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HomeMy WebLinkAboutEvaluation of Water Source Heat Pumps for the Juneau, AK Area 19805.346 RECEIVED AUG 1 4 1980 ‘ALASKA POWER AUTHORITY a A RRA BESTE POT TRY SET EE ea aR Evaluation of Water Source Heat Pumps for the Juneau, Alaska Area SS Rr ae a EI ESS TS a July 1980 Prepared for the Alaska Power Administration under a Related Services Agreement with the U.S. Department of Energy under Contract DE-AC06-76RLO 1830 Pacific Northwest Laboratory Operated for the U.S. Department of Energy by Battelle Memorial Institute Liz ARY COP PROPERTY OF: Alaska Power Authority 334 W. 5th Ave. _ Anchorage, Alaska 99501 WOETTCE r This report was prepared as an account of work sponsored by the United States Government. Neither the United States nor the Department of Energy, nor any of their employees, nor any of their contractors, subcontractors, or their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness or usefulness of any information, apparatus, product or process disclosed, or represents that its use would not infringe privately owned rights. The views, opinions and conclusions contained in this report are those of the contractor and do not necessarily represent those of the United States Government or the United States Department of Energy. a | CONTENTS FIGURES TABLES PREFACE AND ACKNOWLEDGMENTS 1.0 2.0 3.0 4.0 5.0 INTRODUCTION SUMMARY OF RESULTS SURVEY OF WATER SOURCE HEAT PUMP MANUFACTURERS ASSESSMENT OF FOULING AND CORROSION PROBLEMS RELATED TO USE OF SEA WATER AS A HEAT SOURCE . . 4.1 ASSESSMENT OF FOULING PROBLEMS 4.2 ASSESSMENT OF CORROSION PROBLEMS CONCEPTUAL DESIGN OF WATER R SOURCE HEAT PUMP HEATING SYSTEMS : 5.1 INTRODUCTION 5.2 BUILDING DESIGNS AND HEAT PUMP SYSTEMS 5.2.1 New Residential Construction in the Mendenhall Valley . 5.2.2 Filter Building at the Auke Bay Laboratory . 5.2.3 Warehouse on Juneau Waterfront 5.2.4 Salmon Hatchery Near Snettisham Hydroelectric Project 5.3 HEAT LOAD METHODOLOGY AND ANALYSES . 5.4 HEAT PUMP SYSTEM DESIGNS . 5.4.1 Mendenhall Valley Residence . 5.4.2 Auke Bay Filter Building 5.4.3 Warehouse on the Juneau Waterfront 5.4.4 Snettisham Salmon Hatchery iii a a oOo mM uo vii ix -10 11 12 -14 17 6.0 EVALUATION OF ALTERNATIVE DESIGNS 6.1 INTRODUCTION 6.2 LIFE CYCLE COST COMPARISONS 6.2.1 6.2.2 6.2.3 6.2.4 New Residential Construction in the Mendenhall Valley . Filter Building at the Auke Bay Laboratory : : . Warehouse on the Juneau Waterfront Salmon Hatchery Near Snettisham Hydroelectric Project 6.3 TECHNICAL VIABILITY OF WSHPs IN THE JUNEAU AREA 6.3.1 6.3.2 6.3.3 6.3.4 6.3.5 General Considerations . New Residential Construction in the Mendenhall Valley . Filter Building at the Auke Bay Laboratory . Warehouse on the Juneau Waterfront Salmon Hatchery 6.4 EFFECTS ON ELECTRICAL AND FOSSIL FUEL USAGE 7.0 RECOMMENDATIONS FOR VERIFICATION PROGRAM AND ADDITIONAL RESEARCH . . . 7.1 RECOMMENDATIONS FOR VERIFICATION PROGRAM 7.2 RECOMMENDATIONS FOR ADDITIONAL RESEARCH . APPENDIX A - ADDITIONAL INFORMATION FROM WATER SOURCE HEAT PUMP MANUFACTURER SURVEY APPENDIX B - HEAT LOAD CALCULATIONS APPENDIX C - DETAILED HEATING SYSTEM DESIGN INFORMATION APPENDIX D - LIFE CYCLE COST CALCULATIONS iv a nn Dn Dn OD OQ ao . . ee o . FP RF 12 15 17 17 22 +22 22 -22 se3 b 1.1 1.2 1.3 1.4 1.5 3.1 4.1 4.2 4.3 4.4 5.1 5.2 5.3 5.4 5.5 FIGURES Actual and Forecasted Fuel Oil Prices in the Juneau Area 1977-1990 . . . . . Actual and Forecasted Wholesale and Residential Electricity Price in the Juneau Area 1977-1990 . Heating Energy Cost of Electricity and Fuel Oil Adjusted for End Use Efficiency for the Juneau Area, 1977-1990, Assuming an 8% Rate of Inflation Comparative COPs and Heating Requirements for ASHPs and WSHPs as a Function of Exterior Temperature . Typical Ground Water Source Heat Pump Installation Price-Capacity Relationship for Water Source Heat Pumps 7 ‘ . . . . . . Observed Water Temperature (°C) at Selected Depths in Auke Bay, Alaska, 1960-68 . : . Observed Salinities (9/00) at Selected Depths in Auke Bay, Alaska, 1960-68 . 7 . Typical Profiles of Temperature (°C) in Auke Bay, Alaska, for cane y. April, duly. and October 1960-68 7 . . . Typical Profiles of Salinity (9/00) in Auke Bay, Alaska, for January, — duly. and October 1960-68 . . Floor Plan for Typical New Residential Construction in the Mendenhall Valley : . . . . Floor Plan for Filter Building at Auke Bay Laboratory . : . . . : . . Floor Plan for First Floor of Warehouse on Juneau Waterfront . . . . Floor Plan for Mezzanine of Warehouse on Juneau Waterfront . . . etc . Floor Plan for West End of Snettisham Salmon Hatchery . . . . . . . 1.2 1.5 1.6 1.8 1.10 3.6 4.10 4.11 4.12 4.13 5.3 5.4 5.6 5.6 5.8 5.6 Floor Plan for East End of Snettisham Salmon Hatchery. . . . 7 . 5 7 : : 5.8 6.1 Coefficient of Performance and Heating Capacity Versus Inlet Water Temperature for Example WSHP . \ . $ 6.18 vi 1.1 1.2 2.1 2.2 3.1 3.2 4.1 5.1 5.2 5.3 5.4 5.5 6.1 6.2 6.3 6.4 6.5 TABLES Percent of Total Energy Consumption by Sector in the Juneau-Douglas Area in 1977 7 7 . Current Residential Rates for Alaska Electrical Light and Power Company (AEL&P) and Glacier Highway Electrical Association (GHEA) 7 . 4 , Summary of Levelized Life Cycle Costs for Alternative Heating Methods . ° . . Annual Oil and Electricity Consumption for Alternative Heating Methods . 7 . 7 7 Summary of Water-to-Air Heat Pumps . : Summary of Commercial Size Water-to-Air Heat Pumps Suggested Limiting Design Velocities for Copper Alloys in Sea Water Piping Systems . . . Summary of Assumptions and Results of Heat Load Calculations A ‘ : : Cost Estimate, Mendenhall Valley Residence . : Cost Estimate, Auke Bay Filter Building 7 . Cost Estimate, Subport Warehouse . . 7 le. Cost Estimate, Snettisham Salmon Hatchery . . Discount and Escalation Rates Assuming an 8% Rate of General Inflation . : : . . Annual Heating Requirement for Structures Evaluated 7 . : fs Season System Efficiencies/COPs for Residential Heating Systems . . : A 7 . . O&M Labor Requirements for Residential Heating Systems, 1981-1990 (man-hr) . 7 7 WSHP Heating System Purchase and Installation Costs and Equivalent Annual Investment Costs - Mendenhall Valley Residence . . 7 7 7 vii 1.1 1.4 2.1 2.2 3.3 3.4 4.15 5.9 5.13 5.15 5.18 5.21 6.2 6.3 6.5 6.6 6.7 6.6 6.7 6.8 6.9 6.10 6.11 6.12 6.13 6.14 6.15 6.16 Purchase Price and Annual Equivalent Investment Cost for Alternative Heating Systems for Mendenhall Valley Residence : . . Levelized Costs for Alternative Heating Methods - Mendenhall Valley Residence . i: . 7 , Heating System Purchase and Installation Costs and Equivalent Annual Investment Costs - Filter Building . Levelized Annual Costs for Alternative Heating Methods - Filter Building 7 : 0&M Labor Requirements for the Warehouse Heating Systems, 1981-1990 (man-hr) . 7 7 7 ‘ ‘ Heating System Purchase and Installation Costs and Equivalent Annual Investment Costs - Warehouse. Levelized Annual Costs for Alternate Heating Methods - Warehouse ° O&M Labor Requirements for the Salmon Hatchery Heating Systems, 1981-1990 (man-hr) Heating System Purchase and Installation Costs and Equivalent Annual Investment Costs - Salmon Hatchery . Levelized Annual Costs for Alternative Heating Methods - Salmon Hatchery . 7 7 Annual Oil and Electricity Consumption for Alternative Heating Methods . . : 7 7 7 7 7 viii 6.8 6.8 6.10 6.11 6.13 6.14 6.14 6.15 6.16 6.17 6.23 PREFACE AND ACKNOWLEDGMENTS This report presents the findings of an analysis conducted by Battelle- Pacific Northwest Laboratories for the Alaska Power Administration. The analysis benefitted greatly from contributions supplied by a number of people throughout both the state and the nation. In particular, we would like to acknowledge the following organizations and people: Alaska Power Administration Bob Cross Floyd Summers Alaska Electric Light and Power Company Bill Corbus Don Jondah1 Jim Webb Alaskan Refrigeration Mike Tennison McConaghy Construction Jim McConaghy Howard's Refrigeration and Heating Dave Howard Jack's Plumbing and Heating Mel Dehart Gary Dunne Winters Electric Steve Winters National Marine Fisheries Service John H. Kinney City and Borough of Juneau John Spietz Vernon Akin & Associates Vern Akin ix The authors hope this evaluation proves of value to the Alaska Power Administration and the residents of Juneau and southeast Alaska. We welcome comments, questions, and criticisms. J. Jacobsen, Project Manager . C. King L. Eisenhauer I. Gibson 1.0 INTRODUCTION Fuel oil is the predominant source of energy in the Juneau area. Fuel oil accounted for approximately 46 percent of the energy consumed in the Juneau area in 1977. As shown in Table 1.1, the majority of this (33 percent of the total) was used by the residential sector, while the remainder (12.5 percent of the total) was consumed by the commercial, industrial, and government sectors. The primary uses for fuel oi] are space and water heating (AEA 1979, p. 5). It is estimated that over 97 percent of the residences in the Juneau area use oil as the primary source of space and water heat ing. (2) Increases in the price of fuel oi] during the past year have resulted in greatly increased heating bills for residents of Juneau for both homes and businesses. During the past year, the price of fuel oil in 500 gallon quanti- ties has increased from about $0.73 per gallon (April 1979) to $0.93 per gal- lon (April 1980). During the past three years, the price has increased by over 100 percent (from about $0.46 to about $0.93 per gallon). (4) These Prices are shown graphically in Figure 1.1. TABLE 1.1. Percent of Total Energy Consumption by Sector in the Juneau-Douglas Area in 1977 (Percent) Gasoline Elec- Diesel, & Aviation & Sector Fuel 0i1 tricity Propane Jet Fuel Total Residential 33.4 4.6 - - 38.0 Commercial, 12.5 6.4 0.9 - 19.8 Industrial, & Government Transportation - 30.7 10.4 41.2 Total 45.9 11.4 31.6 10.4 100.0 Source: AEA 1979, p. 9. (a) Discussions with the APA personnel, April 7, 1980. 1.1 —-— 9%ANNUAL INCREASE (6% INFLATION) 11% ANNUAL INCREASE (8% INFLATION) ——— 13%ANNUAL INCREASE (10% INFLATION) FUEL OIL PRICE ($/ GALLON) 1977 1980 1985 1990 FIGURE 1.1. Actual and Forecasted Fuel Oil Prices in the Juneau Area 1977-1990 Recent history has shown that making accurate long-term forecasts of the price of petroleum is fraught with difficulty. However, it is necessary to make assumptions regarding future prices in order to compare future energy and home heating costs. A recent study suggests that future long-term increases in petroleum product prices will be approximately 3 percent above the rate of inflation (Swift et al. 1979, p. 7.16). While this incremental rate of increase may be conservative based upon the experience of recent years it appears to be a reasonable assumption over the 1980-1990 time period. Assum- ing a long-term rate of inflation of 8 percent per year would then indicate an increase of 11 percent per year in the price of fuel oil. The future price of fuel oil, assuming an 6, 8, and 10 percent rate of inflation in the future, is shown in Figure 1.1. 1.2 These increases in fuel oil translate directly into similar percentage increases in the cost of space and water heating using fuel oi]. Because of these relatively rapid price increases, there is widespread interest in the Juneau area in finding alternative energy sources and/or technologies that will reduce the cost of space and water heating. In addition to reducing the cost of heating, however, alternative sources of energy should be convenient to use, available to the consumer, and available in adequate supply, both now and in the future. One alternative energy source which now appears to meet these criteria in most cases is electricity. Electricity is one of the most convenient energy sources and is available to most residential, commercial, and industrial users in the Juneau area. (4) In addition, there is presently excess hydroelectric generating capacity in the Juneau area and there appears to be adequate hydro- power sites in the area to supply a large-scale conversion to electric home heating (CH2M Hill 1980, pp. 1-2). Historically, the relative price of fuel oi] versus electricity has favored the use of fuel oil for heating in the Juneau area. However, recent price increases have reversed that situation in some cases. Also, it does not appear that the price of electricity will increase as rapidly as the price of fuel oi] in the future. The primary supplier of electricity in the Juneau area is the Alaska Power Administration's (APA) Snettisham hydroelectric facility. The APA presently markets power in the Juneau area at a wholesale rate of $0.0156 per kWh. This price is not expected to increase until 1985. While the extent of the price increase in 1985 is not known at this time, an increase to $0.025 per kWh would seem reasonable. (>) The present residen- tial rates for electricity for the Glacier Highway Electric Association (GHEA) and the Alaska Electric Light and Power Company (AEL&P) are shown in Table 1.2. These prices are presented graphically in Figure 1.2 (over 180 kWh for AEL&P and over 750 kWh for GHEA). (a) In most cases, the electrical service to buildings would have to be increased and in some cases, the capacity of the electrical distribution system may have to be increased. (b) Discussions with APA personnel, April 7, 1980. 1.3 TABLE 1.2. Current Residential Rates for Alaska Electrical Light and Power Company (AEL&P) and Glacier Highway Electrical Association (GHEA) AEL&P GHEA (Without electric water (All Users) heater or space heat) First 250 kWh--12.3¢ First 200 kWh--5.8¢ Next 250 kWh-- 9.6¢ Over 200 kWh--4.4¢ Next 250 kWh-- 7.7¢ + $5.00 min. charge Over 750 kWh-- 4.7¢ (With electric water heater without electric space heat) First 180 kWh--5.8¢ Over 180 kWh--3.6¢ + $5.00 min. charge (With both electric water heater and space heat) First 180 kWh--5.8¢ Over 180 kWh--3.6¢ + $7.00 min. charge Source: Current rates information AEL&P and GHEA, April 1980. It is doubtful that the operating costs of these utilities will increase as fast as the price of fuel oil in the future. Present estimates indicate that Juneau area utility costs and, therefore, the utility portion of the residential price of electricity will increase at approximately one-half the rate of inflation (i.e., assuming a 8% rate of inflation electrical prices would increase at about ay) . (2) As shown in Figure 1.3, at present prices the cost of energy for electri- cal resistance heating and heating using fuel oil are very close. Assuming (a) Battelle estimates based on conversation with William A. Corbus, manager AEL&P, April 9, 1980. 1.4 ——+—— 3% ANNUAL INCREASE (6% INFLATION) 4% ANNUAL INCREASE (8% INFLATION) mmm SR ANNUAL INCREASE (10% INFLATION) ELECTRICITY PRICE (¢/kW H) f APA WHOLESALE RATE 1977 1980 1985 1990 FIGURE 1.2. Actual and Forecasted Wholesale and Residential Electricity Price in the Juneau Area 1977-1990 that the heating is done with a heat pump with an annual coefficient of perfor- mance (cop) (@) of 2.0, electricity has a lower energy cost than fuel oil at the present time, (>) It is important to note that the relative costs of electricity and fuel oil for heating shown in Figure 1.3 are strongly dependent on the assumed rate of inflation. The higher the rate of inflation the more attractive electric heating becomes. At low rates of inflation energy costs for fuel oil heating will remain lower than the energy costs for heating using electrical resis- tance for a longer period of time. (a) The Coefficient of Performance (COP) is a ratio calculated by dividing heating capacity in watts by power input in watts. (b) The costs shown in Figure 1.3 include only energy. The costs of neither the heating system (oi] furnace, hydronic baseboard units, electrical resistance units, etc.) nor the operating costs are included. Total heat- ing costs are discussed and computed in Chapter 6. 1.5 —— FUEL OIL ASSUMING 136, 690 BTU/ GALLON & 55% HEATING EFFICIENCY —— AEL&P ASSUMING 100% ELECTRICAL HEATING EFFICIENCY ==-= AEL&P ASSUMING 200% ELECTRICAL HEATING EFFICIENCY (HEAT PUMP COP OF 2.0) —-—— = GHEA ASSUMING 100% ELECTRICAL HEATING EFFICIENCY 40 35 sesseeeee — GHEA ASSUMING 200% ELECTRICAL HEATING EFFICIENCY HEATING ENERGY COSTS ($/MILLION BTU) 1977 1980 1985 1990 FIGURE 1.3. Heating Energy Cost of Electricity and Fuel Oil Adjusted for End Use Efficiency for the Juneau Area, 1977-1990, Assuming an 8% Rate of Inflation The APA, AEL&P, and GHEA have investigated the costs of several of the alternatives available for using electricity for space heating (AEA 1979 and CH2M Hill 1980). In these studies, the costs of heating using electrical resistance baseboard units and air source heat pumps (ASHPs) have been com- puted and compared to the costs of heating using fuel oi] fired hydronic sys- tems. Generally, the costs of heating using ASHPs are significantly lower and electric resistance baseboard heating marginally lower than for oi]l-hydronic systems depending upon the assumptions made regarding electricity and fuel oil prices (CH2M Hill 1980, p. 9). At the present time, the APA, AEL&P, and GHEA are sponsoring an ASHP field demonstration project. 1.6 The APA, in a continuing effort to investigate economic and efficient alternatives that will reduce fuel oil consumption by conversions to renewable hydroelectric power, has sponsored the preparation of this report evaluating the use of water source heat pumps (WSHPs) for residential, commercial, and industrial heating in the Juneau area. Heat pumps are the most efficient state-of-the-art heating system currently available. In principle, a WSHP operates exactly like an ASHP, transferring heat from a low temperature source to a higher temperature sink. In the case of an ASHP, heat would be transferred from the outside air (the low temperature source) to the inside air (the higher temperature sink). In the case of a WSHP, the source of the heat is water. In this analysis, three possible sources of water are evaluated: ground water, sea water, and lake water. There are several advantages of WSHPs as compared to ASHPs. One advan- tage stems from the fact that WSHPs operate at a constant COP, regardless of the outside air temperature. Since WSHPs use ground water or sea water, rather than the outside air, as a heat source and since ground and sea water remain at almost a constant temperature all year, WSHPs operate at a constant COP. The COPs for typical ASHPs and WSHPs as a function of outside air temperature are shown in Figure 1.4. As shown in Figure 1.4, the COP of ASHPs decreases as the outside air (the heat source) goes down, while the COP of WSHPs remains con- stant. Unfortunately, as the outside air temperature goes down, the heat load increases. As also shown in Figure 1.4, the heating load is inversely propor- tional to the outside air temperature. The shaded areas A and B represent the heating load for a typical structure. The shaded area B represents the supple- mental heating (typically electrical resistance) required for a ASHP installa- tion. However, WSHP installations are typically designed to provide the full heating required at the design heating load, thus, eliminating the need for supplemental heating. The elimination of the need for electrical supplemental heating is a benefit to both the consumer and the electrical utility. The con- sumer benefits since less relatively expensive electrical resistance heating is required and the utility benefits because the peak demand during periods of low temperature is reduced, thus, reducing the peak generating and distribution capacity required. 1.7 AIR SOURCE HEAT PUMP COP a oO : { 5 _ ua a ae = WATER SOURCE HEAT PUMP COP e = AT 40° INLET WATER TEMPERATURE Se & SS 2 Bo s = te = a 3S = ° OUTSIDE TEMPERATURE (°F) FIGURE 1.4. Comparative COPs and Heating Requirements for ASHPs and WSHPs as a Function of Exterior Temperature Source: ASHP COP - (AEA 1979, p. 99) WSHP COP - Various manufacturer data sheets and contacts. Includes blower and pump allowance. Another advantage of WSHPs is the fact that WSHPs are typically self- contained. The water supply is typically piped to and from the unit in rela- tively small diameter (1 to 1.5-inch diameter) PVC pipe. There is no external heat exchanger with the associated refrigerant piping and electrical wiring, as is required with an ASHP. Typical WSHPs are about the size and shape of a small refrigerator (28 inches wide x 28 inches deep x 48 inches high). Of course, there are also disadvantages of WSHPs relative to ASHPs. Per- haps the most significant disadvantage is the need to have a water supply and disposal system. In the case of a ground water system, a well, a water pump, water piping, and electrical power is required. Disposal of the effluent water 1.8 can also be a problem, especially during freezing weather. The most common method of disposing of the water is to use a separate return well. For a sea water system, there is still the need for a water supply pump and piping, as well as disposal piping. In addition, the problem of marine fouling in the pipes and heat exchanger must be dealt with in sea water systems. Salt water corrosion, while a problem, can typically be alleviated through the proper selection of materials. Another problem with WSHPs is that at the present time, they are not as common as ASHPs. This means that there are fewer distributors who handle WSHPs and those who do, have less experience regarding installation and maintenance practices. While this situation is changing, nevertheless, it is a factor to include in the decision as to whether to install a WSHP especially in the Juneau area. Figure 1.5 shows a sketch of a typical ground WSHP installation using sep- arate supply and disposal wells. As shown, the heat pump is a single cabinet located inside the building. The cabinet contains a heat exchanger, a compres- sor, an air blower and air heating coils, and the necessary piping, wiring, and controls. Water is supplied to the heat pump from a well and is returned to another disposal well. Of course, if sea water is used there would be no need for either a supply or disposal well. The supply pump would be located either near or in the sea water. The water would be returned to the sea for dis- posal. One option, which is not evaluated in this report, involves locating the refrigerant heat exchanger directly in a body of water such as a lake or the sea. This option eliminates the need for the water supply system but requires longer refrigerant piping runs. In some cases where the building to be heated is located close to the body of water this system may be relatively attractive. The purposes of this project and report are to evaluate the technical and economic viability of WSHPs for use in the Juneau area, and to identify poten- tial demonstration projects to verify their viability. This report is divided into six additional chapters. Chapter 2 presents a brief summary of the results of the project. 1.9 AIR HANDLING UNIT COMPRESSOR HEAT EXCHANGER COIL REFRIGERANT LINES 7, GROUND LINE 77877 DISPOSAL WELL WELL FIGURE 1.5. Typical Ground Water Source Heat Pump Installation The first task undertaken on the project was to contact manufacturers and distributors to identify the specifications, price, and availability of pre- sently available WSHPs. The results of this survey are contained in Chapter 3. Additional information regarding manufacturers and distributors of WSHP equip- ment and WSHPs is contained in Appendix A. , Because of the proximity of Juneau and other southeast Alaska communities to sea water, a brief evaluation was made of the possible use of sea water as a heat source. This evaluation was limited in scope to literature research and conversations with knowledgeable people in the field of sea applications and use. The results of this analysis are contained in Chapter 4. 