 hrs $60.00 $7,323
Every Three Months: 30 minutes each 1 - 30 2 hrs $110.00 $4,475
Annual: 8 hours per year 1 - 30 8 hrs $110.00 $17,901
Contracted Tune-up: Every Five Years 5 - 5 1 ls $1,500.00 $1,291
Contracted Tune-up: Every Five Years 10 - 10 1 ls $1,500.00 $1,140
Contracted Tune-up: Every Five Years 15 - 15 1 ls $1,500.00 $1,006
Contracted Tune-up: Every Five Years 20 20 1 ls $1,500.00 $888
Contracted Tune-up: Every Five Years 25 25 1 ls $1,500.00 $784
Parts Allowance 1 - 30 1 LS $250.00 $5,085
AHU maintenance, 4 hours, ea 1 - 30 16 hrs $60.00 $20,022
Seawater System Maintenance
Turbine pump maintenance 1 - 30 2 ea $300.00 $12,514
Pipeline cleaning 1 - 30 1 ea $1,500.00 $31,284
Heat exchanger cleaning 1 - 30 4 hrs $60.00 $5,005
Pump maintenance 1 - 30 4 ea $200.00 $16,685
Replacement
Heat pump replacement 18 - 18 1 ea $88,000.00 $56,158
Total Annual Costs $260,000
Energy Costs Years Qty Unit Base Cost Present Value
Fuel Oil 1 - 30 611 gals $4.01 $86,648
Electricity, Years 1-2 1 - 2 123,338 kWh $0.109 $28,240
Electricity, Years 3-30 3 - 30 123,338 kWh $0.13 $280,599
Total Energy Costs $400,000
$4,310,000Present Worth
Page 16
Alaska Energy Engineering LLC Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 alaskaenergy@earthlink.net
Harrigan Centennial Hall Renewable Energy Feasibility Study
Air-source Heat Pump System
Basis
Economic Factors Energy Inflation
Study Period (years) 30 Fuel Oil 6.6%
Nominal Discount Rate 5.5% Electricity, Yrs 1-2 9.0%
General Inflation 2.90% Electricity, Yrs 3-30 2.5%
Real Discount Rate 2.5%
Construction Costs Qty Unit Base Cost Year 0 Cost
Architectural
Mechanical Space 800 ea $250 $200,000
Convert former fluid cooler room to heat pump room 1 ls $5,000 $5,000
Heating Plant
Demolish fuel oil boilers and appurtenances 1 ea $8,000 $8,000
Demolish fuel oil system 1 ea $3,000 $3,000
Outdoor Units
Outdoor heat pump unit
Material 6 ea $8,000 $48,000
Installation 6 ea $2,000 $12,000
Discharge ductwork 6 ea $2,500 $15,000
Electrical service 6 ea $2,500 $15,000
Controlled mixing boxes
Material 6 ea $5,800 $34,800
Installation 6 ea $500 $3,000
Connections 28 ea $200 $5,600
Piping from outdoor units 6 ea $15,500 $93,000
Valves 48 ea $55 $2,640
Energy Recovery Ventilators
Intake louver and ductwork 4 ea $2,500 $10,000
Discharge louver and ductwork 4 ea $2,500 $10,000
Energy recovery ventilator
Material 5 ea $14,000 $70,000
Installation 5 ea $2,500 $12,500
Supply ductwork to terminal units 700 lnft $75 $52,500
Exhaust ductwork and grilles 350 lnft $75 $26,250
Electrical service 5 ea $7,500 $37,500
0
0
0
0
0
0
0
0
July 7, 2012
Year
0
0
0
0
0
0
0
0
0
0
0
0
Page 17
Alaska Energy Engineering LLC Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 alaskaenergy@earthlink.net
Harrigan Centennial Hall Renewable Energy Feasibility Study
Air-source Heat Pump System
July 7, 2012
Construction Costs Qty Unit Base Cost Year 0 Cost
Terminal Units
Duct mounted fan coil units
Material 25 ea $1,750 $43,750
Installation 25 ea $500 $12,500
Piping from controlled mixing box 25 ea $1,000 $25,000
Supply ductwork to diffusers 25 ea $1,500 $37,500
Return ductwork from grilles 25 ea $750 $18,750
Electric service 25 ea $1,500 $37,500
Wall-mounted fan coils
Material 5 ea $1,000 $5,000
Installation 5 ea $250 $1,250
Piping from controlled mixing box 5 ea $450 $2,250
Electric service 5 ea $3,500 $17,500
Piping to auditorium fan coils 200 lnft $30 $6,000
Piping to ERV coils 150 lnft $30 $4,500
ERV heating coils 5 ea $1,000 $5,000
Sound traps 5 ea $6,000 $30,000
Thermostats 28 ea $170 $4,760
Electrical
Larger electric service and distribution, 275 kW 1 ls 75,000 $75,000
Controls
Material 1 LS $50,000 $50,000
Installation 1 LS $150,000 $150,000
Contingencies
Design contingency 15% $178,507.50
General Overhead & Profit 30% $410,567.25
Design fees 10% $177,912.48
Owner's project costs 8% $156,562.98
Total Construction Costs $2,110,000
Year
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
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Page 18
Alaska Energy Engineering LLC Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 alaskaenergy@earthlink.net
Harrigan Centennial Hall Renewable Energy Feasibility Study
Air-source Heat Pump System
July 7, 2012
Maintenance Costs Years Qty Unit Base Cost Present Value
Heat Pump Maintenance
Daily: 30 minutes per day 1 - 30 183 hrs $60.00 $222,744
Monthly: 8 hours per month 1 - 30 96 hrs $60.00 $117,169
Every Three Months: 8 hours 1 - 30 32 hrs $110.00 $71,604
Annual: 16 hours per year 1 - 30 16 hrs $110.00 $35,802
Parts Allowance 1 - 30 1 LS $500.00 $10,171
Fan coils
Filter replacement 1 - 30 25 ea $150.00 $78,210
Maintenance 1 - 30 25 ea $60.00 $31,284
Energy Recovery Ventilators
Filter replacement 1 - 30 5 ea $300.00 $31,284
Maintenance
Daily, 0.25 hours per day 1 - 30 65 hrs $60.00 $81,338
Annual: 1 day 1 - 30 8 hrs $60.00 $10,011
Replacement
Outdoor units 12 - 12 6 ea $9,000.00 $40,027
Outdoor units 24 - 24 6 ea $9,000.00 $29,669
