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HomeMy WebLinkAboutTelida Reconnaissance Study of Energy Requirements & Alternatives 1981OF ENERGY REQUIREMENTS & ALTERNATIVES FOR TELIDA INTERNATIONAL ENGINEERING COMPANY, INC. A MORRISON-KNUDSEN COMPANY ROBERT W. RETHERFORD ASSOCIATES DIVISION TELIDA SUPPLEMENT TO RECONNAISSANCE STUDY OF ENERGY REQUIREMENTS AND ALTERNATIVES FOR BUCKLAND, CHUATHBALUK, CROOKED CREEK HUGHES, KOYUKUK, NIKOLAI, RED DEVIL, RUSSIAN MISSION, SHELDON POINT, SLEETMUTE, STONY RIVER, TAKOTNA AND TELIDA MAY 1981 Prepared by: Robert W. Retherford Associates Arctic Division of International Engineering Co., Inc. Anchorage, Alaska For the State of Alaska Department of Commerce and Economic Development Division of Alaska Power Authority 333 West Fourth Avenue, Suite 31 Anchorage, Alaska 99501 Under Contract No. AS44.56.010 APA 20/T1 A “20 This report was prepared by: Robert W. Retherford Associates Arctic Division of International Engineering Company R.W. Retherford, P.E. Frank J. Bettine, E.1.T. James J. Lard, E.1.T. Mark Latour, Economist Illustrations on the front cover were prepared and sketched by Kathryn L. Langman. These illustrations portray several energy resource alternatives investigated for the Thirteen Villages included in this study. APA 20/T2 Section No fF wWwhr APPENDIX A APA*32C1 TABLE OF CONTENTS Summary and Results Recommendations Existing Conditions and Energy Balance Energy Requirements Forecast Resource and Technology Assessment Energy Plans Description of Selected Technologies 1.2 2.1 3.1 4.1 5.1 6.1 SECTION 1 SUMMARY AND RESULTS APA*32C2 SECTION 1 SUMMARY AND RESULTS A. SUMMARY A study was recently conducted under contract number AS44.56.010 for the State of Alaska Department of Commerce and Economic Development, Divi- sion of Alaska Power Authority to determine the energy alternatives for Thirteen Western Alaskan Villages. This study consists of establishing the following: Energy Balance for 1979 Existing Power and Heating Facilities - 1980 Electric Power Requirements to the year 2000 Space Heating Requirement to the year 2000 Potential Energy and Electric Power Resources Evaluation of the Electric Power Resources Recommendations for the development or future studies for the 13 Western Alaskan villages of Buckland, Hughes, Koyukuk, Telida, Nikolai, Takotna, Stony River, Sleetmute, Red Devil, Crooked Creek, Chuathbaluk, Russian Mission and Sheldon Point (See Figure 1.1). The Telida supplement represents a brief summary of the most pertinent facts and findings contained in the original report which relate to the village of Telida. Detailed data concerning the village may be obtained by referring to the original report. Diesel fuels are presently used to satisfy the major percentage of energy demands in the village. Emphasis in the study was therefore placed on possible resources and technologies that could replace or at least supple- ment the use of increasingly costly fuel oi]. The energy alternatives which were selected for detailed evaluation in the village of Telida include: 1! 1) Diesel generation 2) Waste Heat Recovery 3) Binary Cycle generation using wood fuel 4) Wind generation 5) Passive solar heating 6) Energy conservation 1 See Appendix A for brief description of technologies listed. 1-1 APA*32H1 BARROW CCkay, Nootok River BUCKLAND HUGHES KOYUKUK RUSSIAN MISSION @eSnounnwn — ee SHELDON POINT sl CHUATHBALUK Metsia nf CROOKED CREEK unia! * NIKOLAI 9 RED DEVIL Yukon ~ Tanana Plateau 10 SLEETMUTE oe 11 STONY RIVER 12 TAKOTNA \ 13 TELIDA 'Sus/ina R. | € liver vou oe | Mange, pte Ming ¥ ANCHORAGE \ at 9 ( So Ja of YAKUTAT q ~ = UNEA\ Guit of Alaska a \o Y, & g e Bristos BAY KODIAK pACIFIC OCEAN ik reed ge VAN pre (0 8 ; apt . ce Gs FIGURE 1.1 at ALASKA MAP 13 WESTERN VILLAGES SECTION 1 SUMMARY AND RESULTS To obtain a comprehensive understanding of future energy requirements for the village, a control year - 1979 - was established from which all projections have been made. Information related to village history, population and economic conditions, plus information regarding village government, transportation, power and heating facilities, fuel require- ments, etc., was collected to provide the necessary background data to support these projections. B. EVALUATION RESULTS 1. Economics Table 1.1 is a summary of the 20-year economic evaluation performed for the combination of alternatives (i.e., energy plans) selected for detailed study for Telida. This Table lists the accumulated present worth of plan costs and the accumulated present worth of the net benefits derived from non-electrical outputs, where: 1) Plan costs represent the cost for providing electrical generation, and 2) Net benefits represent the savings derived from waste heat capture or surplus hydroelectric energy used for electric heating. a. Twenty Year Evaluation Results Results of the 20-year economic evaluation indicate that the use of diesel with waste heat recovery to be most economical energy plan examined for Telida. The diesel generation supplemented with wind generation, and waste heat energy plan averaged approximately 15 percent greater cost than the diesel generation plus waste heat recovery plan for Telida. 1-3 APA*32H3 pol TELIDA Table 1.1 Accumulated Present Worth of Plan Costs and Benefits ($1,000) Diesel Diesel & & Diesel Binary Cycle Diesel WECS PERIOD & & & & Waste Heat Waste Heat Hydroelectric Waste Heat Cost-Benefit Cost-Benefit Cost-Benefit Cost-Benefit 20-year 964-73.9 1444-56.9 N/A “ 1111-50.8 SECTION 1 SUMMARY AND RESULTS The diesel generation plus binary cycle with waste heat recovery is found to be the most expensive method of providing electrical energy for Telida. Passive solar and energy conservation have not been economically evaluated in detail and they are, therefore, not listed in Table 1.1. Numerous past studies have shown the value of conservation and passive solar heating. An approximate fifteen percent reduction in fossil fuel requirements due to the implementation of passive solar heating and energy conservation measures has been built into the village Heating Requirement Forecast Tables listed in Section 4. It is assumed that these two methods of reducing usage will be implemented in the village. 