1.10 To provide a basis for the economic evaluation of WSHPs relative to other types of heating presently used in the Juneau area, four building types and WSHP applications were selected for detailed analysis. A WSHP-based heating system was selected for each of the cases. These buildings and applications were selected to be representative of the current Juneau residential and com- mercial building stock. Once the four cases were chosen, the heat load for each was calculated and a preliminary heating system design developed. The results of the building selection, the heat load calculations, and the heat system design activities, are presented in Chapter 5. Additional details on the heat load calculations are contained in Appendix B and more detailed heating system design information is contained in Appendix C. Chapter 6 presents the results of the evaluations of the four case stud- ies. These evaluations are based upon three major considerations: 1) life cycle costs, 2) technical viability, and 3) effect on fossil and electrical energy use. The object of the technical evaluation is to identify those sys- tems which appear to be most promising from the standpoint of installation, operation, and maintenance. Because of the high cost of fuel oil and the availability of electric power in the Juneau area, the impact of WSHPs on the consumption of these energy sources is analyzed. The life cycle costs for the WSHP-based heating system are compared with the costs of alternative heating systems. The details of the cost analyses are the contents of Appendix D. The final chapter of this report presents recommendations for a program to verify the technical and economic viability of WSHPs in the Juneau area. In this report, there is no analysis of the legal and environmental aspects of WSHP use. In some areas, there may be local restrictions on ground water extraction and disposal, although there do not appear to be any state- wide restrictions. There are state and federal restrictions on the use of sea water. Anyone interested in installing either a ground water source heat pump or a sea water source heat pump should investigate the restrictions and/or per- mits required before proceeding with a detailed design or installation. 1.11 REFERENCES - CHAPTER 1.0 Applied Economics Associates, Inc. March 1979. The Role of Electric Power in the Southeast Alaska Energy Economy. Prepared for the Alaska Power Admini- stration, Juneau, Alaska. CH2M Hill. February 1980. A Comparison of Home Heating Costs: Electricit Versus Oil. Prepared for the Glacter Highway Electric Association, Auke Bay, Alaska. Swift, W. H. et al. March 1978. Alaskan Electric Power - An Analysis of Future Requirements and Supply Alternatives for the Railbelt Re gion. P on. Pre- pared by Pacific Northwest Laboratory, for the Alaska Division nergy and Power Development and the Alaska Power Authority. 1.12 2.0 SUMMARY OF RESULTS e Based upon the cost evaluations described in this report, which are sum- marized in Table 2.1, WSHP heating systems offer life cycle heating costs that are generally comparable or slightly higher than other types of heat- ing available in the Juneau area. For a typical new residence in the Mendenhall Valley a WSHP heating system offers life cycle heating costs that are comparable to electrical resistance heating. An ASHP heating system provides lower heating costs than either electrical resistance or WSHP heating while an oil-hydronic system has the highest costs of all the systems evaluated for the residence. For the Filter Building (a frame building located at the National Marine Fisheries Services Auke Bay Labor- atory) the costs of heating the building using a WSHP system are roughly comparable to the costs of heating the building using a forced air oil furnace. For a warehouse/shop building located on the Juneau waterfront the costs of heating the building using a WSHP system are slightly higher than the costs of heating the building using an oil-hydronic heating sys- tem. In the case of a salmon hatchery located near Snettisham electrical resistance heating is about 8% lower in cost than the WSHP system. TABLE 2.1. Summary of Levelized Life Cycle Costs for Alternative Heating Methods ($) Mendenhall Auke Bay Juneau Snettisham Valley Building Water Front Salmon Heating Method Residence _ Filter Warehouse Hatchery Direct Electrical Resistance 2921 -- -- 9640 Fluid Filled Electrical Resistance 2999 -- -- -- 0i1 Furnace 4495 3208 11,155 -- Air Source Heat Pump 2283 -- -- -- Water Source Heat Pump 3092 3254 13,749 10,516 2.1 Water source heat pumps using either fresh water or sea water are tech- nically viable in the Juneau area. Both sea water and fresh water of acceptable temperature, quality, and quantity are available. It must be kept in mind, however, that in some cases an acceptable water source will not be available. If so, the water supply must be made acceptable or an alternative method of heating selected. The prospective water source must be carefully evaluated on a case-by-case basis early in the planning process. While there are fouling and corrosion problems associated with the use of sea water it appears that these problems can be overcome through proper design and materials selection. Proper installation and maintenance is of paramount importance for WSHPs. Experience suggests that most of the failures and service calls for WSHP installations are related to improperly designed or installed water supply systems or air handling systems. In general, a WSHP itself should be as or more reliable than an ASHP. All WSHP designs and installation should be made by qualified people with a knowledge of WSHP applications. Annual oil and electricity consumption for the alternative heating methods evaluated in this report are presented in Table 2.2. Use of WSHPs for heating in the Juneau area could reduce the use of fossil fuels while increasing the use of electricity. However, the increase in electricity TABLE 2.2. Annual Oil and Electricity Consumption for Alternative Heating Methods Electrical Resistance Oil Heat ASHP WSHP (Electricity) (Fuel 0i1) (Electricity) (Electricity) _ (kWh) _ (gal) ___(kWh) il ea iT Residence 53,875 2412 28,114 23,949 Filter Building -- 1645 -- 15,195 Warehouse -- 4853 -- 60,028 Salmon Hatchery 205 ,033 -- -- 82,013 2.2 use would be relatively low compared to electrical resistance heating since WSHPs offer seasonal COPs from 2.25 to 2.5. The energy consumption estimates for the residence are similar to estimates for Juneau area resi- dences contained in other recent studies (AEA 1979, p. 99 and CH2M Hill 1980, Appendix Table 8). However, these estimates are higher than the average "all electric" residential consumption of 24,216 kWh derived from 1977 electrical consumption data for the Juneau area (AEA 1979, p. 14). There are several possible reasons for this difference. They include dif- ferences between the design interior temperature (70°F) and the tempera- tures maintained in actual practice, possible use of supplemental heating in existing residences, differences in the size and location of the resi- dences, and differences in insulation. These reasons are discussed in more detail in Section 6.4. During the survey of heat pump manufacturers and data collection efforts, 19 manufacturers of WSHPs were contacted. Twelve of them have Northwest distributors in the Seattle, Portland, or Spokane areas. All made resi- dential sized units (to 100,000 Btu/hr) and 8 made commercial sized units (over 100,000 Btu/hr). Several manufacturers offer standard units which operate on water in the 38 to 45°F temperature range that is common in the Juneau area. Because of the relatively low water temperatures, possible fouling and corrosion problems associated with the use of sea water, and uncertain- ties about the availability of proper design and maintenance in Juneau, a field demonstration program to verify the results of this report should be conducted before a final recommendation is made as to the viability of WSHPs in the Juneau area. 2.3 REFERENCES - CHAPTER 2.0 Applied Economics Associates, Inc. March 1979. The Role of Electric Power in the Southeast Alaska Energy Economy. Prepared for the Alaska Power Admini- stration, Juneau, Alaska. CH2M Hill. February 1980. A comparison of Home Heating Costs: Electricity Versus Oil. Prepared for the Glacier Highway Electric Association, Auke Bay, Alaska. 2.4 3.0 SURVEY OF WATER SOURCE HEAT PUMP MANUFACTURERS SEE UANUPFACTURERS An intricate portion of the evaluation of water source heat pump potential for southeast Alaska was an investigation of existing manufacturers of water- to-air heat pumps. While air-to-air heat pumps are widely manufactured and used in many parts of the U.S., water-to-air and water-to-water heat pumps are less abundant. Three principle sources were used to obtain a comprehensive list of heat pump manufacturers: Directory of Certified Applied Air Conditioning Products (ARI 1979), Heat Pump Manufacturers List from the National Water Well Associa- tion (NWWA 1980), and the Portland and Seattle Yellow Pages. After a master list was compiled the manufacturers and distributors were contacted by phone. A complete listing of water source heat pump manufacturers and distributors with their addresses is included in Appendix A of this report. Of the 45 heat pump manufacturers and distributors contacted, approxi- mately half made water source heat pumps. These manufacturers fell into two general categories: large heating and air conditioning companies that carried a line of water source heat pumps and small companies that specialized in heat pumps or solar/heat pump systems. Most of the manufacturers that produce water source heat pumps produce only water-to-air or air-to-air systems. Three companies produce water-to- water systems, six companies produce solar assisted systems, one company uses a closed-loop circulating refrigerant system, and one company uses heatmats to collect heat from water or ground sources. Existing water-to-water heat pumps are limited in their application for residential space heating because of the relatively low heated water tempera- tures they produce. In most cases the heated water is in the 120 to 140°F range. Water at these temperatures is not suitable for use in conventional fan coil or baseboard heating units. Such units require water temperatures in the 170 to 190°F range. Existing water-to-water units are suitable for radiant heating applications such as systems where water pipes are embedded in the floor. 3.1 Most water-to-air heat pump manufacturers produce several models for vari- ous heating capacity requirements. All manufacturers in the survey produced residential size units (10,000-100,000 BtuH(@)) and eight produced commer- cial size units (over 100,000 BtuH). A summary of water-to-air heat pump manufacturers, heating capacity, and northwest distributors is presented in Table 3.1. It is important to note that manufacturers use different methods to rate heating capacity. Heating capacity is a function of water flow rate, indoor air temperature, and entering water temperature. Therefore, heating capacity ratings from different manufacturers may not be comparable unless these vari- ables are specified. Twelve of the nineteen brands of water-to-air heat pumps have Northwest distributors in the Seattle, Portland, or Spokane areas. Brands without North- west distributors tended to be the newer companies. Most of the Northwest dis- tributors believed they could supply their brand of heat pump with little or no delay. Some, however, expressed concern over proper installation and ser- viceability of their units in southeastern Alaska. Eight companies produce commercial size water-to-air units; five of these companies have Northwest distributors. A summary of commercial size water-to- air heat pumps is listed in Table 3.2. In most cases the commercial sized units are not suitable for low inlet water temperature applications. These units are typically designed for large commercial applications utilizing a water boiler and including waste heat recovery systems. They are designed for inlet water temperatures in the range of 60 to 90°F. At the present time it appears that the best way to heat larger buildings using low temperature water is to use multiple residential sized units designed specifically for low water temperature applications. Prices of heat pumps varied significantly depending on system options. Some prices reflect the basic heat pump unit while others include control sys- tems. Prices also varied depending on the type of electrical service (one or (a) Two abbreviations for British Thermal Units per hour are used in this report, BtuH and Btu/hr. 3.2 TABLE 3.1. Summary of Water-to-Air Heat Pumps Company Brand Mode1s(#)(®) _Northwest Distributor American Air Filter EnerCon 9 Models -- 10,000-62,000 BtuH Carrier Carrier 6 Models Airefco Inc. Command-Aire Conservation Technology » Florida Heat Pump Friedrich Heat Controller Heat Exchanger International Energy Conservation Systems Inc. Mammoth Northrup, Inc. Phoenix Singer "Solar Oriented" Environmental Systems Inc. Thermal Energy Transfer Company Vanguard Energy Systems Wescorp Whalen York (a) Heating capacity is a function of water flow rate (GPM), air flow rate (CFM), and entering water temperature (OF). different values for these factors and their h those of other manufacturers. heating capacity. was chosen, Command-Aire Convectionaire Energy Miser Friedrich- Climate Master Century/Comfort Aire KoldWave TempMaster Hydrobank Northrup Enviro-Temp Singer SOESI/SERCO TETCO Vanguard Solargy Whalen York In many cases t 14,000-42,000 BtuH 16 Models 12,000-350,000 BtuH 5 Models 13,000-41,000 BtuH 14 Models 13,000-240,000 BtuH 4 Models 41,000-61,000 BtuH 17 Models 25 ,000-410,000 BtuH 12 Models 11,000-250,000 BtuH 16 Models 15,000-400,000 BtuH 31 Models 10,000-930,000 BtuH 9 Models 10,000-71,000 BtuH 5 Models 33,000-95,000 BtuH 6 Models 18,000-58,000 BtuH 11 Models 18,000-244,000 BtuH 2 Models 40,000-52,000 BtuH 5 Models 27 ,000-72,000 BtuH 10 Models 15,000-104,000 BtuH 4 Models 26 ,000-72,000 BtuH 3 Models 23,000-45,000 BtuH (b) Heating capacities are rounded to the nearest 1000 BtuH. 3.3 Brod and McClung-Pace Co. Peerless Pacific Airtec Hardesty Pameco-Aire Enviro Air Systems Hal Teasley and Associates, Inc. Hal Teasley and Associates, Inc. Pitcher Pump Brod and McClung-Pace Co. R. D. Morse Company Day-York indoor air temperature (°F), Many manufacturers use eating capacity may not be comparable with he manufacturer supplied a single value of When several values were given, the one closest to the ARI standards bre Northwest Distributor TABLE 3.2. Summary of Commercial Size Water-to-Air Heat Pumps Company Brand Mode1s (4) (>) Command-Aire Command-Aire 7 Models Florida Heat Pump Heat Controller Heat Exchangers Inc. International Energy Conservation Systems Inc. Mammoth "Solar Oriented" Environmental Systems Inc. Wescorp Energy Miser Comfort-Aire KoldWave TempMaster Hydrobank SOESI/SERCO Solargy 101,000-338,000 BtuH 4 Models 107 ,000-262,000 BtuH 6 Models 105 ,000-410,000 BtuH 4 Models 108 ,000-249 ,000 BtuH 7 Models 104,000-400,000 BtuH 23 Models 115,000-930,000 BtuH 5 Models 106 ,000-244 ,000 BtuH 1 Model 104,000 BtuH Brod and McClung-Pace Co. Peerless Pacific Hardesty Pameco-Aire Enviro Air Systems Brod and McClung-Pace Co. (a) Heating capacity is a function of water flow rate (GPM), indoor air temperature (°F), air flow rate (CFM), and entering water temperature (°F). Many manufacturers use different values for these factors and their heating capacity may not be comparable with those of other manufacturers. heating capacity. was chosen. (b) Heating capacities are rounded to the nearest 1000 BtuH. In many cases the manufacturer supplied a single value of When several values were given, the one closest to the ARI standards three phase) and the physical characteristics of the unit (horizontal or verti- cal). A price-capacity curve is shown in Figure 3.1. A complete listing of prices by capacity and brand is included in Appendix A. Eight brands (Century, KoldWave, Vanguard, TETCO, Solargy, Carrier, Friedrich, and Enviro-Temp) reported that they operate in the 40°-45°F enter- ing water temperature range. Other brands may also operate in this range by altering their water flow rate but did not specifically state so in their brochures. Several distributors indicated that their heat pumps can accept low temperature water if appropriate adjustments are made to the system. This may include adjusting water flow rates or adding system options to heat pump packages. In summary, it appears that there are several brands of water-to-air heat pumps that are applicable to the climate and structure size encountered in southeast Alaska. Most manufacturers supply a variety of sizes and have dis- tributors in the Pacific Northwest. 3.5 HEAT PUMP COST ($1000) 50 FIGURE 3.1. 100 150 200 250 300 350 HEATING CAPACITY (1000 BTU H) Price-Capacity Relationship for Water Source Heat Pumps (Spring 1980 Price Levels) 3.6 REFERENCES - CHAPTER 3.0 Air-Conditioning and Refrigeration Institute. 1979. Directory of Certified Applied Air-Conditioning Products, December 1, 1979 - May 31, ; Arlington, Virginia. Christian, J. E. 1977. Unitary Water-to-Air Heat Pumps. ANL/CES/TE 77-9. Prepared for Argonne National Laboratory by Oak Ridge National Laboratory, Oak Ridge, Tennessee. Hildebrandt, A. F. and F. R. Elliott. 1979. Ground Water Heat Pump HVAC Demonstration Project Phase 1 - Design Development. EDF-OlF. Prepared for the Texas Energy A T re dvisory Council, ouston, Texas. National Water Well Association. 1980. "Heat Pump Manufacturers." Obtained at The National Ground Water Geothermal Heat Pump Conference and Ex osition, February 11-12, 1980, Ohio State University, Columbus, Ohio. 3.7 4.0 ASSESSMENT OF FOULING AND CORROSION PROBLEMS - RELATED TO USE OF SEA WATER AS A HEAT SOURCE Fouling and corrosion are the two most serious problems related to the use of sea water as a heat source in WSHPs. Each of these problems and meth- ods of overcoming them are discussed in this chapter. The annual temperatures and temperature variation of sea water in the Juneau area is also briefly discussed. 4.1 ASSESSMENT OF FOULING PROBLEMS One of the problems in using sea water as a heat source in a heat pump system is the fouling (growth of marine organisms) that can occur on any sur- face exposed to marine water. Within marine water are a large number of larval forms that are able to pass through most screens and/or pumps and eventually settle out and grow into large adult forms which can clog a circulating water system and/or create an effective barrier to good heat exchange across sur- faces. This problem is common to heat exchanger systems that use marine waters. The problem has been solved in large heat exchange systems, such as those used at steam electric stations, by several methods; the main one being the removal of the fouling growth at intervals by use of a biocide, heat treatment, and/or mechanical scrubbing. The most common method is the use of chlorine. Basically, there are three ways to prevent/control fouling: exclu- sion of the organism, prevention of attachment, or cleaning of the surfaces after the fouling organisms have attached. All three methods are now being employed under different situations, and the one that is used is determined by system design needs, cost, and environmental constraints. The exclusion method is probably the least frequently used procedure for the prevention of fouling in circulating sea water systems. It is used where the volume of water needed is not high and there is an availability of sandy substrate. The general configuration is for the intake line to be located under the sand sub- strate and the water drawn through the sand; thereby filtering the organisms out of the water as it percolates through the sand. In the prevention method, the surface is coated with some type of toxic substance which inhibits the attachment of fouling, or a toxic material is added to the sea water to reduce 4.1 the ability of organisms to attach. Under certain conditions, setting may be prevented by high water velocities. The Europeans, particularly in England, are using continuous low-level chlorination to prevent the attachment of mus- sels and some foulers in their power plants that use sea water. Antifouling toxic coatings are also used; the toxicant gradually leaches from a surface and prevents the organisms from setting. Because of the leaching process, there is a finite life to the toxic material within the system and; therefore, it eventually becomes noneffective, and fouling occurs. The best example of this method is the antifouling paint used on boat bottoms. A system that is somewhat similar to this is the use of metals that are toxic to marine orga- nisms in high concentrations. Examples of this are the use of copper or copper/nickel alloys. With these, the surface remains clean for a significant period of time but, eventually, there is sufficient nontoxic material built up on the surface so that fouling occurs. The primary early foulers are phyto- plankters and bacteria which form coatings that allow larger foulers to be isolated from the metallic surface. Physical cleaning of the surface is commonly used where the fouling of the surface does not create a significant problem for the operation of a system, or where routine "down-time" and physical cleaning costs can be tolerated. In addition, there are two on-line mechanical methods now used for condenser cleaning in large steam electric stations; one is a Mann® brush and the other is an Amertap® system. In both of these systems, a projectile is sent through the tubes periodically to physically remove any fouling that has occurred. Although these methods do keep the heat exchanger tubes clean, the piping lead- ing to and from the heat exchanger is still able to foul and, therefore, it is necessary to physically or chemically clean these surfaces recurrently. Another method of cleaning is chemical. In this situation, fouling is allowed to occur and develop up to a certain point, and then chlorine or another biocide is added to the system to kill the fouling and have it slough off. This method works well if the fouling consists of organic matter, phyto- plankters or soft fouling organisms with loose attachments; however, if the foulers are organisms such as barnacles, mussels and other encrusting type animals, the chlorine will kill them, but their shell will remain attached to 4.2 the surface and continue to inhibit water flow and/or heat exchange efficiency. The general way to operate with a biocide is to periodically clean to prevent these hard foulers from growing to any size or becoming firmly attached. In addition to the proactive prevention or cleaning methods that can be used to keep the surfaces clean, there are a number of natural phenomena that may, in fact, help inhibit or remove fouling organisms from any particular