Energy recovery ventilators 20 - 20 5 ea $15,250.00 $46,291
Fan coil units 20 - 20 25 ea $2,000.00 $30,355
Total Annual Costs $840,000
Energy Costs Years Qty Unit Base Cost Present Value
Fuel Oil 1 - 30 0 gals $4.01 $0
Electricity, Years 1-2 1 - 2 158,541 kWh $0.109 $36,301
Electricity, Years 3-30 3 - 30 158,541 kWh $0.13 $360,689
Total Energy Costs $400,000
$3,350,000Present Worth
Page 19
Alaska Energy Engineering LLC
Appendix C
Library Conceptual Diagrams
Alaska Energy Engineering LLC
Blank Page
Alaska Energy Engineering LLC25200 Amalga Harbor RoadJuneau, Alaska 99801Phone and Fax: (907) 789-1226E-mail: jim@alaskaenergy.us
Alaska Energy Engineering LLC25200 Amalga Harbor RoadJuneau, Alaska 99801Phone and Fax: (907) 789-1226E-mail: jim@alaskaenergy.us
Alaska Energy Engineering LLC25200 Amalga Harbor RoadJuneau, Alaska 99801Phone and Fax: (907) 789-1226E-mail: jim@alaskaenergy.us
Alaska Energy Engineering LLC25200 Amalga Harbor RoadJuneau, Alaska 99801Phone and Fax: (907) 789-1226E-mail: jim@alaskaenergy.us
Alaska Energy Engineering LLC25200 Amalga Harbor RoadJuneau, Alaska 99801Phone and Fax: (907) 789-1226E-mail: jim@alaskaenergy.us
Alaska Energy Engineering LLC
Appendix D
Library Sizing and Life Cycle Cost Calculations
Alaska Energy Engineering LLC
Blank Page
Alaska Energy Engineering LLC Summary
25200 Amalga Harbor Road Tel/Fax: 907-789-1226
Juneau, Alaska 99801 alaskaenergy@earthlink.net
Kettleson Memorial Library Renewable Energy Feasibility Study
Existing Library Heating System Optimization Analysis
Baseline Economic Factors
Economic Factors Energy Inflation
Study Period (years) 30 Fuel Oil 6.6%
Nominal Discount Rate 5.5% Electricity, Yrs 1-2 9.0%
General Inflation 2.90% Electricity, Yrs 3-30 2.5%
Base Case: 6.6% Fuel Oil, 2.5% Electricity Construction Maintenance Energy Total
Baseline Fuel Oil Boilers - Existing Building $0 $109,000 $568,000 $677,000
Ground Source Heat Pump System - Existing Building $488,000 $107,000 $217,000 $812,000
Seawater Heat Pump System - Existing Building $466,000 $160,000 $136,000 $762,000
Air Source Heat Pump System - Existing Building $390,000 $231,000 $159,000 $780,000
High Fuel Oil Case: 8% Fuel Oil, 2.5% Electricity Construction Maintenance Energy Total
Baseline Fuel Oil Boilers - Existing Building $0 $109,000 $707,000 $816,000
Ground Source Heat Pump System - Existing Building $488,000 $107,000 $245,000 $840,000
Seawater Heat Pump System - Existing Building $466,000 $160,000 $143,000 $769,000
Air Source Heat Pump System - Existing Building $390,000 $231,000 $166,000 $787,000
Low Fuel Oil Case: 4.8% Fuel Oil, 2.5% Electricity Construction Maintenance Energy Total
Baseline Fuel Oil Boilers - Existing Building $0 $109,000 $436,000 $545,000
Ground Source Heat Pump System - Existing Building $488,000 $107,000 $191,000 $786,000
Seawater Heat Pump System - Existing Building $466,000 $160,000 $130,000 $756,000
Air Source Heat Pump System - Existing Building $390,000 $231,000 $152,000 $773,000
High Electricity Case: 6.6% Fuel Oil, 4% Electricity Construction Maintenance Energy Total
Baseline Fuel Oil Boilers - Existing Building $0 $109,000 $569,000 $678,000
Ground Source Heat Pump System - Existing Building $488,000 $107,000 $237,000 $832,000
Seawater Heat Pump System - Existing Building $466,000 $160,000 $157,000 $783,000
Air Source Heat Pump System - Existing Building $390,000 $231,000 $184,000 $805,000
Low Electricity Case: 6.6% Fuel Oil, 1% Electricity Construction Maintenance Energy Total
Baseline Fuel Oil Boilers - Existing Building $0 $109,000 $568,000 $677,000
Ground Source Heat Pump System - Existing Building $488,000 $107,000 $202,000 $797,000
Seawater Heat Pump System - Existing Building $466,000 $160,000 $120,000 $746,000
Air Source Heat Pump System - Existing Building $390,000 $231,000 $140,000 $761,000
June 27, 2012
Present Worth
Page 1
Alaska Energy Engineering LLC Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 alaskaenergy@earthlink.net
Kettleson Memorial Library Renewable Energy Feasibility Study
Baseline Fuel Oil Boilers -Existing Building
Basis
Economic Factors Energy Inflation
Study Period (years) 30 Fuel Oil 6.6%
Nominal Discount Rate 5.5% Electricity, Yrs 1-2 9.0%
General Inflation 2.90% Electricity, Yrs 3-30 2.5%
Real Discount Rate 2.5%
Construction Costs Qty Unit Base Cost Year 0 Cost
None
Contingencies
Design contingency 15% $0.00
General Overhead & Profit 30% $0.00
Design fees 10% $0.00
Owner's project costs 8% $0.00
Total Construction Costs $0
Maintenance Costs Years Qty Unit Base Cost Present Value
Maintenance and Repair
Boiler Maintenance
Daily: 5 minutes per day 1 - 30 30 hrs $60.00 $37,124
Monthly: 2 hours per month 1 - 30 24 hrs $60.00 $29,292
Annual: 8 hours, 2x per year 1 - 30 16 hrs $60.00 $19,528
Parts Allowance 1 - 30 1 LS $150.00 $3,051
AHU maintenance, 4 hours, ea 1 - 30 8 hrs 60.00 $10,011
Filters 1 - 30 2 ea 150.00 $6,257
Pump maintenance 1 - 30 1 ea 200.00 $4,171
Total Annual Costs $109,000
