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HomeMy WebLinkAboutSitka Centennial Hall Air Source Heat Pump Project Feasibility Analysis - Jul 2012 - REF Grant 7071011Renewable Energy Feasibility Analysis Harrigan Centennial Hall Kettleson Memorial Library City and Borough of Sitka Prepared by: Final Report July, 2012 Alaska Energy Engineering LLC Blank Page Alaska Energy Engineering LLC 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 Alaska Energy Engineering LLC Centennial Hall and Library 2 Renewable Energy Feasibility Analysis Blank page Alaska Energy Engineering LLC Centennial Hall and Library 3 Renewable Energy Feasibility Analysis 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. Alaska Energy Engineering LLC Centennial Hall and Library 4 Renewable Energy Feasibility Analysis 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. Alaska Energy Engineering LLC Centennial Hall and Library 5 Renewable Energy Feasibility Analysis 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. Alaska Energy Engineering LLC Centennial Hall and Library 6 Renewable Energy Feasibility Analysis Blank page Alaska Energy Engineering LLC Centennial Hall and Library 7 Renewable Energy Feasibility Analysis 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. Alaska Energy Engineering LLC Centennial Hall and Library 8 Renewable Energy Feasibility Analysis 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. Alaska Energy Engineering LLC Centennial Hall and Library 9 Renewable Energy Feasibility Analysis 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) Alaska Energy Engineering LLC Centennial Hall and Library 10 Renewable Energy Feasibility Analysis 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. Alaska Energy Engineering LLC Centennial Hall and Library 11 Renewable Energy Feasibility Analysis 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. Alaska Energy Engineering LLC Centennial Hall and Library 12 Renewable Energy Feasibility Analysis 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: Alaska Energy Engineering LLC Centennial Hall and Library 13 Renewable Energy Feasibility Analysis 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. Alaska Energy Engineering LLC Centennial Hall and Library 14 Renewable Energy Feasibility Analysis Blank page Alaska Energy Engineering LLC Centennial Hall and Library 15 Renewable Energy Feasibility Analysis 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. Alaska Energy Engineering LLC Centennial Hall and Library 16 Renewable Energy Feasibility Analysis 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. Alaska Energy Engineering LLC Centennial Hall and Library 17 Renewable Energy Feasibility Analysis 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. Alaska Energy Engineering LLC Centennial Hall and Library 18 Renewable Energy Feasibility Analysis 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. Alaska Energy Engineering LLC Centennial Hall and Library 19 Renewable Energy Feasibility Analysis 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. Alaska Energy Engineering LLC Centennial Hall and Library 20 Renewable Energy Feasibility Analysis 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. Alaska Energy Engineering LLC Centennial Hall and Library 21 Renewable Energy Feasibility Analysis 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. Alaska Energy Engineering LLC Centennial Hall and Library 22 Renewable Energy Feasibility Analysis 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. Alaska Energy Engineering LLC Centennial Hall and Library 23 Renewable Energy Feasibility Analysis 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. Alaska Energy Engineering LLC Centennial Hall and Library 24 Renewable Energy Feasibility Analysis 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. Alaska Energy Engineering LLC Centennial Hall and Library 25 Renewable Energy Feasibility Analysis 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. Alaska Energy Engineering LLC Centennial Hall and Library 26 Renewable Energy Feasibility Analysis Blank page Alaska Energy Engineering LLC Centennial Hall and Library 27 Renewable Energy Feasibility Analysis 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. Alaska Energy Engineering LLC Centennial Hall and Library 28 Renewable Energy Feasibility Analysis 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. Alaska Energy Engineering LLC Centennial Hall and Library 29 Renewable Energy Feasibility Analysis 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. Alaska Energy Engineering LLC Centennial Hall and Library 30 Renewable Energy Feasibility Analysis 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%. Alaska Energy Engineering LLC Centennial Hall and Library 31 Renewable Energy Feasibility Analysis 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. Alaska Energy Engineering LLC Centennial Hall and Library 32 Renewable Energy Feasibility Analysis 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. Alaska Energy Engineering LLC Centennial Hall and Library 34 Renewable Energy Feasibility Analysis Blank page Alaska Energy Engineering LLC 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 Blank page Alaska Energy Engineering LLC Appendix A Centennial Hall Schematic 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 LLC Appendix B Centennial Hall 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 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 Page 1 Alaska Energy Engineering LLC Conceptual Sizing 25200 Amalga Harbor Road Tel/Fax: 907.789.1226 Juneau, Alaska 99801 jim@alaskaenergy.us 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 Page 2 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 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 Page 3 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 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 Page 4 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 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 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 July 7, 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 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 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 July 7, 2012 Year 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 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 0 0 Year 0 0 Present Worth 0 0 0 0 0 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 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 July 7, 2012 Year 0 0 0 0 0 0 0 0 0 0 0 0 0 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 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Year 0 0 0 0 0 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 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 July 7, 2012 Year 0 0 0 0 0 0 0 0 0 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 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Year 0 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 0 0 0 0 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 0 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 0 0 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 0 0 0 0 0 0 0 0 0 June 27, 2012 Year 0 0 0 0 0 0 0 0 0 0 0 0 0 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 0 June 27, 2012 Year 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 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 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 June 27, 2012 Year 0 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 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 June 27, 2012 Year 0 0 0 0 0 0 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 0 0 0 0 0 0 Year Page 21