sub- strate in a heat exchange system. These include: periodic incursion of water of a salinity not tolerated by the organisms, thereby causing them to die; the periodic increase in temperature above the normal living range of the orga- nisms; the periodic reduction of oxygen concentration to a point below which the animals can live; or operation of the system only during those periods of time when the larvae are not present in the water column and, therefore, not available to settle and grow on the system surfaces. For fouling considerations there are two basic heat exchanger concepts. One is where the sea water is pumped from a source through a heat exchanger and then returned to the source. The other is where the heat exchanger is placed in the sea water, and the circulating fluid is something other than sea water. In the first case, you would have the potential for fouling in the pip- ing and plumbing that leads to the heat exchanger and on the sea water side of the heat exchanger. In the second case, the fouling would be on the outer surface of a heat exchanger. In the former case, there are generally larger and more complicated surfaces to keep clean, but it is easier to control the environment within which the surfaces exist. In the latter case, there is a less complicated and smaller surface area for fouling, but it is difficult to control the environment of the surface. In the case of circulating sea water to a heat exchanger and back to the bay, all three preventive methods are available. The organisms can be excluded and prevented from settling and/or periodically cleaned off. If desired, a combination of all three may be used, depending on the biological situation and a number of chemical and physical characteristics of the water used in the system. For example, if a porous, fine-grained sediment is available at a depth that would provide water of the correct temperature, then a subsand fil- ter intake could be used. The sea water being pumped through the system would 4.3 be relatively free of organisms and very little fouling would be expected. However, even under these situations there may be some bacteria and/or slime molds that could grow in the system and, therefore, periodic cleaning with a biocide or by mechanical means would be advisable. With the circulating sea water system, a second possibility is to use a coarse screened intake to prevent larger organisms from entering the piping system and clogging the pumps or small orifices that may exist within the plumbing. With this system, continuous or periodic chlorination is needed as required by loss of heat exchange efficiency. Under this system there are hazards to periodic chlorination. Organisms could enter, set, and grow to a size where, even though they are killed by chlorination, there are hard parts left within the system which may create problems. However, the exact situ- ation as to abundance of organisms, physical/chemical characteristics of the water and variability of the physical/chemical condition may reduce the poten- tial for fouling very significantly during the season when the heat pump would be used. With this latter circulating system, a number of preventative and/or ¢leaning methods would be available. They would include periodic chlorination or chlorination at a low level throughout specific time periods; placing the system where low salinity or fresh water is pumped through it in the spring, 'thereby killing marine organisms that have set over the winter months; or by shutting the system down and sealing it off during the summer to allow the contained water to become anoxic, thereby killing everything. The implemen- tation of this system would be highly dependent on what the fouling scheme was for the particular area being used. Preliminary survey of the data available on meroplankton from the Juneau area indicates that most of the hard fouler larvae are present in the water from April through June (Wing and Reid 1972). Therefore, the fouling problem during the remainder of the year could be reduced to bacteria and/or some occa- sional soft foulers that are present. Considering the general temperature of the water throughout most of the year is less than 8°C, the growth rate of these organisms may be very limited. The cleaning problem, therefore, may be very minimal and/or sporadic and hard to predict accurately. Under this 4.4 system, the following scenario could occur. The system is installed with a quarter-inch mesh screened intake, and water is pumped into a heat exchanger and then returned to the bay. The system is started up in late September or early October and runs for an entire winter. Based on the available informa- tion, very little fouling would occur and no antifouling measures would need to be taken. The system is shut down in early June and the water in the sys- tem allowed to become anoxic. Organisms that have settled in the system die, and when it is turned on the next October, the anoxic water is flushed out and the system is clean. Another aid in maintaining the cleanliness of the system is its composition of copper/nickel alloy. The shutting down of the system and allowing it to go anoxic would regenerate the surfaces where free copper would be available. Care would have to be taken to insure that when the sys- tem is anoxic there are not conditions that would allow a galvanic cell to be established and cause acceleration of corrosion. In the second year of running, everything goes well again, and there is no major fouling; heat exchanger efficiency stays up, and there is no pumping problem. The only activity that may have to be undertaken would be the annual cleaning of the intake screen to make sure that fouling organisms have not set- tled on it and blocked its surface area, thereby reducing pumping ability. In the third year, there is a late spawn of the barnacles or mussels, and an early cold spell causes an earlier than normal startup of the heat pump, providing a situation where larvae are available for setting. Being unaware that these organisms are present, no precautions are taken and they set within the system and grow to a fairly good size throughout the winter. When the system is turned off the following spring and allowed to go anoxic (providing it was able to maintain itself throughout the year), these organisms would die. However, normally the barnacle tests will stay attached because of their gluing mecha- nisms, and the mussel shells will float free in the system. When a system is started up the following year, the barnacle shells there would inhibit heat exchange, reduce the flow and the pipe diameter. The shell debris from the mussels would be in the system and possibly clog the heat exchanger. There- fore, with this system, although one or more years of good operation may occur, the potential for nonfunction or becoming fouled at some point in time is 4.5 appears that a 10% trade solution is the most economical. For the Seattle area, 15% "trade percent available Cl," costs $17.45/case of 6 gallons. However, this normally decays to a 10-11% solution on the shelf so, unless measurements of the actual quantities of Cl, (as HOC] ) are made period- ically for calculations of required delivery rates, one would need to assume a 10% solution to be on the conservative side. For example, a system that uses 100 gpm of sea water would require the 10% sodium hypochlorite solution to be added at a rate of 0.002 gal/min to accom- plish a residual oxidant of 1.0 ppm. This calculates out to be approximately 0.14 gal/hr or, on the three times a day for one hour schedule, 140 gal/yr. This figure is conservative and could be reduced by a number of factors: lower dose rate required because of natural demand, less frequent dosing, or higher Cl, concentration in stock solution. Chlorination units capable of deliver- ing the chlorine are made by a number of manufacturers. Continuous dosing at 0.5 ppm residual would require the addition of approximately 2 ppm Cl, and, thus, use the same sodium hypochlorite solution at a rate of 0.0015 gal/min or 0.09 gal/hr. For a three-month period this would require 194 gallons of solution. The discharging of residual Cl, or other oxidants is regulated by EPA. However, their current regulation is vague about where the residual is to be measured. If it is in the discharge pipe, the described system would not be legal without a special exemption. However, if an area of mixing is allowed, then the natural demand of the sea water in the discharge area would probably remove any residual Cl, and bring the system within the EPA guidelines of 2.0 ug/1 for salmonoid fish and 10.0 ug/l for other freshwater and marine organisms (U.S. Environmental Protection Agency 1976). However, applicable state laws and regulations would need to be reviewed to assure compliance. The use of a sand filter is also an attractive method for elimination of fouling organisms. In this type of system a swimming pool type sand filter or a subsand intake structure is used to prevent most fouling organisms from entering the piping system. The use of a subsand intake would be dependent on the local sediment conditions. The use of a swimming pool type filter would 4.8 have an initial cost of approximately $500 to $1,000, depending on the expected particulate load in the water and the volume of water required for the system. In addition to the filter, the pump would need to be strong enough to provide sufficient water with the head loss caused by the filter. Filter systems require routine backflushing and periodic maintenance to clear foulers from the sea water side of the filter. The rate of backflushing is dependent on the sea water's particulate load and can vary from minutes to months. The backflushing can be manual or automated. In addition, the capa- bility for slug chlorination should be included in the system to allow for periodic removal of slimes. There iS a limited amount of published temperature and salinity data available for the waters of interest to the project. The most complete and detailed information is for Auke Bay (Bruce et al. 1977). This report provides a summary of selected physical and chemical characteristics of Auke Bay for the period 1961-1968. Figures 4.1 and 4.2 are taken from the report and provide a summary of selected physical and chemical characteristics of Auke Bay for the period 1961-1968. Figures 4.1 and 4.2 are taken from the report and greatest temperature and salinity range (<2°C to 17°C and 2°/00 (parts per thousand) to 3°00, respectively). This variation decreased with depth, and at 50M the tem- perature range was from 2°C to 7.8°C and the salinity range 30°/oo to 31°/o0. For temperature there appears to be very little change below 30M. Figures 4.3 and 4.4 are also from the report by Bruce et al. (1977) and show representative vertical profiles for temperature and salinity for the months January, April, July and October. There appears to be even less data available on the seasonal abundance of fouling organisms larvae for the waters of interest. Only one publication could be located, and it is also for the Auke Bay region. The study by Wing and Reid (1972) was conducted from late fall of 1962 through January 1964. Their data indicates that the major hard foulers (barnacles and mussels) have larvae present in abundance in April, May, and June. In 1963 the mussel lar- vae were most abundant in May and June, and the barnacle nauplii (larvae) in April, May, and June. The average total numbers of zooplankton in the water column ranged from approximately 1/3 in January to 438/M> in June. In 4.9 TEMPERATURE (°C) 3S yp. : 12 | T 10M aoe 82 Ab ae 9F Ft | | fos eh ta | ] ‘Te Aipee-0[ b . MONTH FIGURE 4.1. Observed Water Temperatures (°C) at Selected Depths in Auke Bay, Alaska, 1960-1968 Source: Bruce 1977, p. 5. 4.10 SALINITY (°/00) MONTH FIGURE 4.2. Observed Salinities (9/00) at Selected Depths in Auke Bay, Alaska, 1960-1968 Source: Bruce 1977, p. 5. 4.11 & JANUARY @ APRIL © JULY © OCTOBER DEPTH (M) 10 TEMPERATURE (°C) FIGURE 4.3. Typical Profiles of Temperature (°C) in Auke Bay, Alaska, for January, April, July, and October 1960-1968 Source: Bruce 1977, p. 5. 4.12 4 JANUARY @ APRIL oO JULY O OCTOBER DEPTH (M) 0 16 QW 118 #19 #2 2 2 2 2 2 26 27 28 209 «230 31 32 SALINITY (9/00) FIGURE 4.4. Typical Profiles of Salinity (9/00) in Auke Bay, Alaska, for January, April, July, and October 1960-1968 Source: Bruce 1977, p. 5. the period from April through June, barnacle nauplii make up almost one half of the total numbers of zooplankton collected (Wing and Reid 1972). Unfortu- nately, data for other years or geographic locations of interest were not available to determine how the time of appearance and abundance of those orga- nisms varies. 4.2 ASSESSMENT OF CORROSION PROBLEMS While marine fouling is the primary problem associated with the use of sea water as a heat source, the problem of corrosion must be addressed whenever 4.13 sea water is used. In general, for this application, corrosion problems can be alleviated through the proper selection of piping and heat exchange mate- rials. PVC piping and fittings can be used throughout the sea water handling system. The only places where metal components are required are in the pump and the heat exchanger. According to Laque (1975, p. 257) the choice of materials for piping for sea water systems should be based on the following criteria: 1. Ability to resist general and localized corrosion such as pit- ting and impingement attack throughout all the flow velocities that may be encountered. This range extends from prolonged stagnation in dead end lines to the high degree of localized turbulence created downstream of elbows, downstream of partially throttled valves, or adjacent to pump discharges. 2. Galvanic compatibility with metals used for associated compo- nents such as valve bodies and pump casings. 3. Freedom from fouling by macro marine organisms such as barna- cles, mussels, and hydroids. 4. Amenability to fabrication by conventional practices including pipe bending, welding, and brazing. He goes on to say: The alloy that satisfies all of these criteria to the greatest extent is the 90% copper 10% nickel alloy containing about 1.25% iron as covered by ASTM designation B-466-68 for seamless pipe and ASTM des- ignation B-467-68 for welded pipe (Laque 1975, p. 257). Fortunately, copper-nickel is the most commonly used metal for use in heat exchangers in WSHPs. Either a 90% copper 10% nickel with 1.25% iron or a 70% copper 30% nickel alloy with 1.0% iron should be specified for any sea water heat pump application. Typical corrosion rates for copper-nickel alloys in sea water are on the order-of-magnitude of 0.1 to 0.5 mils per year (Laque 1975, p. 146). To reduce corrosion to a minimum the limiting design velocities shown in Table 4.1 should be used. 4.14 TABLE 4.1. Suggested Limiting Design Velocities for Copper Alloys in Sea Water Piping Systems Limiting Design Velocity (ft/sec) Pipe Sizes Alloy Under 3 in. 4-10 in. Over 10 in. 90-10 Copper Nickel 8 10 12 70-30 Copper Nickel 10 12 15 Source: Laque 1975, p. 258. Corrosion could be a problem for submersible pumps of metallic construc- tion operating in sea water. At the NMFS Auke Bay Laboratory submersible pumps are used to circulate sea water through the sea water piping system. Experi- ence with submersible pumps in this application has not been entirely suc- cessful. Pumps typically last approximately two years before they must be replaced. In the majority of the cases pump failure is caused by electrical problems. The pumps used at the Auke Bay Laboratory are designed for sea water application. They have cast iron bodies with stainless steel impellers and shafts. (2) One pump manufacturer indicated that one could expect 5 to 10 year lifetimes from submersible pumps operating in sea water. (>) There could be several reasons for this discrepancy: 1) the corrosiveness of the water at Auke Bay, 2) the nature of the specific application at Auke Bay, or 3) differences in the design of the specific pumps. Little effort was made to resolve these differences as part of this project. However, any appli- cation using submersible pumps in sea water should be carefully evaluated. It appears that one good solution to the problem of corrosion in sea water pumps is to use centrifugal or jet pumps which are not submersed in the water. In many cases these types of pumps are available with non-metallic components that eliminate the problem of corrosion in the pump itself. The problems with salt water spray getting into the electric motor remain, but they are reduced. (a) Discussions with John Kinney, Alaska Regional Engineer, NMFS, May 30-June 2, 1980. (b) Discussions with Steve Phiefer, Peabody Floway Pumps, Fresno, Calif., May 29, 1980. 4.15 REFERENCES - CHAPTER 4.0 Bruce, H. E., D. R. McLain, and B. L. Wing. 1977. Annual Physical and Chem- ical poganedcapnic Cycles of Auke Bay, Southeastern Alaska. Technical eport ; - » National Marine Fisheries Service, Washington, DC. Laque, F. L. 1975. Marine Corrosion: Causes and Prevention. John Wiley & Sons, New York, NY. U.S. Environmental Protection Agency. 1976. Quality Criteria for Water. U.S. Environmental Protection Agency, Washington, DC. White, G. C. 1972. Handbook of Chlorination. Van Nostrand Reinhold, New York, NY. Wing, B. L. and G. M. Reid. 1972. Surface Zooplankton from Auke Bay and Vicinity, Southeastern Alaska, August 1962 to anuary - U.S. Dep. ommer., Natl. Oceanic Atmos. Admin., Natl. Mar. Fish. Serv., Data Rep. 72, 765 pp. 4.16 5.0 CONCEPTUAL DESIGN OF WATER SOURCE HEAT PUMP HEATING SYSTEMS - ETE EAT PUMP HEATING SYSTEMS 5.1 INTRODUCTION To make a more realistic economic evaluation of WSHPs relative to other types of heating, 4 case studies were performed. Each case involves a build- ing type and a preliminary design for a WSHP heating system. The buildings and heating systems were selected to be representative of the current Juneau residential and commercial building stock for which WSHPs appear to provide a viable alternative heating method. The buildings selected were: 1. Typical new Mendenhall Valley residence. 2. The filter building located at the Auke Bay Laboratory of the National Marine Fisheries Service (NMFS) 3. The warehouse located at the subport facilities of the NMFS 4. The salmon hatchery located near the Snettisham hydroelectric project. The building used as an example in Case 1 does not presently exist. The size, floor plan, and type of construction were chosen to be representative of typi- cal new construction in the Mendenhall Valley area. Cases 2 and 3 involve buildings which presently exist. Construction was started on the Snettisham fish hatchery (Case 4) during May 1980. In Case 1 ground water is assumed to be used as the heat source, in Cases 2 and 3 sea water is assumed to be the heat source, while in Case 4 lake water from the tailrace of the Snettisham hydroelectric project is used as the heat source. In the first three cases heating load estimates were made. In the case of the fish hatchery the design heat loads prepared as part of the design package were used directly. Using the calculated heat loads as a basis, WSHP based heating systems were designed for each case. 5.1 In Section 5.2 each of the case studies is presented. In Section 5.3 the heat load methodology and results of the heat load calculations are presented. In Section 5.4 the heating systems using WSHPs are presented for each of the 4 cases. 5.2 BUILDING DESIGNS AND HEAT PUMP SYSTEMS 5.2.1 New Residential Construction in the Mendenhall Valley This case evaluates a typical new residence in the Mendenhall Valley area. The structure is a two-story, split entry home with an attached garage. There are 1290 sq. ft of living space on the upper level and 530 sq. ft on the lower level. The floor plan is shown in Figure 5.1. The number and letter designa- tions in Figures 5.1 through 5.6 refer to information about the doors and win- dows, respectively, necessary for the heat load calculations in Appendix B. The exterior walls are assumed to have 2x6 studs insulated with 5 1/2 in. fiberglass batts to a value of R-19. The ceiling is assumed to be insulated to a value of R-38 (approximately 12 in. of fiberglass). All windows are to be double glazed aluminum frame with a thermal barrier. The perimeter of the foundation is insulated with 1 1/2 in. of rigid insulation. As mentioned above, a WSHP using ground water is used as a heat source for comparative purposes. The high ground water table (about 20 ft below the surface) in the Mendenhall Valley is an attractive source of heat for WSHPs since pumping head losses (and, therefore, pumping costs) are low. In addi- tion, there appears to be an ample supply of water for at least a moderate number of WSHP applications. The temperature of ground water in the Mendenhall Valley area is generally between 40 and 46°F (McConaghy 1969, p. 57-59). Water temperatures in this range are relatively low for use with WSHPs but are acceptable. (@) The chemical composition of the water also appears to be acceptable (McConaghy 1969, p. 57-59). () (a) Discussions with WSHP manufacturers and WSHP manufacturer's descriptive literature, March-April 1980. (b) At this point it is important to note that the temperature and chemical composition of the water to be used in a WSHP should be carefully evalu- ated on a case-by-case basis before a WSHP heating system is installed. 