Energy Costs Years Qty Unit Base Cost Present Value
Fuel Oil 1 - 30 4,000 gals $4.01 $567,151
Electricity, Years 1-2 1 - 2 480 kWh $0.109 $110
Electricity, Years 3-30 3 - 30 480 kWh $0.13 $1,092
Total Energy Costs $568,000
$677,000
June 27, 2012
Year
Present Worth
0
0
0
0
Page 2
Alaska Energy Engineering LLC Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 alaskaenergy@earthlink.net
Kettleson Memorial Library Renewable Energy Feasibility Study
Ground Source Heat Pump System -Existing Building
Basis
Economic Factors Energy Inflation
Study Period (years) 30 Fuel Oil 6.6%
Nominal Discount Rate 5.5% Electricity, Yrs 1-2 9.0%
General Inflation 2.90% Electricity, Yrs 3-30 2.5%
Real Discount Rate 2.5%
Construction Costs Qty Unit Base Cost Year 0 Cost
Building Costs
Additional mechanical space 125 sqft 450.00 $56,250
Loopfield
Loopfield: Boreholes, pipe loop, backfill, horizontal piping 2,938 lnft 36.00 $105,750
Loopfield header and piping in building 1 ls 8,000.00 $8,000
Heating System
141 MBH water-to-water heat pump 1 ls $30,000 $30,000
Evaporator pump, 2 HP with VFD 1 ea 6,000.00 $6,000
Condenser pump, 0.5 HP 1 ea 1,500.00 $1,500
Heating tank, 150 gallons 1 ls $6,000.00 $6,000
Connect fuel oil boilers to tank 1 ls $2,500.00 $2,500
Connect building hydronic loop to tank 1 ls $2,500.00 $2,500
Distribution
Replace AHU heating coils 2 ea $3,000.00 $6,000
Replace reheat coils 4 ea $750.00 $3,000
DDC Controls
Heating 12 pts $2,000.00 $24,000
Electrical
Electrical, 3-phase power 3 ls 3,500 $10,500
Electrical, 1-phase power 1 ls 1,500 $1,500
Contingencies
Design contingency 20% $52,700.00
General Overhead & Profit 30% $94,860.00
Design fees 10% $41,106.00
Owner's project costs 8% $36,173.28
Total Construction Costs $488,000
0
0
0
0
0
0
0
0
0
0
0
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June 27, 2012
Year
0
0
0
0
0
0
Page 3
Alaska Energy Engineering LLC Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 alaskaenergy@earthlink.net
Kettleson Memorial Library Renewable Energy Feasibility Study
Ground Source Heat Pump System -Existing Building
June 27, 2012
Maintenance Costs Years Qty Unit Base Cost Present Value
Maintenance and Repair
Heat Pump
Daily: 5 minutes per day 1 - 30 30 hrs $60.00 $37,124
Monthly: 30 minutes per month 1 - 30 6 hrs $60.00 $7,323
Every Three Months: 30 minutes each 1 - 30 2 hrs $60.00 $2,441
Annual: 8 hours per year 1 - 30 8 hrs $60.00 $9,764
Contracted Tune-up: Every Five Years 5 - 5 1 ls $1,500.00 $1,291
Contracted Tune-up: Every Five Years 10 - 10 1 ls $1,500.00 $1,140
Contracted Tune-up: Every Five Years 15 - 15 1 ls $1,500.00 $1,006
Contracted Tune-up: Every Five Years 20 20 1 ls $1,500.00 $888
Contracted Tune-up: Every Five Years 25 25 1 ls $1,500.00 $784
Parts Allowance 1 - 30 1 LS $200.00 $4,068
Boiler Maintenance
Monthly: 1 hours per month 1 - 30 12 hrs $60.00 $14,646
Annual: 8 hours, 1x per year 1 - 30 8 hrs $60.00 $9,764
Parts Allowance 1 - 30 1 LS $150.00 $3,051
AHU maintenance, 4 hours, ea 1 - 30 8 hrs 60.00 $10,011
Filters 1 - 30 2 ea 150.00 $6,257
Pump maintenance 1 - 30 3 ea 200.00 $12,514
Replacement
Heat pump replacement 18 - 18 1 ea 24,000.00 $15,316
Salvage Value
Loopfield (assume 75-year life) 30 - 30 -1 ea 63,450.00 ($30,014)
Total Annual Costs $107,000
Energy Costs Years Qty Unit Base Cost Present Value
Fuel Oil 1 - 30 800 gals $4.01 $113,430
Electricity, Years 1-2 1 - 2 41,542 kWh $0.109 $9,512
Electricity, Years 3-30 3 - 30 41,542 kWh $0.13 $94,511
Total Energy Costs $217,000
$812,000Present Worth
Page 4
Alaska Energy Engineering LLC Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 alaskaenergy@earthlink.net
Kettleson Memorial Library Renewable Energy Feasibility Study
Seawater Heat Pump System -Existing Building
Basis
Economic Factors Energy Inflation
Study Period (years) 30 Fuel Oil 6.6%
Nominal Discount Rate 5.5% Electricity, Yrs 1-2 9.0%
General Inflation 2.90% Electricity, Yrs 3-30 2.5%
Real Discount Rate 2.5%
Construction Costs Qty Unit Base Cost Year 0 Cost
Building Costs
Additional mechanical space 125 sqft 450.00 $56,250
Seawater Well
Increase well depth, 30' deep 30 lnft $125 $3,750
Increase intake or well pump capacity by 50 gpm 1 ls 5,000.00 $5,000
Underground piping to building 350 lnft 125.00 $43,750
Seawater piping in building 1 ls 8,000.00 $8,000
Seawater heat exchanger and appurtenances, titanium 1 ls 40,000.00 $40,000
Storm drain discharge to 60" culvert 150 lnft 40.00 $6,000
Heating System
200 MBH water-to-water heat pump 1 ls $35,000.00 $35,000
Evaporator pump, 0.5 HP 1 ea 1,500.00 $1,500
Condenser pump, 0.5 HP 1 ea 1,500.00 $1,500
Heating tank, 200 gallons 1 ls $6,000.00 $6,000
Connect fuel oil boilers to tank 1 ls $2,500.00 $2,500
Connect building hydronic loop to tank 1 ls $2,500.00 $2,500
Distribution
Replace AHU heating coils 2 ea $3,000.00 $6,000
Replace reheat coils 4 ea $750.00 $3,000
DDC Controls
Heating 12 pts $2,000.00 $24,000
Electrical
Electrical, 3-phase power 1 ls 3,500 $3,500
Electrical, 1-phase power 2 ls 1,500 $3,000
Contingencies
Design contingency 20% $50,250.00
General Overhead & Profit 30% $90,450.00
Design fees 10% $39,195.00
Owner's project costs 8% $34,491.60
Total Construction Costs $466,000
0
June 27, 2012
Year
0
0
0
0
0
0
0
0
0
0
0
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0
0
0
0
0
0
0
0
Page 5
Alaska Energy Engineering LLC Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 alaskaenergy@earthlink.net
Kettleson Memorial Library Renewable Energy Feasibility Study
Seawater Heat Pump System -Existing Building
June 27, 2012
Maintenance Costs Years Qty Unit Base Cost Present Value
Maintenance and Repair
Heat Pump
Daily: 5 minutes per day 1 - 30 30 hrs $60.00 $37,124
Monthly: 30 minutes per month 1 - 30 6 hrs $60.00 $7,323
Every Three Months: 30 minutes each 1 - 30 2 hrs $110.00 $4,475
Annual: 8 hours per year 1 - 30 8 hrs $110.00 $17,901
Contracted Tune-up: Every Five Years 5 - 5 1 ls $1,500.00 $1,291
Contracted Tune-up: Every Five Years 10 - 10 1 ls $1,500.00 $1,140
Contracted Tune-up: Every Five Years 15 - 15 1 ls $1,500.00 $1,006
Contracted Tune-up: Every Five Years 20 20 1 ls $1,500.00 $888
Contracted Tune-up: Every Five Years 25 25 1 ls $1,500.00 $784
Parts Allowance 1 - 30 1 LS $200.00 $4,068
Heat exchanger cleaning 1 - 30 8 hrs $60.00 $9,764
Boiler Maintenance
Monthly: 1 hours per month 1 - 30 12 hrs $60.00 $14,646
Annual: 8 hours, 1x per year 1 - 30 8 hrs $60.00 $9,764
Parts Allowance 1 - 30 1 LS $150.00 $3,051
AHU maintenance, 4 hours, ea 1 - 30 8 hrs 60.00 $10,011
Filters 1 - 30 2 ea 150.00 $6,257
Pump maintenance 1 - 30 3 ea 200.00 $12,514
Replacement
Heat pump replacement 18 - 18 1 ea 28,000.00 $17,869
Total Annual Costs $160,000
Energy Costs Years Qty Unit Base Cost Present Value
Fuel Oil 1 - 30 200 gals $4.01 $28,358
Electricity, Years 1-2 1 - 2 43,062 kWh $0.109 $9,860
Electricity, Years 3-30 3 - 30 43,062 kWh $0.13 $97,968
Total Energy Costs $136,000
$762,000Present Worth
Page 6
Alaska Energy Engineering LLC Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 alaskaenergy@earthlink.net
Kettleson Memorial Library Renewable Energy Feasibility Study
Air Source Heat Pump System -Existing Building
Basis
Economic Factors Energy Inflation
Study Period (years) 30 Fuel Oil 6.6%
Nominal Discount Rate 5.5% Electricity, Yrs 1-2 9.0%
General Inflation 2.90% Electricity, Yrs 3-30 2.5%
Real Discount Rate 2.5%
Construction Costs Qty Unit Base Cost Year 0 Cost
Architectural
Mechanical Space 200 ea $500.00 $100,000
Outdoor Units
Outdoor heat pump unit
Material 3 ea $10,000 $30,000
Installation 3 ea $2,500 $7,500
Discharge ductwork 3 ea $2,500 $7,500
Electrical service 3 ea $2,500 $7,500
Heating System
Indoor hydronic heat exchanger 3 ea $6,000 $18,000
Installation 3 ea $1,500 $4,500
Heating tank, 150 gallons 1 ls $6,000.00 $6,000
Connect fuel oil boilers to tank 1 ls $2,500.00 $2,500
Connect building hydronic loop to tank 1 ls $2,500.00 $2,500
Distribution
Replace AHU heating coils 2 ea $3,000.00 $6,000
Replace reheat coils 4 ea $600.00 $2,400
DDC Controls
Heating 8 pts $2,000.00 $16,000
Contingencies
Design contingency 20% $42,080.00
General Overhead & Profit 30% $75,744.00
Design fees 10% $32,822.40
Owner's project costs 8% $28,883.71
Total Construction Costs $390,000
0
0
0
0
June 27, 2012
Year
0
0
0
0
0
0
0
0
0
0
0
0
0
Page 7
Alaska Energy Engineering LLC Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 alaskaenergy@earthlink.net
Kettleson Memorial Library Renewable Energy Feasibility Study
Air Source Heat Pump System -Existing Building
June 27, 2012
Maintenance Costs Years Qty Unit Base Cost Present Value
Heat Pump Maintenance
Daily: 10 minutes per day 1 - 30 61 hrs $60.00 $74,248
Monthly: 1/2 hour per month ea 1 - 30 18 hrs $60.00 $21,969
Every Three Months: 40 minutes ea 1 - 30 8 hrs $110.00 $17,901
Annual: 8 hours per year each 1 - 30 24 hrs $110.00 $53,703
Parts Allowance 1 - 30 3 ea $250.00 $15,256
Replacement
Outdoor units 12 - 12 3 ea $12,500.00 $27,796
Outdoor units 24 - 24 3 ea $12,500.00 $20,604
Total Annual Costs $231,000
Energy Costs Years Qty Unit Base Cost Present Value
Fuel Oil 1 - 30 200 gals $4.01 $28,358
Electricity, Years 1-2 1 - 2 52,189 kWh $0.109 $11,950
Electricity, Years 3-30 3 - 30 52,189 kWh $0.13 $118,731
Total Energy Costs $159,000
$780,000Present Worth
Page 8
Alaska Energy Engineering LLC Conceptual Sizing
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Renovated Library
BASELINE
Sizing Existing Boilers Boiler Net MBH Area Btu/sqft
B-1 448 7,500 60 High
Renovated Building Area Btu/sqft MBH
12,000 30 360
Energy Consumption
Comparison to Existing Building Efficiency gains -20%
Area increase 60%
40%
Exist, gal Increase Fuel Oil, gal Efficiency kBTU/gal Heat, kBtu
Heat 4,000 40% 5,600 68% 138.5 527,408
Pumps Unit kW Hours kWh
Boiler Pump 0.2 2,500 600
GROUND SOURCE HEAT PUMP SYSTEM
Sizing Heating Plant Load, MBH Factor Size, MBH kWh Tons COP kW
Heat pump 360 50% 180 - 15 3.0 18