5.2 | ak | MASTER SUITE Fy Kitchen Ff bINiNG 3-4ei1'-8 A ioxi'-8 ——10%x11'-8 VAULTED CEILING FAMILY ROOM 17'-4x14'-8 GARAGE 20'x26'-4 STUDIO/GUEST 14'x11'-6 “ LOWER LEVEL FIGURE 5.1. Floor Plan for Typical New Residential Construction in the Mendenhall Valley 5.3 5.2.2 Filter Building at the Auke Bay Laboratory This case evaluates the use of a residential sized heat pump to heat an existing building at the NMFS Auke Bay Laboratory. The "filter building" is a one-story frame structure which is used to house sand filters and the fresh water storage tanks, and for storage. While it is relatively small (704 sq. ft), it has a relatively high design heat load typical of new resi- dential buildings. The floor plan for this building is shown in Figure 5.2. STORAGE ROOM STORAGE ROOM —— 13'-2x9'7 7'-6x9'7 FILTER ROOM 21'-2x21'2 FIGURE 5.2. Floor Plan for Filter Building at Auke Bay Laboratory 5.4 The exterior walls have 2x4 studs. All walls except the west wall of the filter room are insulated with 3 1/2 in. fiberglass batts. The ceiling is also insulated with 3 1/2 in. fiberglass batts. The windows are single glazed and are non-opening. The building is set on blocks approximately 8 in. above the ground level. There is no floor insulation. In this case sea water is used as a heat source. The Auke Bay Laboratory has an existing sea water handling system with a capacity of about 125 gallons per minute (gpm). A portion of this water would be taken from the seawater piping system, used as a source of heat, and then returned to the effluent sysem. The water will be obtained in the main laboratory building which is located about 15 ft south of the filter building. The water is assumed to be piped around the east and north sides of the building to the heat pump which will be located in the larger room. With the present system the seawater is filtered using sand filters to remove fouling organisms. The presence of the existing seawater handling system makes this applica- tion an attractive demonstration for a system using seawater as a heat source. While the water may pick up a small amount of heat as it flows through the fish tanks, or wet lab area, it should not have any significant effect on the performance of the heat pump for demonstration purposes. The use of seawater as a source of heat for WSHPs was discussed earlier in Chapter 4. In fact, much of the data about seawater presented in Chapter 4 was obtained from the Auke Bay area. 5.2.3 Warehouse on Juneau Waterfront This case involves a WSHP heating system using seawater as a heat source to provide heating for a warehouse/shop building at the subport facilities of the NMFS. This is a Butler building with outside dimensions of about 60 ft by 120 ft. The floor plan for this building is shown in Figures 5.3 and 5.4. As shown the building serves as a combination warehouse, garage, and shop build- ing. The building is immediately adjacent to the dock and is about 60 ft from sea water in the Gastineau Channel. All exterior walls and the ceiling are formed by sandwich panels com- posed of painted galvanized steel on the exterior and interior with a core of approximately 1 in. of polyurethane foam. The estimated R value of this wall 5.5 9°S — Tr oo -® WOOD SHOP —- J MACHINE SHOP ®- 32' x 59" 40' x 26' (A) ENTRY -(A) one Ge TOILET ROOM )- 9x13" —(@) OFFICE @- 10'x20' BOILER ® 121" ROOM ®-] ion ® PASSAGE 19'x 12! @- STAIRS @)- GARAGE 59" x 60! a FIRST FLOOR —-— 2 FIGURE 5.3. Floor Plan for First Floor of Warehouse on Juneau Waterfront REAR STORAGE AREA 27'x 20! FRONT STORAGE AREA 39' x 33" HALL 8'x19' DIVER SUPPLY ROOM 17'x 19" OPEN 19' x60! mt STAIRS GARAGE 59' x 60! FIGURE 5.4. Floor Plan for Mezzanine of Warehouse on Juneau Waterfront structure is 10, (4) The walls of the rooms on the lower level are furred out about 12 in. but do not include any additional insulation. The building has a poured concrete floor with no edge insulation. In this case sea water is used as a heat source. An intake structure containing a submersible pump would be located below the pier. Water supply lines would run from the intake below this pier dock, along the north side of the building, and to a hydrotank located under the stairs in the garage area of the building. Intermittent chlorinatione would be used to kill any fouling marine organisms. Three single package unitary WSHPs are used in the design. The disposal piping would return the water along a similar route to the channel. 5.2.4 Salmon Hatchery Near Snettisham Hydroelectric Project This case considers the use of WSHPs to heat the Snettisham salmon hatch- ery which is to be built for the Alaska Department of Fish and Game during the summer and fall of 1980. This structure will have a single story and include office, shop, laboratory, incubation, and egg handling and storage rooms. The floor plan is shown in Figures 5.5 and 5.6. While the building has over 9000 sq. ft its heat load is relatively low because the majority of the build- ing is only to be heated to 45°. The exterior walls will have 3x6 framing with 5 1/2 in. fiberglass batt insulation. The ceiling will have about 12 in. of fiberglass insulation. In most cases in Alaska the surface water is too cold for use as a heat source for a WSHP. In this case, however, the water comes from the tailrace of the Snettisham hydroelectric facility. This water is taken from Long Lake and is heated slightly as it goes through the tunnel and generator turbine. The water temperature is about 41°F throughout the year. In this case three single package unitary WSHPs are used to heat the building. The water will be taken from the incubation room water supply head- boxes. Cooled water would be discharged to the building drain system. (a) Discussions with Mike McGuire, Engineered Structures Inc., Richland, Wash- ington, April 17, 1980. 5.7 ® ® GENERATOR ROOM 25'x 16' 20' x 10'_ EGG SORTING FORMALIN AND HANDLING STORAGE 20'x 38! -8 _@) INCUBATION ROOM . ® 165'x 38" -8 “Ne MECH. @)— #2 13' x 10! WEST END @) @) 228' FIGURE 5.5. Floor Plan for West End of Snettisham Salmon Hatchery #1 SHOP 17x10 17' x 20' INCUBATION ROOM 165' x 38! -8 OFFICE 17'x 10' Q (A) @) EAST END 228! FIGURE 5.6. Floor Plan for East End of Snettisham Salmon Hatchery 5.8 5.3 HEAT LOAD METHODOLOGY AND ANALYSES Once the structural and heat transfer characteristics of the buildings to be evaluated have been determined the next step is to calculate the heat load for the building at the heating design conditions for the area in which the building is located. The heating design conditions refer to the conditions that give the maximum heat load that would be expected to normally occur in an area. For the Juneau airport the outdoor design temperature is -5°F (ACCA 1975, p. 27). The design temperatures commonly used for other locations in the Juneau area vary. The outdoor design temperatures used in the 4 cases evaluated in this report are presented in the second column of Table 5.1. The other temperature necessary to compute the design heat load is the indoor temperature that is to be maintained. For a residence this temperature is commonly 70°F. The indoor design temperatures used in this analysis are presented in the third column of Table 5.1. In some cases different parts of a building may have different indoor design temperatures (the Snettisham salmon hatchery, for example). The difference between the outdoor and the indoor design temperatures is the design temperature difference which is used to com- pute the heat loads (Column 4 in Table 5.1). TABLE 5.1. Summary of Assumptions and Results of Heat Load Calculations Outdoor Interior Design Design Design Temp. dake Temp. Temp. Difference Conditions Case (°F) (°F) (°F) (Btu/hr) 1. New Residential -15 70 85 49,000 Construction Mendenhall Valley 2. Filter Building -5 60 65 57,000 Auke Bay 3. Warehouse -5 60 65 214,000 Subport-Juneau 4. Fish Hatchery -20 45 65 159,000 Snettisham 70 90 69,000 , Total 228 ,000 5.9 Generally, calculation of the design heat loads for any structure involves determining the areas and insulating value of all exterior surfaces (exterior walls, windows, and doors) exposed to the outside air. Knowing the tempera- ture difference existing across these surfaces at design conditions then allows the heat loss per sq. ft of surface area for each of the exterior surfaces to be determined. The heat losses for each surface are then added together to yield the total heat loss for the structure. Allowances are also made for air infiltration around windows and doors as well as for normal opening and closing of the windows and doors. The procedures to determine heat loads for struc- tures are quite common and easy to use. The methodology used to compute the heat loads in this report is presented in a report published by the Air Con- ditioning Contractors of America (ACCA 1975). The design heat loads for the structure evaluated in this report are pre- sented in the 5th Column of Table 5.1. The detailed heat load calculation work sheets for the first three cases are presented in Appendix B. The design heating loads for the Snettisham fish hatchery were obtained from the mechan- ical contractors. These are also presented in Appendix B. 5.4 HEAT PUMP SYSTEM DESIGNS Heating systems using WSHPs for space heating were designed for each of the example buildings. Water sources appropriate to each structure were used: fresh water from a shallow aquifer for the Mendenhall Valley residence, sea water from the Auke Bay Laboratory sea water supply for the filter building, sea water taken from Gastneau Channel for the subport warehouse, and fresh water from the Snettisham hydroelectric facility tailrace for the fish hatch- ery. In each case the temperature of the water source would be approximatly 40°F, near the lower limit for WSHPs, and somewhat limiting the availability of suitable units. A forced air heat distribution system was used in all cases because water-to-water heat pump units capable of delivering condenser water at tem- peratures adequate for satisfactory operation of convection heating terminals when operating on 40°F source water are not presently commercially available. Currently available water-to-water units are capable of delivering water at temperatures satisfactory for radient heating applications; radient heating 5.10 designs however, were not within the scope of this study. Development is underway on "cascaded" heat pumps using staged refrigeration cycles. Such machines might be capable of providing condenser water of sufficiently high temperature to permit use of convection heating terminals. The designs arrived at in this study are not necessarily optimum. They represent first iterations on the respective design problems and could likely be improved from both technical and economic standpoint by further analysis. Design considerations warranting additional analysis include air distribution system and water supply system pressure drops. Figures showing the piping and ductwork designs for each of the 4 cases are presented in Appendix C. 5.4.1 Mendenhall Valley Residence Heating System Design The heating system for the Mendenhall Valley residence uses a nominal 60,000 Btuh heating capacity WSHP supplied by fresh water obtained from the shallow aquifer underlying the Mendenhall Valley. Heat distribution is by a forced warm air system using extended plenum distribution. Wall thermostat control is provided. The heat pump, located in the mechanical room (Figure 5.1 and C.2, Appen- dix C), is an upright single-package heat-only unit rated at 50,000 Btuh with 40°F inlet water temperature. This is adequate for the design heat load of 47,000 Btuh (Table 5.1). This unit is equipped with integral condenser and blower, air filter and water flow control values. No backup resistance heat- ing is provided in accordance with standard WSHP design practice. Fifteen gpm of 40°F water is required at design operating conditions. Water is provided by a well system serving both domestic and heating needs. This system consists of a 30 foot deep, four inch diameter drilled well equipped with a submersible pump capable of supplying 30 gpm at 60 psi. Pres- sure control is by hydrotank and pump control pressure switch (Figure C.1). Use of the submersible pump (though more costly than the shallow well pumps in common use in the Mendenhall Valley) is desirable because of the relatively high water flow rate required and reduced pumping power requirements. Water flow control is by integral water flow regulating valves: Discharged water is 5.11 returned to the aquifer by an injection well. The heat pump water supply is provided with isolation and boiler drain valves for heat exchanger backflush- ing, a supply line strainer, and temperature and pressure instrumentation. Piping from the well to the house and from the house to the injection well is PVC. Interior piping is copper. All piping is insulated. An extended plenum system is used to distribute heated air to occupied spaces (Figure C.2). Overhead supply registers are used in the lower level and floor registers in the upper level; typical of conventional warm air heating systems. Returns are provided on each floor. Ductwork is of galvanized steel using standard rectangular and round sections. Because of low differential air temperatures across the condenser, heat pumps commonly require a large airflow rate necessitating ductwork of relatively large cross-sectional area. This distribution system is based on 2150 CFM air flow at 0.3 inch water gage static head. A wall thermostat provides blower and compressor control. Cost Estimate The cost estimate for this design, based on new construction, is summa- rized in Table 5.2. Included are regional cost adjustments, contractor's over- head and profit and a contingency allowance of 7.5%. 5.4.2 Auke Bay Filter Building Heating System Design The heating system for the Auke Bay filter building uses a WSHP supplied by sea water obtained from Auke Bay via the laboratory sea water system. Heat distribution is by a forced air system using extended plenum distribution. Wall thermostat control is provided. The heat pump, located in the northwest storage room (Figure 5.2), is an upright single-package heat-only unit rated at 60,000 Btuh with 40°F inlet water temperature. This is adequate for the design heat load of 57,000 Btuh (Table 5.1). This unit is equipped with integral condenser and blower, air filter and water flow control valves. No backup resistance heating is provided. 5.12 TABLE 5.2. Cost Estimate, Mendenhall Valley Residence (1980$) Material and Item Labor Equipment Subcontracts Total Ductwork and Accessories 3360 1100 Water Supply and Recharge 550 1310 1710 Heat Pump 390 4360 Electrical and Control 30 40 Test and Balance _180 Ss <—— Subtotal 4510 6810 1710 Contractors op (4) 1920 _680 _c- Subtotal, inc O&P 6430 7990 1710 15,630 Contingency, 7.5% _ 1170 Total 16,800 Credit for conventional water system 1300 Net Total Cost 15,500 (a) Contractor's overhead and profit: 10% on material and equipment, 42.6% on labor. Seventeen gpm of 40°F water is required at design operating conditions. Water is taken from a sea water header in the "wet lab". An air break is provided between the laboratory sea water supply and the heat pump water system by use of a sump with float valve level control as suction for the water supply pump (Figure C.3). A self-priming multistage jet pump takes suc- tion on the sump to supply 20 gpm at 50 psi pump discharge pressure. Pressure control is by air-loaded hydrotank and pump control pressure switch, located in the wet lab adjacent to the pump. A 1-1/4 PVC water supply line runs from the hydrotank to the north wall of the laboratory via the laboratory utilador, and thence underground to the filter building for a total sump-to-heat pump distance of approximatly 150 feet. Water is returned by the same route to the main sea water drain in the laboratory utilador. The water supply is provided 5.13 with isolation and boiler drain valves at the heat pump for heat exchanger backflushing, a supply line strainer, and temperature and pressure instrumen- tation. Use of the filtered laboratory sea water supply should eliminate the need for anti-fouling chlorination. Supply and return piping and fittings are PVC; copper is used at the heat pump. The jet pump is a standard commercial model with body and impeller of plastic material. The air-load hydrotank is also a standard commerical model with a plastic water bag. A extended plenum system is used to distribute heated air to the filter room and the two storage rooms (Figure C.4). Rectangular galvanized steel con- struction with vertical-face supply registers are used. A single return is provided low or the north wall of the filter room; transfer grills facilitate cold air return from the supply rooms. The distribution system is based on a 2325 CFM air flow at 0.3 inch water gage external static pressure. A wall thermostat provides blower and compressor control. Cost Estimate The cost estimate for this design, based on retrofit construction is sum- marized in Table 5.3. Included are regional cost adjustments, contractor's overhead and profit and contingency allowance of 10%. 5.4.3 Warehouse on the Juneau Waterfront Heating System Design The heating system for the subport warehouse uses three WSHPs supplied by sea water taken at depth from Gastineau Channel via a pierside submersible pump. Two independent heating zones are established, each supplied by a reduc- ing trunk forced air distribution system. Zone I includes the office, boiler room, woodshop and machine shop. One heat pump of 72,000 Btuh nominal heating capacity with wall thermostat control is provided. Zone II includes the garage and the entire mezzanine level. Two heat pumps of 72,000 Btuh nominal heating capacity, installed in tandem, are used. Staged control using room and outdoor thermostats is provided. The subport warehouse heating system is designed as a demonstration retrofit to be installed in conjunction with the existing heat- ing system. As such the location of equipment may not be optimal. The Zone I heat pump, an upright single package unit, is located against the north wall of the woodshop (Figure C.5). This is a heat-only unit rated 5.14 TABLE 5.3. Cost Estimate, Auke Bay Filter Building (1980$) Material and Item Labor Equipment Subcontracts Total Ductwork and Accessories 1890 630 90 Water Supply and Return 2670 1480 680 Heat Pump 470 4930 -- Electrical and Control 120 180 -- Test and Balance 210 -- -- Subtotal 5360 7220 770 Contractors op (4) 2280 720 - Subtotal, inc O&P 6430 7990 1710 16, 350 Contingency, 10% __ 1640 Total 17,990 (a) Contractor's overhead and profit: 10% on material and equipment, 42.6% on labor. at 72,000 Btuh with 40°F inlet water temperature. Integral condenser and blower, air filter and water flow control valves are provided. No backup resistance heating is provided. Eighteen gpm of 40°F water is required at the design heating load. Air distribution for Zone I is provided by a reduc- ing trunk air distribution system with a main supply trunk extending east-west along the ceiling of the woodshop with branches to the office, machine shop and boiler room. Vertical face supply registers are used. Two return grills are provided on a short return trunk with one grill located in the woodshop and the second in the machine shop. A transfer duct to the machine shop is used for boiler room return, and a transfer grill provides return from the office. The distribution system is based on 2500 CFM air flow at 0.15 inch water gage external static pressure. (4) All ductwork is exposed and uninsu- lated and is of rectangular galvanized steel construction. Fire dampers are (a) Blowers having greater capacity are available which might permit use of more compact ductwork. 5.15 provided at the boiler room penetrations. Zone I blower and compressor contro] is provided by a wall-mounted thermostat. Two horizontal single package heat pumps, mounted in the overhead of the mezzanine, are used as heat sources for Zone II (Figure C.6). These are heat- only units rated at 72,000 Btuh each with 40°F inlet water temperature. Con- denser and blower, air filters and water flow control valves are integral to the units. No backup resistance heating is provided. Eighteen gpm of 40°F water is required by each unit at design conditions for a total of 36 gpm for Zone II. The two Zone II units are installed in tandem, providing 5000 CFM airflow at 0.15 inch water gage external static pressure. Staged control is provided such that the second unit is operated only at heat loads exceeding the capacity of the first unit. Electrical lockout of the second unit is provided by an outdoor thermostat set at the balance point temperature. Room tempera- ture control is provided by a wall-mounted thermostat. Zone II air distribution is provided by a reducing trunk air distribution system having a main supply trunk extending east-west along the ceiling of the garage and mezzanine. Branches extend to the rear storage area and diver supply room. Vertical-face supply registers are used throughout. Return grills are located on either side of the garage near floor level with supple- mentary returns in the front storage area, rear storage area and diver supply room. All ductwork is exposed and uninsulated and is of rectangular galva- nized steel construction. Backflow prevention dampers are provided at each heat pump discharge. Sea water is provided to the Zone I and Zone II heatpumps by a common sea water system supplied by a pierside submersible pump. Intermittent chlorina- tion is used to retard fouling by marine organisms. Automatic pressure control is provided by an air-loaded hydrotank (See Figure C.7). A 5.7 horsepower submersible pump capable of delivering 60 gpm at 200 foot head is suspended in an eight inch steel casing mounted inboard of the pier face. The casing is provided with several intake slots located at depths of 20-25 feet below low water level. Pump discharge is directed through a basket strainer then through an insulated 2 inch supply line running below the pier deck to the seawall and thence underground along the north side of the ware- house to the hydrotank located under the stairs. The chlorinator discharge is 5.16 routed back along the supply line to the vicinity of the casing head where it taps the main supply. Intermittent chlorination is provided by automatic con- trol. The sea water supply header is routed back along the north wall of the warehouse at ceiling level with branches to the Zone I and Zone II units. Each heat pump is provided with an inlet throttle valve for system balancing and a gate valve is provided on the discharge to allow unit isolation for maintenance. Boiler drains on the inlet and discharge piping of each unit allow heat exchanger backflushing. Supply and discharge temperature and pres- sure instrumentation are also provided. Sea water returns to the channel by a 2 inch header discharging at the seawall. Sea water piping and fittings are of PVC for corrosion resistance. The submersible pump is of iron construction with a stainless steel shaft and is rated for salt water use. Fittings not available in PVC are of bronze. All piping is insulated. Cost Estimate The cost estimate for this design, based on retrofit construction, is sum- marized in Table 5.4. Included are regional cost adjustments, contractor's overhead and profit, and a contingency allowance of 10%. 5.4.4 Snettisham Salmon Hatchery Heating System Design The conceptual heating system for the Snettisham Salmon Hatchery uses three water source heat pumps supplied with fresh water from the Snettisham hydroelectric facility tailrace. Two independent warm air distribution sys- tems are established. Zone II includes that portion of the hatchery building having a 45°F interior design temperature, and utilizes two water source heat pumps of 85,000 Btuh nominal heating capacity, installed in tandam and controlled for staged compressor operation. The other zone includes that por- tion of the building having a 70°F interior design temperature, and utilizes a single heat pump having 72,000 Btuh nominal heating capacity. The salmon hatchery heating system is designed as a new construction system and insofar as appropriate to a system utilizing water source heat pumps, duplicates the control, ventilation and safety features of the hatchery heating and ventila- tion system as presently designed. 5.17 TABLE 5.4. Cost Estimate, Subport Warehouse (1980$) Material and Item Labor Equipment Subcontracts Total Ductwork and Accessories 11,370 3330 80 Water Supply and Return 8220 8250 1390 Heat Pump 1470 19,810 -- Electrical and Control 2530 1470 -- Test and Balance -- -- 1380 Subtotal 23,590 32, 860 2850 Contractors og!) 10,050 3290 < Subtotal, inc O&P 33,640 36,150 2850 72,640 Contingency, 10% 7260 Total 79,900 (a) Contractor's overhead and profit: 10% on material and equipment, 42.6% on labor. Zone I includes the portion of the structure having a 70°F interior design temperature. This area includes the office, shop, mechanical room #1, laboratory and restrooms. An upright single package heat pump rated at 72,000 Btuh heating capacity with 40°F inlet water temperature is used as the heat source for Zone I. This unit is located against the south wall of mechanical room #1 (Figure c.9). (4) This unit includes an integral blower and condenser, air filter and water flow control valves. Air distribution for Zone I is provided by a reducing trunk air distribu- tion system located in the overhead of the hallway (Figure C.9). A ceiling diffuser is provided in the hallway and branches extend to the shop, office, men's and women's restrooms, and the laboratory. Each branch terminates with (a) To accomodate the Zone I heat pump it would be necessary to relocate the domestic water system hydrotank to the north wall of mechanical room #1, adjacent to the domestic water pump. No other major relocations would be required. 