B-1 360 125%448
175% 628
Loopfield ft/ton Bore, lnft lnft/bore Bores Loops Bores/loop Spacing, ft Acres
250 3,750 313 12 2 6 30 0.2
Pumps Pump GPM/ea Head whp hp bhp
HP Evap 45 120 1.4 65% 2.1
HP Cond 45 25 0.3 65% 0.4
Electric Loads Load Qty BHP hm kW
Heat Pump 1 - - 17.6
Evap Pump 1 3 89% 2.5
Cond Pump 1 0.75 75% 0.7
Total 21
Electric Service Capacity Volts Amps KVA PF kW
208 200 72 84% 61
Calculated Peak Load 24
Additional peak 20%
Current peak demand 29
Available capacity 32
Heat Pump System 21
Spare Capacity 11
June 27, 2012
Page 9
Alaska Energy Engineering LLC Conceptual Sizing
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Renovated Library
June 27, 2012
Energy Analysis
Ground Source Heat Pump Heat kBTU % Load HP kBTU
527,408 95% 501,038
Month % Load kBtu Source Temp COP kBtu kWh
Jan 14% 70,145 32 2.6 26,979 7,907
Feb 11% 55,114 32 2.6 21,198 6,213
Mar 9% 45,093 32 2.6 17,344 5,083
Apr 8% 40,083 34 2.8 14,315 4,196
May 5% 25,052 36 3.0 8,351 2,447
Jun 3% 15,031 38 3.2 4,697 1,377
Jul 3% 15,031 40 3.4 4,421 1,296
Aug 5% 25,052 42 3.5 7,158 2,098
Sep 8% 40,083 40 3.4 11,789 3,455
Oct 9% 45,093 38 3.2 14,092 4,130
Nov 11% 55,114 36 3.0 18,371 5,384
Dec 14%70,145 34 2.8 25,052 7,342
100% 501,038 173,766 50,928
288%
Fuel Oil Boiler Heat kBtu % Load Boiler kBTU Efficiency kBTU/gal Fuel, gals
527,408 5% 26,370 68% 138.5 280
Pumps Unit kW Hours kWh
Boiler Pump 0.2 59 14
Evaporator 2.5 2,784 7,000
Condenser 0.7 2,784 2,077
9,090
SEAWATER HEAT PUMP SYSTEM
Sizing Heating Plant Unit Load, MBH Factor Size, MBH kWh Tons COP kW
Heat pump 360 70% 252 - 21 3.0 25
B-1 360 125%448
195% 700
Seawater Heat Exchanger Flow Inlet Outlet Spec Heat
Side gpm °F °F Btu/lb°F MBH Tons
Seawater 63 40.0 34.0 0.90 170 14
Evap 63 32.3 38.0 0.94 -170 -14
Pumps GPM Head whp hp bhp
Boiler 41 4 0.0 45% 0.1
Well 63 75 1.2 55% 2.2
Evaporator 63 20 0.3 50% 0.6
Condenser 63 20 0.3 60% 0.5
Page 10
Alaska Energy Engineering LLC Conceptual Sizing
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Renovated Library
June 27, 2012
Additional Electric Load
Load Qty BHP hm kW
Heat Pump 1 - - 24.6
Well pump 1 3.0 89% 2.5
Evaporator 1 0.75 85% 0.7
Condenser 1 0.50 75% 0.5
Total 28.3
Electric Service Capacity Volts Amps KVA PF kW
MDP Capacity 208 200 72 84% 61
Calculated Peak Load 24
Additional peak 20%
Current peak demand 29
Available capacity 32
Heat Pump System 28
Spare Capacity 3
Energy Analysis
Consumption
Seawater Well Heat Pump Heat kBTU % Load HP kBTU
527,408 95% 501,038
Month % Load kBtu Source Temp COP kBtu kWh
Jan 14% 70,145 40 3.4 20,631 6,047
Feb 11% 55,114 40 3.4 16,210 4,751
Mar 9% 45,093 40 3.4 13,263 3,887
Apr 8% 40,083 44 3.5 11,452 3,356
May 5% 25,052 47 3.6 6,959 2,040
Jun 3% 15,031 50 3.7 4,062 1,191
Jul 3% 15,031 52 3.8 3,956 1,159
Aug 5% 25,052 54 3.9 6,473 1,897
Sep 8% 40,083 52 3.8 10,548 3,091
Oct 9% 45,093 50 3.7 12,187 3,572
Nov 11% 55,114 47 3.6 15,309 4,487
Dec 14%70,145 44 3.5 20,042 5,874
100% 501,038 141,093 41,352
355%
Fuel Oil Boiler Load, kBTU % Load Net, kBTU Efficiency kBTU/gal Fuel, gals
527,408 5% 26,370 68% 138.5 280
Pumps kW Hours kWh
Boiler Pump 0.3 100 25
Well Pump 1.5 5,000 7,500
Evaporator 0.6 5,000 3,000
Condenser 0.6 5,000 3,000
13,525
Page 11
Alaska Energy Engineering LLC Conceptual Sizing
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Renovated Library
June 27, 2012
AIR SOURCE HEAT PUMP
Renovated Building
Equipment HP ERV Fan Coils
Auditorium 2 1 10
Additional Electric Load MBH kW
360 106 Backup electric resistance heat
Energy Analysis
Consumption kBtu
Baseline Heating Load 527,408
System Efficiency Gain 10%
Net Load 474,667
Month % Load kBtu Backup %Backup, kBtu Ave Temp COP kBtu kWh
Jan 14% 66,453 5% 3,323 33 1.9 33,863 10,898
Feb 11% 52,213 5% 2,611 35 2.0 25,404 8,211
Mar 9% 42,720 5% 2,136 37 2.1 19,738 6,411
Apr 8% 37,973 5% 1,899 40 2.2 16,121 5,281
May 5% 23,733 5% 1,187 46 2.7 8,443 2,822
Jun 3% 14,240 5% 712 49 2.9 4,663 1,575
Jul 3% 14,240 5% 712 54 3.3 4,150 1,425
Aug 5% 23,733 5% 1,187 55 3.3 6,787 2,337
Sep 8% 37,973 5% 1,899 52 3.1 11,547 3,941
Oct 9% 42,720 5% 2,136 44 2.5 16,111 5,348
Nov 11% 52,213 5% 2,611 39 2.2 22,816 7,452
Dec 14%66,453 5%3,323 32 1.8 36,390 11,639
100% 474,667 23,733 206,033 67,341
219%
kBtu
Cooling Load 71,200
Month % Load kBtu Ave Temp COP kBtu kWh
Jun 20% 14,240 49 4.0 3,580 1,049
Jul 40% 28,480 54 3.9 7,244 2,123
Aug 40%28,480 55 3.9 7,261 2,128
100% 71,200 18,084 5,300
394%
Page 12
Alaska Energy Engineering LLC Summary
25200 Amalga Harbor Road Tel/Fax: 907-789-1226
Juneau, Alaska 99801 alaskaenergy@earthlink.net
Kettleson Memorial Library Renewable Energy Feasibility Study
Renovated Library Heating System Optimization Analysis
Baseline Economic Factors
Economic Factors Energy Inflation
Study Period (years) 30 Fuel Oil 6.6%
Nominal Discount Rate 5.5% Electricity, Yrs 1-2 9.0%
General Inflation 2.90% Electricity, Yrs 3-30 2.5%
Base Case: 6.6% Fuel Oil, 2.5% Electricity Construction Maintenance Energy Total
Baseline Fuel Oil Boilers - Renovation and Expansion $392,000 $138,000 $796,000 $1,326,000
Ground Source Heat Pump System - Renovation and Expansion $623,000 $151,000 $190,000 $964,000
Seawater Heat Pump System - Renovation and Expansion $491,000 $194,000 $177,000 $862,000
Air Source Heat Pump System - Renovation and Expansion $560,000 $302,000 $180,000 $1,042,000
High Fuel Oil Case: 8% Fuel Oil, 2.5% Electricity Construction Maintenance Energy Total
Baseline Fuel Oil Boilers - Renovation and Expansion $392,000 $138,000 $990,000 $1,520,000
Ground Source Heat Pump System - Renovation and Expansion $623,000 $151,000 $200,000 $974,000
Seawater Heat Pump System - Renovation and Expansion $491,000 $194,000 $187,000 $872,000
Air Source Heat Pump System - Renovation and Expansion $560,000 $302,000 $180,000 $1,042,000
Low Fuel Oil Case: 4.8% Fuel Oil, 2.5% Electricity Construction Maintenance Energy Total
Baseline Fuel Oil Boilers - Renovation and Expansion $392,000 $138,000 $610,000 $1,140,000
Ground Source Heat Pump System - Renovation and Expansion $623,000 $151,000 $181,000 $955,000
Seawater Heat Pump System - Renovation and Expansion $491,000 $194,000 $168,000 $853,000
Air Source Heat Pump System - Renovation and Expansion $560,000 $302,000 $180,000 $1,042,000
High Electricity Case: 6.6% Fuel Oil, 4% Electricity Construction Maintenance Energy Total
Baseline Fuel Oil Boilers - Renovation and Expansion $392,000 $138,000 $796,000 $1,326,000
Ground Source Heat Pump System - Renovation and Expansion $623,000 $151,000 $219,000 $993,000
Seawater Heat Pump System - Renovation and Expansion $491,000 $194,000 $203,000 $888,000
Air Source Heat Pump System - Renovation and Expansion $560,000 $302,000 $220,000 $1,082,000
Low Electricity Case: 6.6% Fuel Oil, 1% Electricity Construction Maintenance Energy Total
Baseline Fuel Oil Boilers - Renovation and Expansion $392,000 $138,000 $795,000 $1,325,000
Ground Source Heat Pump System - Renovation and Expansion $623,000 $151,000 $168,000 $942,000
Seawater Heat Pump System - Renovation and Expansion $491,000 $194,000 $157,000 $842,000
Air Source Heat Pump System - Renovation and Expansion $560,000 $302,000 $150,000 $1,012,000
June 27, 2012
Present Worth
Page 13
Alaska Energy Engineering LLC Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 alaskaenergy@earthlink.net
Kettleson Memorial Library Renewable Energy Feasibility Study
Baseline Fuel Oil Boilers -Renovation and Expansion
Basis
Economic Factors Energy Inflation
Study Period (years) 30 Fuel Oil 6.6%
Nominal Discount Rate 5.5% Electricity, Yrs 1-2 9.0%
General Inflation 2.90% Electricity, Yrs 3-30 2.5%
Real Discount Rate 2.5%
Construction Costs Qty Unit Base Cost Year 0 Cost
Heating Plant
Refurbish existing boiler 1 ea $1,500.00 $1,500
Secondary pumps with VFDs 2 ea $7,500.00 $15,000
Hydronic Heating System
Insulated hydronic piping (3/4" to 3"), supports, seismic 420 lnft 42.00 17,640
AHU heating coils 1 ea 4,000.00 4,000
Unit heaters 1 ea 1,250.00 1,250
Cabinet unit heaters 2 ea 1,500.00 3,000
Terminal box reheat coil and valves 10 ea 750.00 7,500
Ventilation Systems
AHU-1: Library 14,000 cfm 5.00 70,000
Ductwork 3,500 lbs 9.00 31,500
VAV boxes 10 ea 675.00 6,750
Grilles and diffusers 40 ea 137.00 5,480
Sound attenuators 1 lot 8,000.00 8,000
Outside air louver and damper 28 sqft 57.00 1,596
Miscellaneous dampers, etc. 1 lot 4,000.00 4,000
DDC Controls
Heating and cooling 15 pts $1,600.00 $24,000
Electrical
Electrical, 3-phase power 1 ls 7,500 $7,500
Electrical, 1-phase power 2 ls 1,500 $3,000
Contingencies
Design contingency 20% $42,343.20
General Overhead & Profit 30% $76,217.76
Design fees 10% $33,027.70
Owner's project costs 8% $29,064.37
Total Construction Costs $392,000
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Page 14
Alaska Energy Engineering LLC Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 alaskaenergy@earthlink.net
Kettleson Memorial Library Renewable Energy Feasibility Study
Baseline Fuel Oil Boilers -Renovation and Expansion
June 27, 2012
Maintenance Costs Years Qty Unit Base Cost Present Value
Maintenance and Repair
Boiler Maintenance
Daily: 5 minutes per day 1 - 30 30 hrs $60.00 $37,124
Monthly: 2 hours per month 1 - 30 24 hrs $60.00 $29,292
Annual: 8 hours, 2x per year 1 - 30 16 hrs $60.00 $19,528
Parts Allowance 1 - 30 1 LS $150.00 $3,051
Boiler Maintenance
Monthly: 1 hours per month 1 - 30 12 hrs $60.00 $14,646
Annual: 8 hours, 1x per year 1 - 30 8 hrs $60.00 $9,764
Parts Allowance 1 - 30 1 LS $150.00 $3,051
AHU maintenance, 4 hours, ea 1 - 30 4 hrs 60.00 $5,005
Filters 1 - 30 1 ea 200.00 $4,171
Pump maintenance 1 - 30 3 ea 200.00 $12,514
Total Annual Costs $138,000
Energy Costs Years Qty Unit Base Cost Present Value
Fuel Oil 1 - 30 5,600 gals $4.01 $794,011
Electricity, Years 1-2 1 - 2 600 kWh $0.109 $137
Electricity, Years 3-30 3 - 30 600 kWh $0.13 $1,365
Total Energy Costs $796,000
$1,326,000Present Worth
Page 15