5.18 a high-sidewall supply register except for the laboratory, which is equipped with a ceiling diffuser. Two returns are provided, one from the shop and a second from the hall. Fresh air is introduced into the system by ductwork leading from the exterior fresh air intake on the north wall of mechanical room #1. Thermo- static control of outside and return air mixing dampers is provided. Exhaust from Zone I is by a wall exhaust fan located in the shop and ceiling exhausts in the restrooms, as provided in the current hatchery plan. Fire dampers are installed at all penetrations to mechanical room #1. The distribution system is based on 2500 CFM air flow at 0.5 inch water gage external static pres- sure. All ductwork is of rectangular galvanized steel constructon. Return and outside air ducts are provided with sound attenuating lining. Safety and ventilation controls similar to those of the existing hatchery heating and ventilation system are provided. Room temperature control is by wall-mounted thermostat. Zone II includes the portion of the building having a 45°F interior design temperature. This area includes the egg handling room, incubation room, storage room and mechanical room #2. Two upright single package heat pumps installed in mechanical room #1 are used as the heat sources for this zone. These units are rated at 85,000 Btuh heating capacity with 40°F inlet water temperature. These units are located side by side out from the west wall of mechanical room #1 (Figure C.9). Each unit includes an integral blower and condenser and water flow control valves. Separate filters located in the com- mon return duct are used. Heated air for Zone II is taken through backflow prevention dampers at the discharge of each unit then distributed through a reducing trunk system. Two main branches are provided (Figure C.9); one along the north wall of the incubation room and the second along the south wall of the incubation room and continuing through mechanical room #2 to serve the egg handling room. Vertical-face supply registers are provided along both exterior walls of the incubation room, on the exterior wall of the mechanical room #1, and along the east wall of the egg handling room. The return is located at the northeast corner of the incubation room. This arrangement is similar to the existing ventilation system. Return air passes to a mixing chamber, located in mechanical room #1, where outside air is admitted from the fresh 5.19 air intake on the north wall of mechanical room #1. Thermostatic control of outside and return air mixing dampers is provided. Exhaust from Zone II is provided by the existing exhaust fan EF-1. This fan exhausts from the storage room which is provided with transfer ducting from the incubation room. Fire dampers are located at ductwork penetrations to the storage room. The distri- bution system is based on 6000 CFM air flow at 0.5 inch water gage external static pressure. All ductwork is of rectangular galvanized steel construction and return and outside air ducts are provided with sound attenuation lining. Safety and ventilation controls similar to those of the existing heating and ventilation system are used. Staged control is provided such that the second unit is normally operated only at heat loads exceeding the capacity of the first unit. Electrical lockout of the second unit is provided by an outdoor thermostat set at the balance point temperature. Room temperature control by wall-mounted thermostat. Water requirements at design heating capacity are 18 gpm for the Zone I unit and 21.6 gpm for each of the Zone II units, at 40°F inlet water tem- peratures. Water is supplied from the domestic water supply system, modified to provide increased delivery capacity. Water tapped upstream of the chlori- nator (Figure C.8) is delivered to the heat pumps by a 2 inch header. The supply header is equipped with backflow prevention and isolation valves, a Y-type strainer, and pressure and temperature instruments. One inch supply and return branches serve each unit. Each supply branch is provided with a globe valve for system balancing. Gate valves are provided on the return branches for unit isolation. Boiler drain valves are installed on the supply and return branches for heat exchanger backflushing. Supply and return pres- sure instrumentation and discharge temperature instrumentation are also sup- plied. A 2 inch combined return header discharges to the building drain system. All piping is of copper with fittings of bronze, and is insulated throughout. The domestic water supply system would retain its current con- figuration but would be increased in capacity from 20 to 80 gpm at 60 psig. (@) (a) System capacity requirements could be reduced by use of a reverse acting pressure switch on the domestic water system hydrotank. This switch, which would interrupt compressor operation during momentary domestic demand peaks, would reduce system capacity requirements to 60 gpm and would reduce pump cycling. 5.20 A three horsepower supply pump would be required and pipe sizes would be increased to 4 inches for the headbox downcomer, 2 1/2 inches for the pump suction and 2 inches for the pump discharge to the hydrotank. Cost Estimates The cost estimate for the Snettisham Salmon Hatchery heating and ventila- tion system, based on new construction, is summarized in Table 5.5. Included are regional cost adjustments, contractor's overhead and profit and a contin- gency allowance of 7.5%. TABLE 5.5. Cost Estimate, Snettisham Salmon Hatchery (1980$) Material and Item Labor Equipment Subcontracts Total Ductwork and Accessories 12,570 5910 -- Water Supply and Return 1710 1570 -- Heat Pump 1680 21,430 -- Electrical and Control 540 130 7240 Test and Balance -- -- 1610 Subtotal 16,500 29,040 8850 Contractors oap(4) 7030 __2900 Subtotal, inc O&P 23,530 31,940 8850 64, 320 Contingency, 7.5% 4830 Total 69,150 (a) Contractor's overhead and profit: 10% on material and equipment, 42.6% on labor. 5.21 REFERENCES - CHAPTER 5.0 Air Conditioning Contractors of America. 1975. Load Calculation for Residen- tial Winter and Summer Air Conditioning. Washington, D.C. McConaghy, J. A. 1969. Hydrologic Data of the Juneau Borough, Alaska. Pre- pared by the United States Sastosieat Survey in cooperation with The Greater Juneau Borough. 5.22 6.0 EVALUATION OF ALTERNATIVE DESIGNS 6.1 INTRODUCTION In this chapter the WSHP-based heating system designs presented in Chap- ter 5 are compared with alternative methods of heating typical for that type of structure. For the new residence case, WSHP heating is compared to elec- trical resistance baseboard (both direct and fluid filled), oil-hydronic, and air to air heat pump heating. For the filter building and the warehouse WSHP heating is compared with the existing heating system; forced air oil furnace heating in the case of the filter building and oil-hydronic heating in the case of the warehouse. In the Snettisham salmon hatchery case the WSHP design is compared with the electrical resistance heating system presently designed for the building. The alternative heating systems are compared based upon three considera- tions: 1) life cycle costs, 2) technical viability, and 3) effect on fossil and electrical energy use. The life cycle cost comparison looks at the total cost of heating the structures with the alternative methods discussed above over the 10-year period from 1981 through 1990. The purpose of the technical evaluation is to compare the system from the standpoint of ease of installa- tion, operation, and maintenance. Because of the high economic and strategic cost of fuel oi] in the Juneau area (as well as in the U.S., as a whole) and the availability of electric power in the Juneau area, the impact of the WSHP heating systems on the consumption of these energy sources is also evaluated. 6.2 LIFE CYCLE COST COMPARISONS As pointed out above, this life cycle cost evaluation looks at the total cost of heating the structures over the 10-year period from 1981 to 1990. Three cost components are evaluated for each system: energy costs, operating and maintenance (0&M) costs, and capital investment costs. This comparison takes into account the effects of inflation on the energy costs and the O&M costs, and the costs of financing the initial purchase of the system. 6.1 A key parameter value that must be established and used throughout the life cycle cost comparisons is the rate of inflation. As discussed in Chap- ter 1, the increase in energy prices can be keyed to the rate of inflation. In addition, the discount rate at which the initial investment is financed and the rate of increase of the O&M costs can be keyed to the rate of inflation. In this evaluation the rate of inflation over the 1981-1990 time period is assumed to be 8% per year. While this is considerably lower than the current rate of inflation (approximately 15-18% per year) it is a relatively high value for the U.S. for a 10-year period. Using the rate of inflation as a basis, the various discount and escala- tion rates to be used in the cost analysis were selected. They are presented in Table 6.1 below. TABLE 6.1. Discount and Escalation Rates Assuming an 8% Rate of General Inflation R/YY Fuel Oil Price Escalation ll Electricity Price Escalation 4 O&M Cost Escalation 8 Financing Discount Rate 11 The methods used to compute the annual costs are similar for all the alternative structures and heating methods analyzed. The general methods and data used in the cost analyses are described in this section while the data and assumptions specific to each alternative structure are described in Sec- tions 6.2.1 through 6.2.4. The annual energy costs are computed using the price of energy (either fuel oil or electricity) and the annual energy consumption. The prices of fuel oil and electricity in the Juneau area assuming an 8% rate of inflation from 1981 to 1990 were presented in Figures 1.1 and 1.2, respectively. 6.2 The annual energy consumption is computed using the heating efficiency of particular heating methods and the annual heating requirements of the particu- lar structure. The heating efficiencies of the various heating methods are presented along with the descriptions of the specific cases in the following four sections. The annual heating requirement is determined using the outdoor temperature distribution for a year (which gives the hours per year that the outside temperature is within specific temperature ranges) and the heat load at that temperature. Since the heat load for a structure is assumed to be a linear function of the outside temperature, the heat load at any specific tem- perature is proportional to the heat load at design conditions. The design heat loads for the four structures are presented in Table 5.1. By multiplying the heat load (Btu/hr) of a structure at a specific temper- ature by the number of hours that the outdoor temperature is at that tempera- ture and then adding the heat loads (Btu) at the various temperatures together, the total annual heating requirement is computed. The annual heating require- ment calculations for the cases evaluated in this report are presented in Appendix D, Tables D.1 through D.5. They are summarized in Table 6.2 below. TABLE 6.2. Annual Heating Requirement for Structures Evaluated Annual Heating Requirement Case tu ~ _XkWAy 1. New Residential Construction Mendenhall Valley 183,917 53,875 2. Filter Building Auke Bay 125,508 36,773 3. Warehouse Subport - Juneau 471,216 138,065 4. Fish Hatchery Snettisham 699,779 205 ,033 6.3 The annual O&M costs are computed based upon the number of hours that a repairman would be required to maintain the heating system. No material costs are included in the 0& category for any of the heating systems. There is little information available on the maintenance materials cost for heating sys- tems. It was assumed that either no materials would be required beyond the initial installation or that their costs would be covered by warranty. The equivalent annual investment costs were computed assuming a financing discount rate of 11% and, in general, a financing period of 25 years. The com- pressor portion of both the ASHP and the WSHP heating systems were separately evaluated using a 10-year financing period to reflect their anticipated shorter lifetime. The annual energy costs, O&M costs, and capital investment costs are added together to give the total annual heating costs. To facilitate the comparison of the life cycle costs of the alternative heating methods a "levelized" cost is computed. The levelized cost is computed using the present worth of the annual costs over the time period of interest. In equation form: Levelized Cost = PWAC * CRF where PWAC CRF = capital recovery factor - the factor by which a present sum is present worth of the annual costs multiplied to find a future series that is equivalent to the present sum at a specific discount rate and time period. A capital recovery factor for 10 years at a 8% discount rate is used in this study (0.14903). In turn PWAC = }> AC, * —-—~ i=l | (1+r)! 6.4 where AC. = annual costs in year i ($) = discount rate (8%) = time period (10 years) i = year (1,2,3...n) st In the following four sections the life cycle heating costs for the alter- native heating systems are developed for the four cases considered in this report. 6.2.1 New Residential Construction in the Mendenhall Valley General details regarding the computation of the annual fuel cost was presented in Section 6.2. The heating efficiencies for the five alternative heating systems evaluated for this case are presented in Table 6.3 below. TABLE 6.3. Season System Efficiencies/COPs for Residential Heating Systems Efficiency (%) System or COP Direct and fluid- filled electrical resistance baseboard 100% 0i1-Hydronic 55% ASHP 1.92 WSHP 2.25 Electrical resistance heating is assumed to be 100% efficient. Typical resi- dential oil-hydronic heating systems have efficiencies in the 50 to 60% range. An average value of 55% is used in this case. Fuel oi] is assumed to have a heating value of 138,690 Btu/gal. An ASHP seasonal system COP of 1.92 was assumed. This value was obtained from a previous analysis of ASHP heating costs done for a residence in the Juneau area with the same outdoor temperature distribution as was assumed for the Mendenhall Valley (CH2M 1980, Appendix Table 6). 6.5 A WSHP seasonal system COP of 2.25 was assumed. Manufacturers literature gives WSHP COPs for 40°F inlet water of from about 2.75 to 4.0 (not including the power required for pumping the water). A relatively conservative value of 3.0, exluding the power required for water pumping was assumed for this eval- uation. When the power required for pumping the water was included, a seasonal COP of 2.25 was obtained. As indicated above, this is a relatively conserva- tive estimate. Some manufacturers have options available to specifically adopt their units to low water temperature applications. Such units may give higher COPs. The 0&M labor requirements for the five alternative heating methods for the 10-year period 1981 to 1990 are shown in Table 6.4. Both types of electri- cal resistance heating are relatively maintenance free. Two hours of mainte- nance time is assumed after 10 years. Oil-hydronic heating system are assumed to require an annual maintenance check requiring 1.5 hours of time. In years 1985 and 1990 it is assumed that an additional 1.5 hours are required for mis- cellaneous repairs. There is little data available on the long-term mainte- nance requirements for ASHPs and even less for WSHPs. It is assumed that TABLE 6.4. O&M Labor Requirements for Residential Heating Systems, 1981-1990 (man-hrs) Electrical Resistance (Both Types) 0il-Hydronic ASHP. WSHP 1981 -- 1.5 -- -- 1982 -- 1.5 2.0 2.0 1983 -- 1.5 -- -- 1984 -- 1.5 -- -- 1985 -- 3.0 4.0 4.0 1986 -- 1.5 -- -- 1987 -- 1.5 2.0 2.0 1988 -- 1.5 -- -- 1989 -- 1.5 -- -- 1990 2.0 3.0 4.0 4.0 6.6 both types of heat pump will require a system recharge every 2 or 3 years requiring 2 hours of time with 2 hours of additional maintenance required in 1985 and 1990. The costs of purchasing and installing the WSHP heating system for the residence were discussed and presented in Section 5.4.1. These costs are sum- marized and the equivalent annual investment costs are presented in Table 6.5. TABLE 6.5. WSHP Heating System Purchase and Installation Costs and Equivalent Annual Investment Costs - Mendenhall Valley Residence Total Useful Annual Cost Life Cost Item ($) (yrs) ($/yrs) | Total System Less Compressor 13,400 25 1,592 Compressor 1,600 10 272 Total 15,500 -- 1,864 The purchase prices and annual investment costs for the comparable heating systems are presented in Table 6.6. The life-cycle cost calculations for the alternative heating systems eval- uated for this case are presented in Appendix D; Tables D.6 through D.10. The results of those calculations (the levelized annual costs) for the five alter- native heating systems are summarized in Table 6.7. As shown in Table 6.7, WSHP heating costs are comparable to electrical resistance heating costs. ASHPs offer the lowest heating costs while oil-hydronic heating is the most costly. The reasons for these results are discussed in the following paragraphs. WSHPs have the lowest energy cost of any of the alternatives considered. They use electricity which has a lower energy cost than fuel oil and they use it more efficiently to heat than either electrical resistance or ASHPs. WSHPs O&M costs are expected to be moderate compared to other heating methods. Electrical resistance heating features very low O&M costs while oil- hydronic has the highest 0& costs. It is important to keep in mind, however, that in the event of a major component failure both types of heat pumps would 6.7 TABLE 6.6. Purchase Price and Annual Equivalent Investment Cost for Alternative Heating Systems - Mendenhall Valley Residence Labor Material Total Useful Annual Cost Cost Cost Life Cost Equipment Type _($) ($) ($) (yrs) ($/yr) A. Electric ‘Baseboard 1850 900 2750 25 327 (Electrical Resistance) B. Electric Baseboard 1850 1560 3410 25 405 (Fluid Filled Electrical Resistance) C. Oil-Hydronic 1600 2400 4000 25 475 Furnace D. Air to Air Heat Pump Compressor -- 1000 1000 10 170 Supplemental heater, 1200 1800 3000 25 356 air handler, and controls Ductwork 1200 1800 3000 25 356 Total 2400 4600 7000 -- 882 Source: (CH2M 1980, p. 10) and discussion with Mel Dehart (Jack's Plumbing and Heating) and Steve Winters (Winters Electric), April 7, 8, and 9th. TABLE 6.7. Levelized Costs for Alternative Heating Methods - Mendenhall Valley Residence Direct Electrical Resistance $2921 Fluid-Filled Electrical Resistance 2999 0i1-Hydronic 4495 Air Source Heat Pump 2283 Water Source Heat Pump 3092 probably be the most expensive to fix. Such an event would probably give them the highest O&M costs. It is important that the initial design and installa- tion of heat pump heating systems be done properly to reduce the possibility of a later major component failure. 6.8 WSHPs have the highest purchase and installation cost and as a result have the highest annual investment cost. For this case the purchase and installation cost for the WSHP heating system is about twice as expensive as the ASHP heating system. There are three primary reasons for this. Firstly, WSHPs require larger air ducts because they have no electrical resistance supplemental heating and, thus, must circulate more lower temperature air at design heating conditions than ASHPs. Secondly, WSHPs require a relatively expensive water supply and disposal system. Thirdly, WSHPs are a relatively new heating system and are not manufactured in the quantities that ASHPs are. This typically results in higher manufacturing costs. Electrical resistance systems have the lowest purchase and installation costs. Oil-hydronic systems also have a relatively low purchase and installa- tion cost compared to heat pump systems The levelized costs shown in Table 6.7 will vary, of course, if different assumptions are made that would change the energy costs, the O&M costs, or the annual investment costs. While it would be interesting to see how the costs would vary under alternate assumptions, it is unlikely that the rank ordering of the heating costs would change greatly. While WSHP costs could possibly be lower than either type of electrical resistance heating system under some con- ditions, it is unlikely that WSHP heating costs could be lower than ASHP heat- ing costs or higher than heating costs for an oil-hydronic system. 6.2.2 Filter Building at the Auke Bay Laboratory In this case the heating costs for the existing forced air oil furnace are compared with the costs of heating the building with a WSHP. The costs are compared in two ways. In one case it is assumed that the decision to be made is whether to replace the existing heating system with a WSHP system. In this case the costs of installing a WSHP heating system are compared with the future O&M and fuel costs of the existing system. It is assumed that the existing heating system is paid off and has no salvage value. In the other case it is assumed that the decision is to be made for a new building that does not have an existing heating system. For this case total costs are compared as with the residential case. 6.9 A heating efficiency of 55% was assumed for the forced air furnace heat- ing system and a COP of 2.40 was used for the WSHP system. This COP assumes a COP of 3.0 excluding water pump energy requirements. When the water pumping energy is included, a seasonal COP of 2.40 is obtained. The O&M labor requirements for the filter building were assumed to be the same as for the residential case for the respective heating systems. The costs of purchasing and installing a WSHP heating system for this case were discussed and presented in Section 5.4.2. These costs are summarized and the equivalent annual investment costs are presented in Table 6.8. The pur- chase prices and annual investment costs for a forced air oil furnace are also presented in Table 6.8. TABLE 6.8. Heating System Purchase and Installation Costs and Equivalent Annual Investment Costs - Filter Building Labor Material Total Useful Annual Cost Cost Cost Life Cost Equipment Type ($) ($) ($) (yrs) ($/yr) A. WSHP System Total System Less Compressor -- -- 16,006 25 1,902 Compressor = = 1,984 10 338 Total -- -- 17,990 -- 2,240 B. Forced Ajr Furnace System Furnace (140,000 Btu/hr rating) -- 900 900 25 107 Ducting 1,400 400 1,800 25 214 Miscellaneous (oil tank fuel lines, controls) _400 _ 500 900 25 107 Total 1,800 1,800 3,600 25 428 (a) Source: Discussions with Juneau area heating contractors, April-May 1980. 