Alaska Energy Engineering LLC Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 alaskaenergy@earthlink.net
Kettleson Memorial Library Renewable Energy Feasibility Study
Ground Source Heat Pump System -Re novation and Expansion
Basis
Economic Factors Energy Inflation
Study Period (years) 30 Fuel Oil 6.6%
Nominal Discount Rate 5.5% Electricity, Yrs 1-2 9.0%
General Inflation 2.90% Electricity, Yrs 3-30 2.5%
Real Discount Rate 2.53%
Construction Costs Qty Unit Base Cost Year 0 Cost
Building Costs
Additional mechanical space 125 sqft 450.00 $56,250
Loopfield
Loopfield: Boreholes, pipe loop, backfill, horizontal piping 3,750 lnft 36.00 $135,000
Loopfield header and piping in building 1 ls 15,000.00 $15,000
Heating System
220 MBH water-to-water heat pump 1 ls $36,000 $36,000
Source pump, 3 HP with VFD 1 ea 6,500.00 $6,500
Load pump, 0.75 HP 1 ea 1,700.00 $1,700
Heating tank, 150 gallons 1 ls $6,000.00 $6,000
Secondary pumps with VFDs 2 ea $7,500.00 $15,000
Distribution
Replace AHU heating coils 2 ea $3,000.00 $6,000
Replace reheat coils 4 ea $500.00 $2,000
DDC Controls
Heating 12 pts $1,600.00 $19,200
Electrical
Electrical, 3-phase power 5 ls 7,500 $37,500
Contingencies
Design contingency 20% $67,230.00
General Overhead & Profit 30% $121,014.00
Design fees 10% $52,439.40
Owner's project costs 8% $46,146.67
Total Construction Costs $623,000
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Page 16
Alaska Energy Engineering LLC Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 alaskaenergy@earthlink.net
Kettleson Memorial Library Renewable Energy Feasibility Study
Ground Source Heat Pump System -Re novation and Expansion
June 27, 2012
Maintenance Costs Years Qty Unit Base Cost Present Value
Maintenance and Repair
Heat Pump
Daily: 10 minutes per day 1 - 30 61 hrs $60.00 $74,248
Monthly: 30 minutes per month 1 - 30 6 hrs $60.00 $7,323
Every Three Months: 30 minutes each 1 - 30 2 hrs $110.00 $4,475
Annual: 8 hours per year 1 - 30 8 hrs $110.00 $17,901
Contracted Tune-up: Every Five Years 5 - 5 1 ls $1,500.00 $1,291
Contracted Tune-up: Every Five Years 10 - 10 1 ls $1,500.00 $1,140
Contracted Tune-up: Every Five Years 15 - 15 1 ls $1,500.00 $1,006
Contracted Tune-up: Every Five Years 20 20 1 ls $1,500.00 $888
Contracted Tune-up: Every Five Years 25 25 1 ls $1,500.00 $784
Parts Allowance 1 - 30 1 LS $200.00 $4,068
Boiler Maintenance
Monthly: 1 hours per month 1 - 30 12 hrs $60.00 $14,646
Annual: 8 hours, 1x per year 1 - 30 8 hrs $60.00 $9,764
Parts Allowance 1 - 30 1 LS $150.00 $3,051
AHU maintenance, 4 hours, ea 1 - 30 4 hrs 60.00 $5,005
Filters 1 - 30 1 ea 200.00 $4,171
Pump maintenance 1 - 30 5 ea 200.00 $20,856
Replacement
Heat pump replacement 18 - 18 1 ea 28,800.00 $18,379
Salvage Value
Loopfield (assume 75-year life) 30 - 30 -1 ea 81,000.00 ($38,315)
Total Annual Costs $151,000
Energy Costs Years Qty Unit Base Cost Present Value
Fuel Oil 1 - 30 280 gals $4.01 $39,701
Electricity, Years 1-2 1 - 2 60,018 kWh $0.109 $13,742
Electricity, Years 3-30 3 - 30 60,018 kWh $0.13 $136,544
Total Energy Costs $190,000
$964,000Present Worth
Page 17
Alaska Energy Engineering LLC Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 alaskaenergy@earthlink.net
Kettleson Memorial Library Renewable Energy Feasibility Study
Seawater Heat Pump System -Renovation an d Expansion
Basis
Economic Factors Energy Inflation
Study Period (years) 30 Fuel Oil 6.6%
Nominal Discount Rate 5.5% Electricity, Yrs 1-2 9.0%
General Inflation 2.90% Electricity, Yrs 3-30 2.5%
Real Discount Rate 2.5%
Construction Costs Qty Unit Base Cost Year 0 Cost
Building Costs
Additional mechanical space 150 sqft 450.00 $67,500
Seawater Well
Increase well depth, 50' deep 50 lnft $125 $6,250
Increase intake or well pump capacity by 65 gpm 1 ls 7,500.00 $7,500
Underground piping to building 350 lnft 160.00 $56,000
Seawater piping in building 1 ls 8,000.00 $8,000
Seawater heat exchanger and appurtenances, titanium 1 ls 30,000.00 $30,000
Storm drain discharge to 60" culvert 1 ls 8,000.00 $8,000
Heating System
200 MBH water-to-water heat pump 1 ls $35,000.00 $35,000
Evaporator pump, 0.5 HP 1 ea 1,500.00 $1,500
Condenser pump, 0.5 HP 1 ea 1,500.00 $1,500
Heating tank, 200 gallons 1 ls $6,000.00 $6,000
Distribution
Replace AHU heating coils 2 ea $3,000.00 $6,000
Replace reheat coils 4 ea $500.00 $2,000
DDC Controls
Heating 12 pts $1,600.00 $19,200
Electrical
Electrical, 3-phase power 1 ls 7,500 $7,500
Electrical, 1-phase power 2 ls 1,500 $3,000
Contingencies
Design contingency 20% $52,990.00
General Overhead & Profit 30% $95,382.00
Design fees 10% $41,332.20
Owner's project costs 8% $36,372.34
Total Construction Costs $491,000
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Page 18
Alaska Energy Engineering LLC Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 alaskaenergy@earthlink.net
Kettleson Memorial Library Renewable Energy Feasibility Study
Seawater Heat Pump System -Renovation an d Expansion
June 27, 2012