6.10 The life-cycle cost calculations for the oil furnace and WSHP heating system are presented in Appendix D; Tables D.11 and D.12, respectively. The levelized annual costs for these two systems are presented in Table 6.9. TABLE 6.9. Levelized Annual Costs for Alternative Heating Methods - Filter Building Excluding Oil Including 0i1 Furnace Furnace Replacement Replacement Costs ($) Costs ($) Forced Air Oil Furnace 2780 3208 Water Source Heat Pump 3254 As shown in Table 6.9 the heating costs of the WSHP heating system are very similar to the heating costs for the forced air oil furnace heating systems. As with the Mendenhall Valley residence case the WSHP heating system has much lower energy costs than the oil-based heating system. The lower energy costs of the WSHP system are offset, however, by the much higher purchase and installation costs of the WSHP system. Excluding the oil furnace replacement cost results in the existing oil- based heating system having a lower life-cycle cost than the replacement WSHP heating system. Based on this analysis it would be less costly to retain the present heating system than to replace it with a WSHP heating system. It is interesting to compare the heating costs for the WSHP heating sys- tems and the oil-based systems for the Mendenhall Valley residence and the filter building. In the case of the residence, the heating costs for the oil-based system were considerably higher than the costs for the WSHP system ($4495 compared to $3092). In the filter building, on the other hand, the costs for the two systems are roughly comparable ($3208 for oi] heating and $3254 for the WSHP system). The basis for this difference in relative heating costs partially lies in the relative annual utilization of the heating system in the residence compared 6.11 to the utilization of the heating system in the filter building. WSHPs have high initial purchase and installation costs but low energy costs. They are more economically viable in applications having high utilization. Oil furnace heating systems have relatively low purchase and installation costs but rela- tively high energy costs. They will tend to be more economical in applica- tions having lower utilization. The residence has a design heat load of 49,000 Btu/hr with an annual heat- ing requirement of 183,917,000 Btu while the filter building with a higher design heat load of 57,000 Btu/hr has a lower annual heating requirement of 125,508,000 Btu. The reason for the relatively low annual heating requirement, in the case of the filter building, is that the outdoor design temperature for the filter building is -5°F compared to -15°F for the residence. It is assumed that the overall temperature distribution is 10°F higher at Auke Bay than in the Mendenhall Valley. This difference causes the filter building to have a lower annual heating requirement relative to the design heat load than the residence. 6.2.3 Warehouse on the Juneau Waterfront In this case the heating costs for the oi] hydronic heating system in the existing NMFS warehouse are compared with the costs of heating the building with a WSHP heating system. As explained in Section 5.4.3, three separate WSHPs are used in the design. As with the filter building case, the costs are compared in two ways: 1) assuming that a decision is being made whether to replace the existing heating system and 2) assuming a new building without an existing heating system. A heating system efficiency of 70% is assumed for the existing heating system. This is higher than the efficiency assumed for the residence and filter building (55%). The higher efficiency is assumed because of the larger size of the oi] boiler which should allow for more efficient operation. As with the previous cases a WSHP COP of 3.0 excluding water pumping energy is assumed. With the energy required for pumping the supply water, a system seasonal COP of about 2.3 is obtained. The O&M labor requirements for the two cases are shown in Table 6.10. 6.12 TABLE 6.10. O&M Labor Requirements for the Warehouse Heating Systems, 1981-1990 (man-hrs) Oil-Hydronic WSHP- 1981 3.0 5.0 1982 3.0 11.0 1983 3.0 5.0 1984 3.0 5.0 1985 6.0 17.0 1986 3.0 5.0 1987 3.0 11.0 1988 3.0 5.0 1989 3.0 5.0 1990 6.0 17.0 The O&M labor requirements are extrapolated from the 0&M requirements for the residential case with additional time included in the WSHP system for main- tenance of the chlorinator and sea water supply system. The O&M requirements for the oi] hydronic system were increased by a factor of 2 each year over the residential case. For the WSHP system it was assumed that annual routine main- tenance on the water supply system and the chlorinator system would require 5 hours. Maintenance on the WSHPs was assumed to be 2 hours per unit (a total of 6) during 1982 and 1987 and 4 hours per unit (a total of 12) during 1985 and 1990. Sodium hypochlorite will be used to provide chlorine for the chlorinator system. As discussed in Chapter 4 sodium hypochlorite costs about $17.45/ 6 gallons. Assuming a maximum water flow rate of about 54 gpm and that the system operates 9 months out of the year, sodium hypochlorite would cost about $165/year. The costs of purchasing and installing the WSHP heating system for the case were presented in Section 5.4.3. These costs are summarized and the equivalent annual investment costs are presented in Table 6.11. The cost and annual investment costs for an oi] hydronic heating system are also presented in Table 6.11. 6.13 TABLE 6.11. Heating System Purchase and Installation Costs and Equivalent Annual Investment Costs - Warehouse Total Useful Annual Cost Life Cost Equipment Type ($) (yrs) = ($/yr) A. WSHP System Total System Less Compressors and Water Pump 68,027 25 8,084 Compressors and Water Pump 11,973 10. 2,033 Total 80,000 -- 10,117 B. Oi] Hydronic ate Total System 30,000 25 3,565 (a) Battelle estimate based on discussions with Juneau area heating contractors, April-May 1980. The life cycle cost calculations for the oil furnace and WSHP heating system are presented in Appendix D; Tables D.13 and D.14, respectively. The results of these computations are shown in Table 6.12. TABLE 6.12. Levelized Annual Costs for Alternate Heating Methods - Warehouse Excluding 071 Including 071 Furnace Furnace Replacement Replacement Costs ($) Costs ($) 0il Hydronic System 7,590 11,155 Water Source Heat Pump System 13,749 6.14 As shown in Table 6.12 the levelized annual heating costs of the WSHP system are higher than the heating costs for the oil hydronic heating system ($13,749 compared to $11,155). While the WSHP system has lower energy costs, the higher annual investment costs more than offset this advantage. When the furnace replacement costs are not included the cost advantage of the existing oi] heating system is even greater ($7,590 compared to $13,584). It would not be justified from a cost standpoint to replace the existing heat- ing system with a WSHP system. 6.2.4 Salmon Hatchery Near Snettisham Hydroelectric Project This case compares the cost of heating a salmon hatchery with WSHPs to the cost of heating the building using electrical resistance heaters. The hatchery is presently under construction near the Snettisham hydroelectric project. The heating efficiency of the electrical resistance system is assumed to be 100%. A seasonal system COP for the WSHP system of 2.5 is used. As in the previous cases a COP of 3.0 is assumed excluding the water pumping energy required. When the water pumping energy is included the assumed system COP of 2.5 is obtained. The O&M labor requirements for the two heating systems are shown in Table 6.13. The electrical resistance heating system can be expected to be TABLE 6.13. O&M Labor Requirements for the Salmon Hatchery Heating Systems, 1981-1990 (man-hrs) Electrical Resistance WSHP 1981 -- -- 1982 -- 6.0 1983 -~ ail 1984 -- -- 1985 4.0 12.0 1986 -- -- 1987 -- 6.0 1988 -- -- 1989 -- -- 1990 4.0 12.0 6.15 relatively maintenance free. The 4 hours included in 1985 and 1990 would be for routine cleaning and for replacement of any possible defective or broken units. The WSHP system maintenance requirements are extrapolated from the residential case. Maintenance on the units was assumed to be 2.0 hours per unit during 1982 and 1987 and 4 hours per unit in 1985 and 1990. The costs of purchasing and installing the WSHP heating system were presented in Section 5.4.4. These costs are summarized and the equivalent annual investment costs are presented in Table 6.14. The costs for the planned electrical resistance heating system are also shown in Table 6.14. The cost calculations for this case are presented in Tables D.15 and D.16. The results are shown in Table 6.15. As shown in Table 6.15 the levelized annual heating costs for the electrical resistance heating system are less than the heating costs for the WSHP system. The difference (about 8%) is relatively small, however. TABLE 6.14. Heating System Purchase and Installation Costs and Equivalent Annual Investment Costs - Salmon Hatchery Total Useful Annual Cost Life Cost Equipment Type ($) (yrs) | ($/yr) A. WSHP System Total System Less Compressors and Water Pump 60,775 25 7222 Compressors 8375 _10 1423 Total 69,150 -- 8645 B. See riay Resistance System\4@ Total System $46,500 25 $5,526 (a) Cost estimate from Haskell Corp. Bellingham, WA. Discussion with Ed Frere of the Haskell Corp. Bellingham, WA. (May 1980). The Haskell Corp. is the mechanical subcontractor on the building. 6.16 TABLE 6.15. Levelized Annual Costs for Alternative Heating Methods - Salmon Hatchery Electrical Resistance System $9,640 Water Source Heat Pump System $10,516 Electrical resistance heating is attractive for the salmon hatchery because of the relatively low electrical rates available there. The relative economics would be much closer or perhaps the WSHP would even be less expen- sive if the electrical rates were similar to those in Juneau. 6.3 TECHNICAL VIABILITY OF WSHPs IN THE JUNEAU AREA The purpose of this section is to evaluate the technical viability of the 4 WSHP heating system designs presented in Chapter 5. Since WSHP heating sys- tems have much in common regardless of the specific application, the majority of the discussion in this chapter relates to WSHP applications in general (Section 6.3.1). The technical viability of the 4 specific cases are then evaluated and summarized in Sections 6.3.2 through 6.3.5. 6.3.1 General Considerations The most important factor necessary for a successful WSHP installation is availability of a water supply with acceptable temperature, quality, and quan- tity. One manufacturer's experience indicates that about 42% of the field problems associated with installations of their equipment were due to improp- erly designed, installed or maintained water systems. Only about 3% of the field problems were due to faulty WSHP equipment (Wescorp 1980, p. 22). Since the availability of both sea and ground water suitable for use in a WSHP is dependent upon the specific location of the structure to be heated, no overall conclusions can be drawn for the Juneau area. However, it appears that in a number of locations there is ground water suitable for use as a heat source for WSHPs. Information contained in the report Hydrologic Data of The Juneau Borough, Alaska (McConaghy 1969, pp. 57-59) indicates that ground water 6.17 temperatures in the 40 to 46°F range are not uncommon in the Juneau area. As shown in Figure 4.1 sea water temperatures of at least 38°F are available all year in the Auke Bay area. Similar temperatures should be available in the deeper portions of the Gastineau Channel immediately in front of the down- town Juneau area. The COP and heating capacity of WSHPs vary with the inlet water tempera- ture. The COP of one model of a WSHP designed for low water temperature appli- cations over the temperature range from 40 to 62°F is shown in Figure 6.1. As shown the COP varies from about 2.7 at 40°F to about 3.6 at 62°F (inc lud- ing nominal pump allowance). = 3.5 2 @ > = < 3.0 < a. Oo 5 S = = Ss 2.5 = 1 l 1 L 4 40 45 50 55 60 65 INLET WATER TEMPERATURE (OF) FIGURE 6.1. Coefficient of Performance and Heating Capacity Versus Inlet Water Temperature for Example WSHP Source: Performance specifications for Thermal Energy Transfer Cor- poration (TETCO) Model HECWE-050 for 12 gpm water flow rate and 1000 cfm air flow rate. Heating capacity for the unit varies from 58,400 to 44,000 Btu/hr over this temperature range. 6.18 To operate at such relatively low temperatures water source heat pump installations will require relatively high water flow rates. In general, a constant water flow rate of 15 to 20 gallons per minute (gpm) should be avail- able for units in the 50,000 to 60,000 Btu/hr size and about 30 to 40 gpm for units in the 100,000 Btu/hr range. Residential heating using WSHPs requires relatively high water flow rates and water quantities compared to normal residential domestic water needs. A typical residence requires a peak flow rate of 5 to 15 gpm depending upon the house size, family size, and number of fixtures. A WSHP requiring 15 gpm would increase the maximum required water flow rate by 100 to 300%. A home normally requires from 50 to 100 gallons per day (gpd) per resi- dent for domestic needs (200 to 400 gpd for a family of 4). A WSHP using 15 gpm would need 21,600 gpd. While this maximum flow rate would be required only when the heat pump was operating at peak capacity, large quantities of water are required for WSHPs relative to normal domestic needs. Because of the high water quantity and flow rates required, the water supply in any new building should be specifically designed for a WSHP. The water supply system in any prospective retrofit should be evaluated and modi- fied if necessary to provide an adequate water flow rate. A method of water disposal is also required with WSHP installations. In most applications using ground water an additional disposal well is probably the best method of disposing of the effluent water. In cases using sea water the most obvious disposal method is to return the water to the ocean or bay. In the case of ground water the water disposal wells should be located some distance from the supply well and from other WSHP supply wells to insure that the cooled water is either not reused in the heat pump or has sufficient time to be warmed by the ground and surrounding water before reuse. Unfortu- nately, it is very difficult to predict what the minimum spacing should be. Well spacing depends upon a number of factors including length of the heating season, heat load, water flow rate, ground water temperature, and aquifer porosity. Minimum well spacing must be evaluated on a case-by-case basis. The only case evaluated in this report that involves the use of a well is 6.19 the Mendenhall Valley residence. It is beyond the scope of this project to determine the necessary well spacing for the Mendenhall Valley area. For the purposes of this study a well spacing of 75 ft. is assumed. Disposal wells should typically be larger than the supply well to insure adequate flow. A common rule of thumb is to design the disposal well to have twice the capacity of the water supply wel). (2) Any applicable federal, state, and local regulations concerning the use of ground or sea water should be investigated. There do not appear to be any restrictions to the use or disposal of ground water in the Juneau area but there are federal and state regulations concerning the extraction and disposal of sea water. One problem encountered in the use of low temperature water is the danger of the cooled outlet water freezing in the discharge piping. The effuent water will be in the 34 to 36°F range as it leaves the heatpump unit. Of course, the greatest danger of this happening is during the coldest times of the year when space heating is most necessary. Precautions must be taken to insure this will not happen. This can be accompolished by burying the pipes below the frost line and/or insulating the pipe. The problems of using sea water as a heat source and some possible solu- tions to them were discussed in Chapter 4. No significant problems that would prevent the use of sea water were disclosed in this analysis. No unusual water quality problems should prevent the use of ground water. One problem that is relatively common in ground water supply systems is calcium carbonate scaling. Calcium carbonate is present at some levels in all ground water. The amount of calcium carbonate dissolved in water is determined to a large extent by the amount of carbon dioxide in the water. Scaling problems occur when the condition of the water is changed to reduce the amount of carbon (a) Presentation titled "Ground Water Geothermal Heat Pump Disposal Methods" given by Richard L. Shockley, President of Delta Well Co. Inc. at The National Ground Water Geothermal Heat Pump Conference and Exposition, Columbus, Ohio, February 11, 1980. 6.20 dioxide and, hence, the amount of calcium carbonate dissolved in the water. Heating or reducing the pressure of water reduces the amount of carbon dioxide dissolved in water. Since the water flowing through WSHPs during the heating cycle is cooled, there is little danger for scaling in heating only applica- tions. The use of pumps which draw a vacuum may promote calcium carbonate scaling since the pressure in the intake line is reduced. In general, perhaps the best way to learn if there will be water quality problems in a particular application is to see if there are any problems with other water systems in the area. Heat pump installations (both air and water heat source) require higher interior air circulation rates than oil fired forced air heating systems since they have a lower temperature heat source. The source of heat in an oil fur- nace is a flame with a temperature in the 1000 to 2000°F range while the source of heat in a heat pump is compressed refrigerant with a temperature of about 130 to 150°F. For this reason heat pump installations require larger air ducts to circulate more air to provide the same amount of heat as forced air oil furnaces. It is important to keep this fact in mind when considering retrofitting an existing structure with an oi] furnace heating system with a heat pump. It is unlikely that the existing air ducting system designed for an oi] furnace will be adequate for a heat pump installation. In addition to the availability of a suitable water supply the other pri- mary factor necessary for a successful WSHP application is proper installation and maintenance. In general, heat pump heating systems (both air and water heat source) are much more complex than electric resistance or oil heating systems. In some ways WSHPs are more complex than ASHPs since they require a water heat exchanger and the associated water supply and disposal systems rather than an air heat exchanger. Because of the more complex water supply and disposal system associated with WSHP systems they require more careful design, installation, and maintenance than ASHPs. Because WSHP heating systems are not as common as other methods of heat- ing, there are not many distributors or engineering firms with a great deal of experience in their design or installation. However, information is available from distributors, manufacturers, trade associations, and the open literature 6.21 that would allow most mechanical and/or heating contractors to properly design and maintain WSHP heating systems. Initially it will be especially important to purchase units from manufacturers and distributors who will provide good delivery, installation, and warranty service in the Juneau area. 6.3.2 New Residential Construction in the Mendenhall Valley This installation reflects standard current practice for WSHPs in resi- dences. The low water temperature requires a relatively high water flow rate but these flow rates are well within standard residential practice. There should be no major technical problem associated with this installation. 6.3.3 Filter Building at the Auke Bay Laboratory This installation involves the use of a residential sized WSHP utilizing sea water as a heat source. Any major technical problems associated with this installation will probably be associated with the use of sea water. These problems are discussed in Chapter 4.0. The sea water at the Auke Bay laboratory is sent through a sand filter to remove the majority of the biological fouling organisms before use. Thus, the water used in the heatpump will be filtered. As a result, biological fouling should not be a problem in this installation. The low temperature water available at Auke Bay well require relatively high water flow rates at design conditions (up to 17 gpm). This should not present a technological problem since such flow rates are common in many resi- dential and small commercial operations. 6.3.4 Warehouse on the Juneau Waterfront The technical considerations of this case are similar to those of the fil- ter building case since both systems are using sea water. In this case, how- ever, a chlorinator is used to eliminate biological fouling rather than a sand filter. The use of chlorinators for WSHP applications were discussed in Chapter 4.0. 6.3.5 Salmon Hatchery In this case there should be no problems with the technical viability of the WSHP heating system. Fresh water is used as the source of heat so there shouldn't be any problems with corrosion or fouling. 6.22 6.4 EFFECTS ON ELECTRICAL AND FOSSIL FUEL USAGE The annual oil and electricity consumption for the alternative heating methods evaluated in this report are presented in Table 6.16. Use of WSHPs for heating in the Juneau area could reduce the use of fossil fuels while increasing the use of electricity. However, the increase in electricity use would be relatively low compared to electrical resistance heating since WSHPs offer seasonal COPs from 2.25 to 2.5. Substituting a WSHP for a oil-hydronic furnace in the typical residential example case would increase electrical con- sumption by about 24,000 kWh per year, while reducing oi] consumption by about 2412 gallons per year. Substituting a WSHP for electrical resistance heating in the residential case would reduce the electricity consumed for heating from about 54,000 kWh per year to about 24,000 kWh per year. As mentioned earlier in Chapter 2, the energy consumption estimates for the residence are similar to estimates for Juneau area residences contained in other recent studies (AEA 1979, p. 99 and CH2M Hill 1980, Appendix Table 8). These estimates are higher than the average "all electric" residential consump- tion of 24,216 kWh derived from 1977 electrical consumption data for the Juneau area (AEA 1979, p. 14). There are several possible reasons for computed estimates to be higher than actual data suggests. They include: TABLE 6.16. Annual Oil and Electricity Consumption for Alternative Heating Methods Electrical Resistance 0i1 Heat ASHP WSHP (Electricity) (Fuel Oi1) (Electricity) (Electricity) ___(kWh) (gal) (kWh) (kWh) Residence 53,875 2412 28,114 23,949 Filter Building -- 1645 -- 15,195 Warehouse -- 4853 -- 60,028 Salmon Hatchery 205,033 -- -- 82,013 6.23 e The assumption is made in the calculated estimates that the house is heated to 70°F at all times. In actual practice the interior tem- perature may be reduced in portions of the house when not in use or in the entire house during evening and nighttime hours. e In many cases in Juneau there is supplemental wood heat. The use of wood heat would also tend to reduce the actual consumption below the calculated estimates. e The size and location of the houses included in the electrical con- sumption survey may not be representative of a new residence in the Mendenhall Valley. The Mendenhall Valley has a lower design tempera- ture than areas closer to sea water. e The quality of the insulation may be different in the homes used in the survey than the quality of the insulation assumed in the com- putated estimates. This probably would be a minor factor, however, since the residence in this report was relatively well insulated. In the case of the Filter Building a WSHP would eliminate the use of oil for heating (1645 gal/yr) while increasing electrical consumption by 15,195 kWh/yr. In the warehouse case a WSHP heating system would reduce oi] consump- tion by 4853 gal/yr. For the case of the Snettisham salmon hatchery use of a WSHP heating system would reduce electrical consumption from 205,033 kWh to 82,013 kWh. 6.24 REFERENCES - Chapter 6.0 Applied Economics Associates, Inc. March 1979. The Role of Electric Power in the Southeast Alaska Energy Economy. Prepared for the Alaska Power Admini- stration, Juneau, Alaska. CH2M Hill. 1980 A Comparison of Home Heating Costs: Electricity Versus Oil. Prepared for the Glacier Highway Electric Association, Auke Bay, Alaska. McConaghy, J. A. 1969. Hydrologic Data of the Juneau Borough, Alaska. Pre- pared by United States Geological Survey in cooperation with the Greater Juneau Borough. Wescorp Company. 