Maintenance Costs Years Qty Unit Base Cost Present Value
Maintenance and Repair
Heat Pump
Daily: 10 minutes per day 1 - 30 61 hrs $60.00 $74,248
Monthly: 30 minutes per month 1 - 30 6 hrs $60.00 $7,323
Every Three Months: 30 minutes each 1 - 30 2 hrs $110.00 $4,475
Annual: 8 hours per year 1 - 30 8 hrs $110.00 $17,901
Contracted Tune-up: Every Five Years 5 - 5 1 ls $1,500.00 $1,291
Contracted Tune-up: Every Five Years 10 - 10 1 ls $1,500.00 $1,140
Contracted Tune-up: Every Five Years 15 - 15 1 ls $1,500.00 $1,006
Contracted Tune-up: Every Five Years 20 20 1 ls $1,500.00 $888
Contracted Tune-up: Every Five Years 25 25 1 ls $1,500.00 $784
Parts Allowance 1 - 30 1 LS $200.00 $4,068
Heat exchanger cleaning 1 - 30 8 hrs $60.00 $9,764
Boiler Maintenance
Monthly: 1 hours per month 1 - 30 12 hrs $60.00 $14,646
Annual: 8 hours, 1x per year 1 - 30 8 hrs $60.00 $9,764
Parts Allowance 1 - 30 1 LS $150.00 $3,051
AHU maintenance, 4 hours, ea 1 - 30 4 hrs 60.00 $5,005
Filters 1 - 30 1 ea 200.00 $4,171
Pump maintenance 1 - 30 4 ea 200.00 $16,685
Replacement
Heat pump replacement 18 - 18 1 ea 28,000.00 $17,869
Total Annual Costs $194,000
Energy Costs Years Qty Unit Base Cost Present Value
Fuel Oil 1 - 30 280 gals $4.01 $39,701
Electricity, Years 1-2 1 - 2 54,877 kWh $0.109 $12,565
Electricity, Years 3-30 3 - 30 54,877 kWh $0.13 $124,847
Total Energy Costs $177,000
$862,000Present Worth
Page 19
Alaska Energy Engineering LLC Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 alaskaenergy@earthlink.net
Kettleson Memorial Library Renewable Energy Feasibility Study
Air Source Heat Pump System -Renovation and Expansion
Basis
Economic Factors Energy Inflation
Study Period (years) 30 Fuel Oil 6.6%
Nominal Discount Rate 5.5% Electricity, Yrs 1-2 9.0%
General Inflation 2.90% Electricity, Yrs 3-30 2.5%
Real Discount Rate 2.5%
Construction Costs Qty Unit Base Cost Year 0 Cost
Architectural
Louvered enclosure for outdoor units 64 sqft $400 $25,600
Heating Plant
Demolish fuel oil boilers and appurtenances 1 ea $5,000 $5,000
Demolish fuel oil system 1 ea $2,500 $2,500
Outdoor Units
Outdoor heat pump unit
Material 2 ea $8,000 $16,000
Installation 2 ea $2,000 $4,000
Discharge ductwork 2 ea $2,500 $5,000
Electrical service 2 ea $2,500 $5,000
Controlled mixing boxes
Material 2 ea $4,200 $8,400
Installation 2 ea $500 $1,000
Connections 10 ea $200 $2,000
Piping from outdoor units 2 ea $2,500 $5,000
Valves 24 ea $55 $1,320
Energy Recovery Ventilators
Intake louver and ductwork 1 ea $3,500 $3,500
Discharge louver and ductwork 1 ea $3,500 $3,500
Energy recovery ventilator
Material 1 ea $8,500 $8,500
Installation 1 ea $1,500 $1,500
Supply ductwork to terminal units 150 lnft $60 $9,000
Electrical service 1 ea $7,500 $7,500
Terminal Units
Duct mounted fan coil units
Material 10 ea $1,750 $17,500
Installation 10 ea $500 $5,000
Piping from controlled mixing box 10 ea $600 $6,000
Supply ductwork to diffusers 10 ea $1,200 $12,000
Electric service 10 ea $1,200 $12,000
Piping to ERV coils 75 lnft $30 $2,250
ERV heating coils 1 ea $1,000 $1,000
Sound traps 1 ea $4,000 $4,000
Thermostats 10 ea $170 $1,700
Electrical
Larger electric service and distribution, 100 kW 1 ls $25,000 $25,000
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Page 20
Alaska Energy Engineering LLC Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 alaskaenergy@earthlink.net
Kettleson Memorial Library Renewable Energy Feasibility Study
Air Source Heat Pump System -Renovation and Expansion
June 27, 2012
Construction Costs Qty Unit Base Cost Year 0 Cost
Controls
Material 1 LS $25,000 $25,000
Installation 1 LS $75,000 $75,000
Contingencies
Design contingency 20% $60,154.00
General Overhead & Profit 30% $108,277.20
Design fees 10% $46,920.12
Owner's project costs 8% $41,289.71
Total Construction Costs $560,000
Maintenance Costs Years Qty Unit Base Cost Present Value
Heat Pump Maintenance
Daily: 10 minutes per day 1 - 30 61 hrs $60.00 $74,248
Monthly: 4 hours per month 1 - 30 48 hrs $60.00 $58,585
Every Three Months: 4 hours 1 - 30 16 hrs $110.00 $35,802
Annual: 8 hours per year 1 - 30 8 hrs $110.00 $17,901
Parts Allowance 1 - 30 1 LS $250.00 $5,085
Fan coils
Filter replacement 1 - 30 10 ea $100.00 $20,856
Maintenance 1 - 30 10 ea $60.00 $12,514
Energy Recovery Ventilators
Filter replacement 1 - 30 1 ea $200.00 $4,171
Maintenance
Daily, 5 minutes per day 1 - 30 22 hrs 60.00 $27,113
Annual: 1 day 1 - 30 4 hrs 60.00 $5,005
Replacement
Outdoor units 12 - 12 2 ea $9,000.00 $13,342
Outdoor units 24 - 24 2 ea $9,000.00 $9,890
Energy recovery ventilators 20 - 20 1 ea $9,250.00 $5,616
Fan coil units 20 - 20 10 ea $2,000.00 $12,142
Total Annual Costs $302,000
Energy Costs Years Qty Unit Base Cost Present Value
Fuel Oil 1 - 30 0 gals $4.01 $0
Electricity, Years 1-2 1 - 2 72,641 kWh $0.109 $16,632
Electricity, Years 3-30 3 - 30 72,641 kWh $0.13 $165,261
Total Energy Costs $180,000
$1,042,000Present Worth
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Page 21