1980. Procedures and Responsibilities for Normal and Extra- ordinary Maintenance of the Ground Water Seothermal Heat Pump. Andover, MA. 6.25 7.0 RECOMMENDATIONS FOR VERIFICATION PROGRAM AND ADDITIONAL RESEARCH EEA ANU ADDITONAL RESEARCH As pointed out in the introduction, the purposes of this project and report are to evaluate the technical and economic viability of WSHPs for use in the Juneau area and to identify potential verification projects. The pur- pose of this chapter is to present recommendations for a program to verify the results of the analyses contained in this report and to make some recommenda- tions for further data gathering. 7.1 RECOMMENDATIONS FOR VERIFICATION PROGRAM Based upon these analyses it appears that WSHPs are technically and eco- nomically viable in the Juneau area. There does not appear to be any technical problem involved in their use with either fresh or sea water which would pre- vent their use. And as discussed in Chapter 6, WSHP heating systems offer life cycle heating costs that are generally comparable or slightly higher than other types of heating available in the Juneau area. However, because of the rela- tively low water temperatures, possible fouling and corrosion problems associ- ated with the use of sea water, and uncertainties about the availability of proper design and maintance in Juneau, a field demonstration program to verify the results of this report should be conducted before a final recommendation is made as to the viability of WSHPs in the Juneau area. A residence in the Mendenhall Valley similar to the residential application evaluated in this report would probably be a good fresh water application although any residence either new or existing with an acceptable water supply should work just as well. For the sea water demonstration an industrial or commercial building located near the water front similar to the NMFS warehouse would be a logical choice. A successful demonstration program should include the following factors: 1. A building located near a supply of fresh or sea water of acceptable temperature, quality, and quantity. 2. A qualified design engineer with a good knowledge of all aspects of WSHP practice. He should have a knowledge of both fresh and salt water piping and pumping applications in the Juneau area. 7.1 3. A high quality WSHP of the correct size and specifications as well as quality components throughout the system. 4. It will be important for the heat pump manufacturer and distributor to be interested and supportive of the project. Since there are presently no distributors of WSHPs in the Juneau area it will be necessary to work with a distributor in the lower 48 (preferably in the Northwest). 5. A maintenance and field service program. 6. Proper instrumentation to monitor the performance of the demonstra- tion units. 7. A data collection and analysis program to compile and evaluate the data. 8. It will be necessary to find out what federal, state and local, legal, environmental and regulatory restrictions there are on the use of fresh and sea water. There do not appear to be any state or local restrictions to the use of fresh water but there are federal and state restrictions on the use of and discharge into sea water. 9. A project manager to coordinate the overall program. Each of these factors are briefly discussed below. As discussed in Section 6.3, a key factor in any successful WSHP installa- tion is a water supply with the proper temperature, quality, and flow rate. In the case of a fresh water demonstration site the minimum temperature should be 40°F with a 42 to 45°F supply preferable. The temperature should be moni- tored to insure that it remains above 40°F all year. The flow rate available depends upon the specific WSHP brand that is to be installed. As pointed out in Section 6.3, a constant flow rate of at least 15 gpm should be available for units in the 50,000 to 60,000 Btu/hr size range (typical residential size). A constant water flow rate of about 30 gpm would be necessary for units in the 100,000 Btu/hr range. 7.2 Another key factor for a successful WSHP installation is a well engineered system. Because WSHP heating systems are not common at this point there are not many distributors or engineering firms with a great deal of experience in their design or installation. However, information is available from distribu- tors, manufacturers, trade associations and in the open literature that would allow most mechanical and/or heating engineering firms to design WSHP heating systems. A knowledge of sea water piping and handling techniques would be nec- essary to design a sea water system. Before proceeding with any demonstration project an engineer should pre- pare a detailed engineering design and cost estimate. The design work done as part of this project is on a feasibility level and should not be used for final design or cost estimating. It will be especially important to purchase high quality units from manu- facturers and distributors who will give good delivery and warranty service. They should be willing to work with the APA, the customer, and the design engi- neer to provide information for the design. If possible there should be a com- pany distributor or serviceman either in Juneau or available on short notice. In order to evaluate the performance of a WSHP field demonstration the installation should be properly instrumented. The following monitoring equip- ment should be installed. 1. A separate electrical meter for the WSHP and water pump. - Thermometers measuring the inlet and outlet water temperature. An indoor and outdoor thermometer. A method of measuring the air flow through the air handler. an P WwW PY A thermometer to measure the inlet and outlet air temperatures. Data should be collected to allow the energy cost and COP of the units to be computed. This requires measuring the energy input (the electrical meter) and the heat output. The heat output can be determined either by knowing the air flow rate and temperature increase of the air going through the air handler or by knowing the heating requirements for the building. The building heating requirements can be determined from the indoor and outdoor temperatures and a heat load analysis of the building. 7.3 As mentioned above, there are state and federal restrictions and permits required for the use and disposal of sea water as well as for the construction of intake and effluent systems. The U.S. Environmental Protection Agency (EPA) administers The National Pollutant Discharge Elimination System (NPDES) that was established by the Federal Clean Water Act. Under the NPDES any system disposing of sea water must have a permit if a pollutant or heat is. added to the water. It is not clear whether an application that would cool the water such as heat pump would be classified as heat pollution or not. Certainly any system adding a biocide such as chlorine would be covered under NPDES standards. Under Section 401 of the Federal Clean Water Act, the individual states must issue a permit stating that the prospective application meets applicable NPDES regulations before the EPA will issue a federal permit. The Alaska State Department of Environmental Conservation administers NPDES Section 401 for the state of Alaska. The southwest regional office of the Department of Environ- mental Conservation would be the first place to contact regarding a WSHP appli- cation using sea water. Questions regarding the NPDES could also be directed to the Seattle regional office of the EPA. Any use of tidelands within the state requires a permit from the Alaska state Department of Natural Resources--Tidelands and Water Resource Office. Any dredging or filling would require a permit from the U.S. Corps of Engi- neers. Under Section 401 of the Clean Water Act the state would have to first issue a permit saying the dredging or filling meets the provisions of the NPDES. Because of the great number of details associated with such a project a project manager should be assigned to facilitate the design, installation, and monitoring program. 7.2 RECOMMENDATIONS FOR ADDITIONAL RESEARCH In the process of gathering data for this report, two additional applica- tions of WSHPs, for space heating in Juneau and southeast Alaska were consid- ered but not selected for further evaluation. One involves the use of WSHPs for district heating while the other involves the use of water from wells to heat buildings located in downtown Juneau. 7.4 While there are many possible configurations for district heating with WSHPs, one that may be attractive for Juneau and other communities in south- east Alaska would use a large commercial size WSHP located close to sea water and smaller individual units located in the buildings to be heated. The large water to water heat pump would use sea water as a heat source and would heat a secondary circulating water supply. The secondary supply would be circulated through a piping system to the individual buildings. Each building would have a WSHP which would use the heated circulating water as a heat source. The water in the circulating loop would be maintained at about 50-60°F and as a result the individual WSHPs could operate with relatively high COPs with rela- tively low water flow rates. Since the central WSHP would be located close to sea water the problems and cost associated with salt water fouling and corrosion could be kept to a minimum. The system would also be large enough to allow trained maintenance men to be available at all times to maintain the central heat pump as well as the units in the individual buildings. The operation of such a district heat- ing system would be similar to an electrical or water utility. This would not only allow for a good maintenance program, as mentioned above, but could also allow the system to be financed using municipal financing methods which typi- cally have lower interest rates than private financing methods. Such an arrangement could significantly reduce the cost of building a district heating system. Further evaluation would be necessary to see if such a system is tech- nically or economically feasible in southeast Alaska. The other application would use water from shallow wells to heat buildings located in downtown Juneau. A large part of downtown Juneau is located on tailings from the Treadwell mines. These tailings are unconsolidated and very porous. In fact, the water level under many areas rises and falls with the tide. (2) This indicates that there should be ample water available for WSHP s as well as good possibilities for a water disposal. Because of the apparent high natural flow rate the cooled effluent water should be quickly dispersed. (a) Discussions with John Spietz, City and Borough of Juneau, March 13, 1980. 7.5 The temperature and extent of this resource should be investigated. Since the water flows through the ground it may pick up additional heat from the earth. If it appears that the water is of an acceptable temperature and qual- ity a feasibility level study should be undertaken to evaluate this as a water source for space heating in Juneau. 7.6 APPENDIX A ADDITIONAL INFORMATION FROM WATER SOURCE HEAT PUMP MANFACTURER SURVEY APPENDIX A ADDITIONAL INFORMATION FROM WATER SOURCE HEAT PUMP MANUFACTURER SURVEY This appendix contains addresses of Northwest Distributors and factory representatives of water source heat pumps reviewed in this report. Also included is a representative price list of water-to-air heat pumps by heating capacity and brand. Thirteen of the nineteen brands of heat pumps reviewed in this report have Northwest Distributors or factory representatives (Table A.1). Northwest Dis- tributors were located in the Seattle and Portland areas with the exception of one in Eugene, Oregon. In some cases there are both Seattle and Portland Dis- tributors for the same heat pump brand. In most cases the Seattle Distributor was listed rather than the Portland Distributor. However, there appeared to be more Heat Pump Distributors in Portland than in Seattle. The price-capacity chart (Table A.2) provides representative prices of water source heat pumps. This table should not be used for comparing prices between brands. Instead, it should be used to illustrate the range of costs for a given capacity. Prices are very sensitive to system options, operating conditions, and capacity. For heat pump selection, more detailed price infor- mation including shipping costs and sales tax should be sought. A.l TABLE A.1. Distributor Airefco Inc. 13405 S.E. 30th St. Suite 1A Bellevue, WA 98005 206-747-5911 Airtec Co. 1000 1st St. Seattle, WA 98104 206-623-2374 Brod and McClung-Pace Co. 9800 S.E. McBrod Milwaukie, OR 97222 503-659-5880 Day-York 2135 S.E. Ochoco Portland, OR 97202 503-234-0608 Enviro Air Systems P.O. Box 4445 Portland, OR 97208 503-223-5114 Hardesty & Company, Inc. 220 South River St. Seattle, WA 98108 206 -767 -3083 Brands Carrier Friedrich Command-Aire Solargy York Hydrobank Comf ort-Aire/Century (Heat Controller) Distributor Pameco-Aire 1209 Mercer Seattle, WA 98109 206-624-3200 Peerless Pacific 555 N. Thompson Portland, OR 97227 503-287-1888 Pitcher Pump 87829 Greenhill] Rd. Eugene, OR 97402 503-484-5014 R. D. Morse Co. 2366 Eastlake Ave. E. Suite #436 Seattle, WA 98102 206-329-5403 Hal Teasley & Associates 2700 S.£. Ankeny Portland, OR 97214 503-231-4972 THE FOLLOWING MANUFACTURERS DO NOT HAVE NORTHWEST DISTRIBUTORS American Air Filter Co. Inc. 215 Central Ave. Louisville, KY 40277 Distributed by NESCO Inc. P.O. Box 234 Monroe, NC 28110 704-289-6431 Conservation Technologies Inc. 13375 U.S. 19 South Clearwater, FL 33520 813-531-7741 International Energy Conservation Systems Inc. 1775 Central Florida Parkway Regency Industrial Park Orlando, FL 32809 305-851-9410 Phoenix Air Conditioning Inc. 651 Vernon Way El Cajon, CA 92020 714-579-3884 Enercon Convectionaire TempMaster Enviro-Temp A.2 “Solar-Oriented" Environmental Systems Inc. 10639 S.W. 185th Terrace Miami, FL 33157 305-233-0711 Distributed by Spectrum Solar Systems Corp. M Center St. Pickerington, OH 43147 617-837-5159 Vanguard Energy Systems 9133 Chesapeake Drive San Diego, CA 92123 714-292-1433 Distributed by Trendsetter Industries 9484 Chesapeake Drive Suite 862 San Diego, CA 92123 714-268-3862 Northwest Distributors of Water-to-Air Heat Pumps Brands KoldWave (Heat Exchangers) Energy Miser (Florida Heat Pump) TETCO Whalen Singer Northrup SOESI/SERCO Vanguard TABLE A.2. Price-Capacity Chart by Brand(a) : Heating Capacity (1000 BtuH) _ UTIL Brand 20-30 30-40 40-60 60-90 90-150 150-200 200-300 300-400 Carrier 1380 1804 Century 813 1024 1612 1847 Comfort-Aire 3775 6020 7723 12,090 Command-Aire Convectionaire Enercon 1702 2126 2882 Energy Miser 1382 1545 1964 3124 5754 11,796 Enviro-Temp 2900 3289 4069 4460 Friedrich 1840 2660 Hydrobank 1226 1681 1707 3648 4225 KoldWave 1239 1352 1628 2457 3354 Northrup Singer SOESI Solargy TempMaster 3000 3263 4281 6063 9700 10,981 18,300 23,000 TETCO 1950 Vanguard 2814 3418 3895 5105 Whalen York 1300 1450 2000 (a) This table gives approximate retail prices supplied by distributors. No trans- poration costs are included. In some cases, there are several models of a par- ticular brand that fall into the capacity range of a single column. In these cases, the model closest to the center of the range was choosen. In addition, prices for different brands reflect different system options and electrical characteristics. When only dealer prices were available, a 25% Markup was included. These factors should be considered in reviewing these prices. A.3 APPENDIX B HEAT LOAD CALCULATIONS Td TABLE B.1. Heat Load Calculations for Residence Outdoor Design Temperature = -15°F Design Temperature Difference = 85°F Interior Design Temperature = 700F Total Heat Load = 48,401 Btu/hr Family, Hall "A" Bath "A" Mechanical et rea or Area or Area or No. HTM Length BtuH Length _BtuH Length BtuH Gross Exposed 12C 75 40 Walls & 13j 45 Partitions lle 56 48 40 10g 136 Windows & 2b 80 21 1680 5 400 Glass Doors 4b 75 7b 105 40 4200 Other Doors 9d 98 20 1960 Net Exposed 12c 11 75 825 35 385 Walls & 13j 3.6 45 162 Partitions lle 7 36 252 48 336 40 280 10g 3.4 75 255 Ceilings 143 2.1 Special ey, Floors 20b 55 32 1760 5 275 17e 3.8 Subtotal BtuH Loss 287 11094 30 1396 25 280 Duct BtuH Loss Total BtuH Loss 287 11094 30 1396 25 280 (a) From ACCA Manual J. Table 2 (ACCA 1975, p. 31-33). Heat Loss and Heat Gain Calculation Worksheet format from (ACCA 1975, p. 13). 2°d Const. No. (4) Gross Exposed 12C Walls & 13j Partitions lle 10g Windows & 2b Glass Doors 4b 7b Other Doors 9e Net Exposed 12c Walls & 13j Partitions lle 10g Ceilings 143 Special Floors 20b 17e Subtotal BtuH Loss Duct BtuH Loss Total BtuH Loss HTM 80 75 105 Pr WwNwr ee . . > oa wn . Ne (contd) TABLE B.1. Studio Area or Length BtuH 137 82 40 16 1280 121 1331 82 295 40 280 27 1485 168 4671 168 4671 Worksheet format from (ACCA 1975, p. 13). (a) From ACCA Manual J. Table 2 (ACCA 1975, p. 31-33). Master/Dressing Area or Length BtuH 255 30 2400 225 765 210 441 210 798 210 4404 0.2 881 210 5285 Bath "B" Area or Length BtuH 45 95 35 133 45 228 0.2 46 45 274 Heat Loss and Heat Gain Calculation e"d Gross Exposed Walls & Partitions Windows & Glass Doors Other Doors Net Exposed Walls & Partitions Ceilings Floors Subtotal BtuH L Duct BtuH Loss Total BtuH Loss 9e 12c 13j lle 10g 143 Special 20b 17e oss TABLE B.1. (contd) Bath "C" Kitchen Dining Area or Area or Area or HTM Length BtuH Length BtuH Length BtuH 32 80 176 80 5 400 21 1680 75 105 40 4200 191 11 3.6 7 3.4 127 92 59 201 136 462 ack 24 50 120 252 120 252 1.7 55 3.8 . 12 46 24 588 120 2133 120 4914 0.2 118 24 706 120 2133 120 4914 (a) From ACCA Manual J. Table 2 (ACCA 1975, p. 31-33). Worksheet format from (ACCA 1975, p. 13). Heat Loss and Heat Gain Calculation va TABLE B.1. (contd) Living Room Entry & Hall "C" Hall "B" Const. Area or Area or Area or No. (2) HTM Length _Btud Length Btu _—_Length —_ Btu Gross Exposed 12C Walls & 13j Partitions lle 58 10g 248 123 Windows & 2b 80 =——s«i20 1600 Glass Doors 4b 75 13 975 13 975 7b 105 Other Doors 9e 191 20 3820 Net Exposed 12c 11 Walls & 13j 3.6 Partitions lle 7 58 406 10g 3.4 215 731 90 306 Ceilings 143 2.1 116 244 64 134 60 126 Special 1.7 116 197 47 80 Floors 20b 55 17e 3.8 110 418 60 228 Subtotal BtuH Loss 210 3747 104 6139 60 354 Duct BtuH Loss 0.2 1228 0.2 71 Total BtuH Loss 210 3747 104 7367 60 425 (a) From ACCA Manual J. Table 2 (ACCA 1975, p. 31-33). Heat Loss and Heat Gain Calculation Worksheet format from (ACCA 1975, p. 13). Ne sa Const. No. (4) Gross Exposed 12C Walls & 13j Partitions lle 10g Windows & 2b Glass Doors 4b 7b Other Doors 9e Net Exposed 12c Walls & 13j Partitions lle 10g Ceilings 143 Special Floors 20b 17e Subtotal BtuH Loss Duct BtuH Loss Total BtuH Loss HTM 80 75 105 191 RPP wNswor oe . ° Ne - a wn co TABLE B.1. (contd) Bedroom 2 Bedroom 3 Total House Area or Area or Area or Length BtuH Lenath BtuH Length BtuH 216 128 15 1200 15 1200 199 677 113 384 158 332 128 269 158 600 113 429 158 2809 128 2282 1689 45039 0.2 562 0.2 456 3362 158 3371 128 2738 1689 48401 31-33). Heat Loss and Heat Gain Calculation (a) From ACCA Manual J. Table 2 (ACCA 1975, p. Worksheet format from (ACCA 1975, p. 13). TABLE B.2. Heat Load Calculation Data for Residence Ceiling - Wood trusses @ 16" OC, 12" fiberglass insulation (R-38), vaulted ceiling over entry and living room Walls - All exterior walls 2x6 studs @ 16" OC, 5 1/2" fiberglass insulation (R-19) Windows - All windows double glazed aluminum frame with thermal break (Letters refer to Figure 5.1) @ (2) 3'-0" x 5'-0" Vert. Sliding 6'-0" x 3'-0" Sliding © 2'-0" x 5'-0" Fixed @ (2) 2'-0" x 5'-0" Vert. Sliding © 3'-0" x 5'-0" Vert. Sliding © (2) 3'-0" x 3'-0" Fixed © 1'-0" x 3'-0" Vert. Sliding @® (2) 3'-0" x 4'-0" Vert. Sliding Doors - (Numbers refer to Figure 5.1) 3'-0" x 6'-8" - 1 3/4" Solid Core Wood 6'-0" x 6'-8" Slider (double glazed with aluminum frame and thermal break) 10'-0" x 7'-0" Overhead Wood Panel ©O © Floor - Main Level - 2x10" joists @ 16" OC, all exposed floors insulated to R-19 Lower Level - Concrete slab B.6 “‘q TABLE B.3. Heat Load Calculations for Filter Building Outdoor Design Temperature = -5°F Design Temperature Difference = 65°F Interior Design Temperature = 60°F Total Heat Load = 56,019 Btu/hr Larger Storage Smaller Storage Const Filter Room Room Room (a) Area or Area or Area or No. HTM Length —BtuH Length _BtuH = Length BtuH Gross Exposed 10a 176 Walls & 10d 352 192 144 Partitions Windows & 4a 90 48 4320 18 1620 9 810 Glass Doors Other Doors 9c 290 84 24360 21 6090 Net Exposed 10a 16 119 1904 Walls & 10d 5 279 1395 153 765 135 675 Partitions Ceilings 14b 5 484 2420 140 700 80 400 Floors 17b 15 484 7260 140 2100 80 1200 Subtotal BtuH Loss 41659 11275 3085 Duct BtuH Loss Total BtuH Loss 41659 11275 3085 (a) From ACCA Manual J. Table 2 (ACCA 1975, p. 31-33). Heat Loss and Heat Gain Calculation Worksheet format from (ACCA 1975, p. 13). TABLE B.4. Heat Load Calculation Data for Filter Building Ceiling - Wood trusses @ 16" OC, 3 1/2" fiberglass insulation, no interior sheathing in filter room, sheetrock in storage rooms Walls - 2x4 studs @ 16" OC, T-111 plywood exterior sheathing, 3.1/2" fiberglass insulation and sheathing on all walls except west wall of filter room, west wall of filter room is not insulated Windows - (Letters refer to Figure 5.2) () 3'-0" x 4'-0" Fixed Single Glass 3'-0" x 4'-0" Fixed Single Glass © 3'-0" x 4'-0" Fixed Single Glass @) 3'-0" x 3'-0" Bottom Opening Single Glass ® 3'-0" x 3'-0" Bottom Opening Single Glass ® 3'-0" x 3'-0" Bottom Opening Single Glass G 3'-0" x 4'-0" Fixed Single Glass Doors - (Numbers refer to Figure 5.2) @ 9'-0" x 7'-0" Overhead Metal Panel @ 3'-0" x 6'-8" Interior door (single 3/8" Plywood with 1 3/4" frame) @ 3'-0" x 6'-8" Interior door (single 3/8" plywood with 1 3/4" frame) Floor - 3/4" plywood floor on 2x6" joists @ 16" OC on blocks raised about 8" above ground B.8 6°9 TABLE B.5. Heat Load Calculations for Warehouse Outdoor Design Temperature = -50F Design Temperature Difference = 65°F Interior Design Temperature = 60°F Total Heat Load = 213,772 Btu/hr Garage Office Woodsho} Const. Wear Reo No. (4) HTM Length _BtuH Length += Btu _— Length ~—_—BtuH Gross Exposed 1 3738 Walls & 2 210 808 Partitions Windows & 2b 65 48 3120 144 9360 Glass Doors 4b 55 96 5280 Other Doors 9b 155 277 42935 21 3255 Net Exposed 1 6.5 346 22496 Walls & 2 5.0 162 810 547 2735 Partitions Ceilings 1 6.5 3540 23010 Floors 21a 125 178 22250 20 2500 77 9625 Subtotal BtuH Loss 110691 6430 30255 Duct BtuH Loss Total BtuH Loss 110691 6430 30255 (a) From ACCA Manual J. Table 2 (ACCA 1975, p. 31-33). Heat Loss and Heat Gain Calculation Worksheet format from (ACCA 1975, p. 13). ota TABLE B.5. (contd) Const Machine Sho Toilet Room Boiler Room (a) Area or Area or Area or No. HTM Length BtuH Length _ BtuH Length BtuH Gross Exposed 1 Walls & 2 693 95 105 Partitions Windows & 2b 65 168 10920 24 1560 Glass Doors Other Doors 9b 155 42 6510 Net Exposed 2 5.0 525 2625 71 355 63 315 Walls & Partitions Ceilings 1 Floors 21a 125 66 8250 9 1125 10 1250 Subtotal BtuH Loss 21795 3040 8075 Duct BtuH Loss Total BtuH Loss 21795 3040 8075 (a) From ACCA Manual J. Table 2 (ACCA 1975, p. 31-33). Heat Loss and Heat Gain Calculation Worksheet format from (ACCA 1975, p. 13). Il'@ TABLE B.5. (contd) Passage Open Front Storage Const. Area or rea or rea or No. (2) HTM Length BtuH Length BtuH Length_ BtuH Gross Exposed 1 399 684 Walls & 2 Partitions Windows & Glass Doors Other Doors Net Exposed 1 6.5 399 2593 684 4446 Walls & Partitions Ceilings 1 6.5 1140 7410 1287 8365 Floors Subtotal BtuH Loss 10003 12811 Duct BtuH Loss Total BtuH Loss 10003 12811 (a) From ACCA Manual J. Table 2 (ACCA 1975, p. 31- 33). Heat Loss and Heat Gain Calculation Worksheet format from (ACCA 1975, p. 13). era TABLE B.5. (contd) Rear Storage Hall Const. engp ot Area or No. (4) HTM Length Gross Exposed 1 Walls & 2 446 Partitions Windows & Glass Doors Other Doors Net Exposed 1 6.5 466 Walls & Partitions Ceilings 1 6.5 540 Floors Subtotal BtuH Loss Duct BtuH Loss Total BtuH Loss (a) From ACCA Manual J. Table 2 (ACCA 1975, p. Worksheet format from (ACCA 1975, p. 13). BtuH Length 3029 3510 152 6539 6539 31-33). Heat Loss BtuH 988 988 988 and Heat Diver Supp] Area or Length BtuH 161 161 1046 323 2099 3145 3145 Gain Calculation TABLE B.6. Heat Load Calculation Data for Warehouse Ceiling - Butler F-103 1" wall system, U = 0.1 Walls - Butler F-103 1" wall system U = 0.1, except for builtup wall with U = 0.07" office, woodshop, machine shop, toilet room, and boiler room Windows - (Letters refer to Figures 5.3 and 5.4) @ 4'-0" x 6'-0" Horizontal Sliding Aluminum Frame Double Glazed 4'-0" x 7'-0" Fixed Aluminum Frame Double Glazed Doors - (Numbers refer to Figures 5.3 and 5.4) @ 3'-0" x 7'-0" Foam Core Steel Exterior Doors @ 16'-0" x 16'-0" Overhead Plywood Door ® 3'-0" x 7'-0" Foam Core Steel Exterior Doors ® 6'-0" x 7'-0" Foam Core Steel Exterior Doors Floor - Concrete slab B.13 TABLE B.7. Summary of Design Heat Loads and Heating System for Snettisham Salmon Hatchery Outdoor Design Temperature = -20°F interior estan Tem Heat Heating System Components 0 P- Load ating Room _(F) (Btu/hr) kW) Type Shop 70 23,400 10 Unit Heater Office/Hall 70 20,860 5 Cabinet Unit Heater 2.5 Fin Pipe Heaters (2) Lab 70 6,200 1.5 Wall Heater Women 70 760 1.5 Wall Heater Men 70 1,700 L.5 Wall Heater Mech. #2 70 4,600 45 Booster Coil 4 Booster Coil 12 Heating Coil 6 Hot Water Heater Ventilation Heat Load (110 cfm) 11,433 Subtotal @ 70° 68,953 Incubation 45 106,700 Mech. #1 45 2,080 1.5 Wall Heater 1.5 Hot Water Heater Storage & 45 8,880 5 Unit Heater Egg Sorting 8 Infrared Heaters (2) Egg Handling 45 14,560 5 Unit Heater 8 Infrared Heaters (2) Formalin 45 2,940 Storage Generator Room 45 10 Unit Heater Ventilation Heat Load (315 cfm) 23,634 Subtotal @ 45° 158,794 TOTAL 227,747 128 Source: Discussions with Vern Akin, Mechanical Design Engineer, April 1980. B.14 APPENDIX C DETAILED HEATING SYSTEM DESIGN INFORMATION TO DOMESTIC SERVICE 1-1/2 GALV SUPPLY |& WATER ae PUMP Mi Os ! 21/2" BMG DK DISPOSAL WELL SYMBOLS NOTES: —DKL GATE VALVE —+ HOSE BIB Lc —S4— GLOBE VALVE —- Y STRAINER 1. bi onan ae ee ah SOLENOID VALVE —P) PRESSURE GAUGE AT PUMP —Q— BALL COCK —@ THERMOMETER WITHIN HEAT PUMP. —N— CHECK VALVE r{P) PRESSURE SWITCH —{] VACUUM switcH % FLOAT VALVE is RELIEF VALVE FIGURE C.1. Piping Design for Residence Pp S yy possssssssssssomks Sosoostecsscsseg PSSSSSSSSSSSSSSSSE MAIN LEVEL Rooosssossssy {SSS SSS SSS Sof LOWER LEVEL Ductwork Design for Residence 2 FIGURE C C.2 e°9 PRESSURE AND STORAGE TANK SEAWATER gl HEADER EXISTING Oo > SUMP PUMP) & WITH INTAKE STRAINER SUMP IN WET LAB SEA WATER EFFLUENT P1PE LABORATORY BUILDING FIGURE C.3. FILTER BUILDING 1-1/4" PVC 1-1/4" PVC NOTES: 1, WATER FLOW CONTROL VALVES ARE ASSUMED TO BE LOCATED WITHIN THE HEAT PUMP. | | | I | | Heat | ! | | pump |! | | ! | | | ee Mee SYMBOLS —DKE- GATE VALVE —+ — HOSE BIB —{S4— GLOBE VALVE OE Y STRAINER = SOLENOID VALVE —{P) PRESSURE GAUGE —Q— BALL COCK THERMOMETER IN CHECK VALVE —{¥] VACUUM swiTCH i RELIEF VALVE Piping Design for Filter Building = ce Fs PRESSURE SWITCH FLOAT VALVE FIGURE C.4. Ductwork Design for Filter Building C.4 $°9 FIRST FLOOR —— 2 FIGURE C.5. Ductwork design for First Floor of Warehouse — FIGURE C.6. Ductwork Design for Mezzanine of Warehouse 9°9 VENT ~ ® BOOSTER CHLOR INATOR HEAT HEAT ey PUMP PUMP PUMP UNIT UNIT rh P) [P HA 18 CHLORINE OL® MOHD oO a SUPPLY PRESSURE K K ©) WELL z 2 TANK | © CASING 7 2 = x | BASKET STRAINER x ve = 1-114" PVC t ? i LN 2" PVC 2" PVC 1-1/4" PVC >" pyc I-A" PVC] ove 1" Pvc | SYMBOLS SEA LEVEL v —DKLE GATE VALVE —+ HOSE BIB shy — GLOBE VALVE a Y STRAINER he SOLENOID VALVE a PRESSURE GAUGE NOTES: —Q— BALL COCK -O THERMOMETER SUBMERSIBLE PUMP FIGURE C.7. —NE— CHECK VALVE 1, WATER FLOW CONTROL VALVES ARE | —{4) vacuum switce ASSUMED TO BE LOCATED WITHIN a RELIEF VALVE THE HEAT PUMPS PRESSURE SWITCH FLOAT VALVE Piping Design for Warehouse FROM INCUBATION ROOM HEADBOX T i 1 1 | HYDRO | HEAT ! \PNEUMATIC | PUMP puMP 1 TANK | UNIT IIA 1 I-74 85, 000 ! pee ' TO DOMESTIC = hbk ane SERVICE DOMESTIC 4 . WATER PUMP 2" Cy» | CHLORINATOR I'Cu oO yy é HEAT UNIT I1B 85, 000 SYMBOLS —DKE-— GATE VALVE —{S4— GLOBE VALVE 2% sounoro vaive TO FLOOR DRAIN —Q— BALL COCK —INi— CHECK VALVE VACUUM SWITCH is RELIEF VALVE FIGURE C.8. Piping Design for Salmon Hatchery a HOSE BIB —}- Y STRAINER +?) = Fs PRESSURE GAUGE THERMOMETER PRESSURE SWITCH FLOAT VALVE 110 CFM EXHAUST TO OUTSIDE HEAT PUMP 6 SUPPLY REGISTERS @ 27.5 ft SPACING ON NORTH AND SOUTH SIDES OF INCUBATION ROOM (12 TOTAL) Sad EAST END FIGURE C.9. Ductwork Design for East End of Salmon Hatchery © 315 CFM ® EXHAUST TO OUTSIDE >) WEST END FIGURE _C.10. Ductwork Design for West End of Salmon Hatchery C.8 APPENDIX D LIFE CYCLE COST CALCULATIONS TABLE D.1. Annual Heating Requirements for Residence - Case 1 Temperature gyrgy «CR __(°F) Year (Btu/hr) (1000 Btus) 62 56 1,837 103 57 100 4,900 490 52 292 7,962 2,325 47 649 11,025 7,155 42 1,192 14,087 16,792 37 1,207 17,150 20,700 32 1,169 20,212 23,628 27 1,446 23,275 33,656 22 1,117 26 , 336 29,419 17 545 29,400 16,023 12 328 32,462 10,648 200 35,525 7,105 163 38,587 6,290 -3 119 41,650 4,956 -8 60 44,712 2,683 -13 29 47,775 1,385 -18 _ i 50,837 559 Total 8,683 -- 183,917 Source: See note, page D.6. D.1 TABLE D.2. Annual Heating Requirements for the Filter Building - Case 2 Outdoor Temperature Hours/ teas gees __(°F) Year (Btu/hr) (1000 Btus) 62 292 0 0 57 649 0 0 52 1,192 2,850 3,397 47 1,207 7,600 9,173 42 1,169 12,350 14,437 37 1,446 17,100 24,726 32 1,117 21,850 24,406 27 545 26 600 14,497 22 328 31,350 10,282 17 200 36,100 7,220 12 163 40,850 6,658 7 119 45 600 5,426 2 60 50,350 3,021 -3 29 55,100 1,598 -8 9 59,850 538 -13 2 64,600 129 -18 __0 0 0 Total 8,527 -- 125,508 Source: See note, page D.6. D.2 TABLE D.3. Annual Heating Requirements for the Warehouse - Case 3 Tesearatare ||| Feawsy ||) seit) ||| gutles er) Year (Btu/hr) (1000 Btus) 62 292 0 0 57 649 0 0 52 1,192 10,700 12,754 47 1,207 28,533 34,439 42 1,169 46 , 366 54,202 37 1,446 64,200 92,833 32 1,117 82,033 91,631 27 545 99,866 54,427 22 328 117,700 38,605 17 200 135,533 27,106 12 163 153, 366 24,998 119 171,200 20,372 2 60 189,033 11,342 -3 29 206 , 866 6,000 -8 9 224,700 2,022 -13 2 242,533 485 -18 LS 0 0 Total 8,527 -- 471,216 Source: See note, page D.6. 0.3 TABLE D.4. Annual Heating Requirements for Snettisham Fish Hatchery - Case 4 (Portion of building with interior design temperature of 70°F) Outdoor Temperature yours ‘HERG __(°F) Year (Btu/hr) (1000 Btus) 62 30 2,435 73 57 56 6,494 363 52 100 10,552 1,055 47 292 14,611 4,266 42 649 18,670 12,116 37 1,192 22,729 27,092 32 1,207 26,788 32,333 27 1,169 30,847 36 ,060 22 1,446 34,905 50,472 7 1,117 38,964 43,522 12 545 43,023 23,447 328 47 ,082 15,442 2 200 51,141 10,228 -3 163 55,200 8,997 -8 119 59,258 7,051 -13 60 63,317 3,799 -18 29 67,376 1,953 -23 9 71,435 642 -28 _ 2 75,494 150 Total 8,713 7 279,061 Source: See note, page D.6. D.4 TABLE D.5. Annual Heating Requirements for Snettisham Fish Hatchery - Case 4 (Portion of building with interior design temperature of 45°F) Temberstire— jourgy ‘RE _teat ng __(°F) Year (Btu/hr) (1000 Btus) 62 30 0 0 57 56 0 0 52 100 0 0 47 292 0 0 42 649 7,338 4,762 37 1,192 19,569 23,326 32 1,207 31,800 38,382 27 1,169 44,030 51,471 22 1,446 56,261 81,354 17 1,117 68,492 76,505 12 545 80,723 43,994 7 328 92,953 30,488 2 200 105,184 21,036 -3 163 117,415 19,138 -8 119 129,646 15,427 -13 60 141,876 8,512 -18 29 154,107 4,469 -23 9 166 ,338 1,497 -28 _ 2 178,569 357 Total 8,713 7 420,718 Source: See note, page D.6. D.5 NOTES FOR TABLES D.1 THROUGH D.5 The shape of the annual temperature distribution used in the annual heat- ing requirement calculations presented in Tables D.1 through D.5 is from The Role of Electric Power in the Southeast Alaska Energy Economy, prepared by Applied Economics Associates, Inc. for the Alaska Power Administration, March 1979. The temperature data in that report is from Air Force Manual 88-8 and are averages for the Juneau airport over a 10-year period. The design load outdoor temperature for the Juneau airport is -5°F, In the case of the Mendenhall Valley residence a -15°F design tempera- ture was suggested to be more representative of the local conditions by Juneau area heating contractors. The entire annual temperature distribution was reduced by 10°F for the Mendenhall Valley area. This temperature distribu- tion is the same as is used in A Comparison of Home Heating Costs: Electricity Versus O0i1, prepared by CH2M Hill for the Glacier Highway Electric Association, Auke Bay, Alaska, February 1980. The Auke Bay area (the location of the filter building) was assumed to have a design load temperature and temperature distribution similar to the Juneau airport. The warehouse located at the NMFS subport facilities on the Juneau waterfront was also assumed to have a design load temperature and a temperature distribution similar to the Juneau airport. A -20°F design load outdoor temperature was used for the design of the Snettisham salmon hatchery which is presently under construction. Since the temperature distribution for the Snettisham area was not available it was assumed that the shape of the temperature distribution at Snettisham was similar to the distribution at the Juneau airport. The entire temperature distribution was reduced by 15°F. D.6 TABLE D.6. Life Cycle Cost Calculation for Direct Baseboard Electrical Resistance Heating for Residence in the Mendenhall] Valley Total Annual Annual Total Electricity Electricity Electrical O&M Investment Annual Required Cost Cost Cost Cost Cost (kwh) 2) ($key) ($) (sy) (gy (4) ($) 1981 53875 0.0374 2014 -- 327 2341 1982 53875 0.0389 2095 -- 327 2422 1983 53875 0.0405 2181 -- 327 2508 1984 53875 0.0421 2268 -- 327 2595 1985 53875 0.0438 2359 -- 327 2686 1986 53875 0.0550 2963 -- 327 3290 1987 53875 0.0571 3076 -- 327 3403 1988 53875 0.0594 3200 -- 327 3527 1989 53875 0.0618 3329 -- 327 3656 1990 53875 0.0643 3464 198 327 3989 Present Worth (@ 8%) = $19,606 Levelized Cost (10 years @ 8%) = $2921 (a) Electrical resistance heating assumed to be 100% efficient. {2} See Figure 1.2. c) Based on $46/hr wage rate (1980 price level). (d) See Table 6.6. D.7 TABLE D.7. Life Cycle Cost Calculation for Fluid Filled Baseboard Electrical Resistance Heating for Residence in the Mendenhall Valley Total Annual Annual Total Electricity Electricity Electrical O&M Investment Annual Required Cost Cost Cost Cost Cost cay ($/kWh) (>) ($) (sy) (gy (4) ($) 1981 53875 0.0374 2014 -- 405 2419 1982 53875 0.0389 2095 -- 405 2500 1983 53875 0.0405 2181 -- 405 2586 1984 53875 0.0421 2268 -- 405 2673 1985 53875 0.0438 2359 -- 405 2764 1986 53875 0.0550 2963 -- 405 3368 1987 53875 0.0571 3076 -- 405 3481 1988 53875 0.0594 3200 -- 405 3605 1989 53875 0.0618 3329 -- 405 3734 1990 53875 0.0643 3464 198 405 4067 Present Worth (@ 8%) = $20,129 Levelized Cost (10 years @ 8%) = $2999 (a) Electrical resistance heating assumed to be 100% efficient. (b) See Figure 1.2. (c) Based on $46/hr wage rate (1980 price level). (d) See Table 6.6. 0.8 TABLE D.8. Life Cycle Cost Calculation for Oil-Hydronic Heating for Residence in the Mendenhall Valley Total Annual Annual Total Fuel Oi] Fuel Oi] Fuel Oi] O&M Investment Annual Required Cost Cost Cost Cost Cost (Gallons) ‘@) ($/gal1on) ‘) ($) ($) 6°) ($) (4) ($) 1981 2412 1.03 2484 75 475 3034 1982 2412 1.15 2774 81 475 3330 1983 2412 1.27 3063 87 475 3625 1984 2412 1.41 3401 94 475 3970 1985 2412 1.57 3787 204 475 4466 1986 2412 1.74 4187 109 475 4771 1987 2412 1.93 4655 118 475 5248 1988 2412 2.14 5162 127 475 5764 1989 2412 2.38 5741 138 475 6354 1990 2412 2.64 6368 297 475 7140 Present Worth (@ 8%) = $30,164 Levelized Cost (10 years @ 8%) = $4495 (a) Oil-hydronic home heating assumed to be 55% efficient. Fuel oi] heating value assumed to be 138,690 Btu/gallon. (b) See Figure 1.1. (c) Based on $46/hr wage rate (1980 price level). (d) See Table 6.6. D.9 TABLE D.9. Life Cycle Cost Calculation for Air to Air Heat Pump for Residence in the Mendenhall Valley Total Annual Annual Total Electricity Electricity Electrical O&M Investment Annual Required Cost Cost Cost Cost Cost (kwh) (2) ($/kwh) () ($) (3) (©) ($) (4) ($) 1981 28114 0.0374 1051 -- 882 1933 1982 28114 0.0389 1093 108 882 2083 1983 28114 0.0405 1138 -- 882 2020 1984 28114 0.0421 1183 -- 882 2065 1985 28114 0.0438 1231 272 882 2385 1986 28114 0.0550 1546 -- 882 2428 1987 28114 0.0571 1605 158 882 2645 1988 28114 0.0594 1669 -- 882 2551 1989 28114 0.0618 1737 -- 882 2619 1990 28114 0.0643 1807 396 882 2689 Present Worth (@ 8%) = $15,323 Levelized Cost (10 years @ 8%) = $2283 (a) Annual electricity required is derived from case fdr air to air heat pump heating in CH2M (1980), Appendix Table 6. Annual’electricity required is assumed to be proportional to total heating requirement. 240,223 KBtu [heating required from CH2M (1980)] > tu (heating calculated for residence - 6,722 kWh [annual energy consumption from CH2M (1980 28,114 kWh (derived annual energy consumption for residence This is equivalent to a seasonal system COP of 1.92 which is the same as CH2M (1980), Appendix Table 6. (b) See Figure 1.2. (c) Based on $46/hr wage rate (1980 price level). (d) See Table 6.6. D.10 TABLE D.10. Life Cycle Cost Calculation for Water Source Heat Pump Heating for Residence in the Mendenhall Valley Total Annual Annual Total Electricity Electricity Electrical O&M Investment Annual Required Cost Cost Cost Cost Cost 1981 23949 0.0374 895 -- 1864 2759 1982 23949 0.0389 931 108 1864 2903 1983 23949 0.0405 969 -- 1864 2833 1984 23949 0.0421 1008 -- 1864 2872 1985 23949 0.0438 1048 272 1864 3184 1986 23949 0.0550 1317 -- 1864 3181 1987 23949 0.0571 1367 158 1864 3389 1988 23949 0.0594 1422 -- 1864 3286 1989 23949 0.0618 1480 -- 1864 3344 1990 23949 0.0643 1539 396 1864 3799 Present Worth (@ 8%) = $20,751 Levelized Cost (10 years @ 8%) = $3092 (a) Seasonal system COPs for WSHPs vary depending upon the design of spe- cific units and the blower and pumping allowance included. A seasonal system COP of 2.25 is used in this cost comparison. This includes both blower and pump allowances. The pump allowance is based upon 160 ft total head and a 30% wire-to-water efficiency. {b} See Figure 1.2. c) Based on $46/hr wage rate (1980 price level). (d) See Table 6.5. 0.11 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 TABLE D.11. Life Cycle Cost Calculation for Forced Air Oi] Heating for Filter Building Total Annual Annual Fuel 071 Fuel 071 Fuel Oil O&M Investment Required Cost Cost Cost Cost (Gallons) ‘?) ($/galton) ') ($) (sy!) ($) (4) 1645 1.03 1694 75 428 1645 1.15 1891 81 428 1645 1.27 2089 87 428 1645 1.41 2319 94 428 1645 1.57 2582 204 428 1645 1.74 2862 109 428 1645 1.93 3174 118 428 1645 2.14 3520 127 428 1645 2538 3915 138 428 1645 2.64 4342 297 428 Present Worth (@ 8%) = $21,532 Levelized Cost (10 years @ 8%) = $3208 Total Annual Cost (S$) 2197 2400 2604 2841 3214 3399 3720 4075 4481 5067 (a) Computed fuel oi] requirements assuming a 55% heating efficiency and 138,690 Btu/gallon is 1645 gallons/year. (b) (c) Based on $46/hr wage rate (1980 price level). (d) 3-year average of 1548 gallons/year. between the alternatives the computed value is used in Table D.5. See Figure 1.1. See Table 6.8. 0.12 Actual consumption for year 1977 was 1258 gallons, for 1978 was 1344 gallons, and for 1979 was 2044 gallons (data supplied by NMFS, March 17, 1980). This gives a In order to maintain consistency 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 Pres Leve (a) (b) (c) (d) TABLE D.12. Life Cycle Cost Calculation for Water Source Heat Pump Heating for Filter Building Total Annual Annual Total Electricity Electricity Electrical O&M Investment Annual Required Cost Cost Cost Cost Cost _(kiuh) (2) ($/kwh) () ($) ($) 6°) ($y (4) ($) 15195 0.0489 743 -- 2240 2983 15195 0.0508 771 108 2240 3119 15195 0.0529 803 -- 2240 3043 15195 0.0550 835 -- 2240 3075 15195 0.0572 869 272 2240 3381 15195 0.0690 1048 -- 2240 3288 15195 0.0717 1089 158 2240 3487 15195 0.0746 1133 -- 2240 3373 15195 0.0776 1179 -- 2240 3419 15195 0.0807 1226 396 2240 3862 ent Worth (@ 8%) = $21,838 lized Cost (10 years @ 8%) = $3254 Seasonal system COPs for WSHPs vary depending upon the design of spe- cific units and the blower and pumping allowances included. A seasonal system COP of 2.40 is used here. This includes both blower and pump allowances. The pump allowance is based upon 140 ft total head and a 30% wire-to-water efficiency. See Figure 1.2. Based on $46/hr wage rate (1980 price level). See Table 6.8. 0.13 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 Pres Leve (a) (b) ta TABLE D.13. Life Cycle Cost Calculation for 0il-Hydronic Heating for Warehouse Total Annual Annual Total Fuel 071 Fuel Oi] Fuel Oil 0&M Investment Annual Required Cost Cost Cost Cost Cost (Gallons) (4) ($/gal ton) (>) ($) ($) 6°) (gy (4) ($) 4853 0.97 4707 150 3565 8422 4853 1.07 5192 162 3565 8919 4853 1.19 5775 174 3565 9514 4853 1.32 6405 189 3565 10159 4853 1.47 7133 408 3565 11106 4853 1.63 7910 219 3565 11694 4853 1.81 8783 237 3565 12585 4853 2.00 9706 255 3565 13526 4853 2.23 10822 276 3565 14663 4853 2.47 11986 594 3565 16145 ent Worth (@ 8%) = $74,853 lized Cost (10 years @ 8%) = $11,155 Computed fuel oil requirements assuming a 70% heating efficiency and 138,690 Btu/gallon is 4853 gallons. Actual consumption for year 1975 was 2978 gallons, for 1976 was 3786 gallons, for 1977 was 3291, for 1978 was 3681, and for 1979 was 5023 gallons (data supplied by NMFS, April 17, 1980). This gives a 5-year average of 3751 gallons/year. The difference between actual and computed oil consumption could be attributed to a num- ber of factors such as the building being better insulated than assumed, design conditions being less severe than assumed, heating efficiency of furnace higher than assumed, more natural heat gain than assumed (none was assumed), etc. In order to maintain air consistency between the alternatives the computed value is used in Table D.7. 1980 price for fuel oil in 1500 gallon quantities was about $0.87 (NMFS data, April 17, 1980). The price is assumed to escalate at 11% year. Based on $46/hr wage rate (1980 price levels). See Table 6.11. D.14 TABLE D.14. Life Cycle Cost Calculation for Water Source Heat Pump Heating for the Warehouse 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 Electricity Required (kwh)'?) —($ykwhy () ($) (sy) gy (4) 60028 60028 60028 60028 60028 60028 60028 60028 * 60028 60028 Electricity Cost 0.0374 0.0389 0.0405 0.0421 0.0438 0.0550 0.0571 0.0594 0.0618 0.0643 Present Worth (@ 8%) = $92,260 Levelized Cost (10 years @ 8%) = $13,749 Total Electrical Cost 2245 2335 2431 2527 2629 3301 3427 3565 3709 3859 Annual 0&M Cost 415 759 455 480 1321 530 1034 590 625 1848 Annual Investment Cost 10117 10117 10117 10117 10117 10117 10117 10117 10117 10117 Total Annual Cost (S$) 12777 13211 13003 13124 14067 13948 14578 14272 14451 15824 (a) Seasonal system COPs for WSHPs vary depending upon the design of spe- cific units and the blower and pumping allowances included. system COP of 2.3 is used in this case. pump allowances. a 30% wire-to-water efficiency. (b) See Figure 1.2. (c) Based on $46/hr wage rate (1980 price level). A seasonal This includes both blower and The pump allowance is based upon 180 ft total head and for sodium hypochlorite. (d) See Table 6.11. 0.15 Also includes $165/year TABLE D.15. Life Cycle Cost Calculation for Electrical Resistance Heating for Snettisham Salmon Hatchery Total Annual Annual Total Electricity Electricity Electrical O&M Investment Annual Required Cost Cost Cost Cost Cost (kwh) (2) ($/kWh) (>) ($) ($) (©) ($) (4) ($) 1981 205033 0.0160 3280 -- 5526 8806 1982 205033 0.0160 3280 -- 5526 8806 1983 205033 0.0160 3280 -- 5526 8806 1984 205033 0.0160 3280 -- 5526 8806 1985 205033 0.0160 3280 272 5526 9078 1986 205033 0.0254 5207 -- 5526 10733 1987 205033 0.0254 5207 -- 5526 10733 1988 205033 0.0254 5207 -- 5526 10733 1989 205033 0.0254 5207 -- 5526" 10733 1990 205033 0.0254 5207 396 5526 11129 Present Worth (@ 8%) = $64,688 Levelized Cost (10 years @ 8%) = $9640 (a) Electrical resistance heating assumed to be 100% efficient. (b) Electricity cost through 1985 set at $0.016/kWh. Electricity cost for 1986-1990 assumed to be $0.0004 above wholesale rate. (c) Based on $46/hr wage rate (1980 price levels). (d) See Table 6.14. D.16 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 TABLE D.16. Electricity Required 82013 82013 82013 82013 82013 82013 82013 82013 82013 82013 Total Electricity Electrical Cost Cost (kwh) '?) —(§kwny 6) ($) 0.0160 1312 0.0160 1312 0.0160 1312 0.0160 1312 0.0160 1312 0.0254 2083 0.0254 2083 0.0254 2083 0.0254 2083 0.0254 2083 Life Cycle Cost Calculation for Water Source Heat Pump Heating for Snettisham Salmon Hatchery Present Worth (@ 8%) = $70,563 Levelized Cost (10 years @ 8%) = $10,516 (a) Seasonal system COPs for WSHPs vary depending upon the design of specific units and the blower and pumping allowances included. seasonal system COP of 2.5 is used in this case. blower and pump allowances. total head and a 30% wire to water efficiency. Annual O&M Cost ($) (¢) ($) (4) (b) Electricity cost through 1985 set at $0.016/kWh. (c) Based on $46/hr wage rate (1980 price levels). (d) See Table 6.14. D.17 Annual Investment Cost 8645 8645 8645 8645 8645 8645 8645 8645 8645 8645 Total Annual Cost 9957 10281 9957 9957 10773 10728 11202 10728 10728 11916 This includes both The pump allowance is based upon 140 ft. Electricity cost for 1986-1990 assumed to be $0.0004 above wholesale rate.