2 Environmental and Technical Results of the environmental and technical evaluations are listed in Table 1.2. These results indicate the overall environmental and technical ranking of energy plans selected for detail study for the village of Telida, in order of preference to be: 1) diesel electric plus waste heat 2) diesel plus waste heat and supplemented with wind generation 3) diesel plus binary cycle generation with waste heat APA*32H5 9-1 APA 2801 Table 1.2 Factor (A) Economic (Present Worth) (B) Environmental (1) Community Preference (2) Infrastructure (3) Timing (4) Air Quality (5) Water Quality (6) Fish and Wildlife (7) Land Use (8) Terrestrial Impacts TOTAL Environmental Ranking (C) Technical (1) Safety (2) Reliability (3) Availability TOTAL TECHNICAL RANKING OVERALL RANKING EVALUATION MATRIX Diesel + Diesel Local Hydro Electric w/wo Electric + Waste Heat Heat Inne wen ee w w ' Nm o ole won ran ' B-1 - Diesel + Binary Generation Coal and/or Wood With Waste Heat |p eR ee Oo w ~N lo nm 12 D-3 Diesel + Waste Heat Supplemental Wind Generation lw ww ww wow nN an leo thw 11 C-2 SECTION 2 RECOMMENDATIONS APA*32H6 SECTION 2 RECOMMENDATIONS A. GENERAL Analysis of the 20-year economic, technical and environmental evalu- ations indicate the three most promising energy plans for the village of Telida in order of preference to be: 1) Continued use of diesel generation supplemented with waste heat recovery, 2) diesel plus binary cycle generation supplemented with waste heat recovery, 3) diesel plus waste heat recovery supplemented with wind generation. B. RECOMMENDED PLAN - Diesel Generation Supplemented with Waste Heat Recovery. The 20-year economic, technical and environmental evaluation indicate that diesel generation with waste heat recovery will provide the most satisfactory method of providing electric energy for the village of Telida. It is recommended, therefore, that a study be conducted to determine the feasibility of utilizing waste heat in the village of Telida. Such a study should include a definitive review of the following items: 1) availability of waste heat 2) transportation of waste heat 3) end use of waste heat C. FIRST ALTERNATIVE PLAN - Diesel Plus Binary Cycle Generation Supple- mented With Waste Heat Recovery. The first alternative plan, as listed above, is diesel plus binary cycle generation with waste heat recovery. Because the uncertainties in the costs associated with this alternative, such as the cost of wood fuel, equipment cost, etc., which can not at present be as precisely determined as for the Cm APA*32H7 SECTION 2 RECOMMENDATIONS recommended plan, it is conceivable that this alternative could be cost competitive with the alternative plan (i.e., diesel generation plus waste heat recovery). Because binary cycle generation is viewed as one of the few potentially viable energy alternatives, suitable for future use in remote Alaska villages such as Telida, it is recommended that the feasibility of binary cycle generation in Alaska be further investigated in regard to: 1) Equipment availability 2) Technical feasibility 3) Economic aspects 4) Environmental aspects 5) Constraints Binary cycle generation equipment in unit sizes suitable for village appli- cation is, however, not expected to be available until the late 1980's. D. SECOND ALTERNATIVE PLAN - Diesel plus waste heat recovery supplement with wind generation. Alternative energy plan #2 diesel plus waste heat supplemented with wind generation is less expensive than alternative plan #1, but averages about 15 percent greater in costs than the recommended plan. Because of the marginal reliability heretofore experienced in Alaska using wind generation, implementation of this alternative is not recommended. However, as wind generation technology is further improved and developed, periodic reviews of wind technology for possible implementation in the village of Telida. E. COSTS FOR FURTHER STUDY Approximate costs for determining of feasibility of the two most attractive energy resources for the village of Buckland are: e Waste heat recovery - approximately $2500 2-2 APA*32H8 SECTION 2 RECOMMENDATIONS e Binary cycle generation. - approximately $2,000,000 which would include the cost of constructing and operating a demonstration plant in Alaska. F. CONSERVATION MEASURES For the village to stabilize and hopefully reduce the local cost of energy immediate short term conservation measures could provide the most rapid results. These conservation measures, which include added insulation, double glazing or solar film, arctic entrances, weather stripping, etc., can reduce current non-transportation fuel use on the order of 15 percent over the 20-year period of this study. 223 APA*32H9 SECTION 3 EXISTING CONDITIONS AND ENERGY BALANCE APA*32H10 SECTION 3 EXISTING CONDITIONS AND ENERGY BALANCE A. INTRODUCTION To establish a base and understanding of energy use in the village, an energy balance has been compiled for the year 1979. Input energy forms are diesel, wood, propane, blazo, gasoline, and aviation gasoline. Energy used in the village has been listed both by end use category (i.e., heating, transportation, and quantities used for electrical generation) and by consumer category to include residential, small commercial, public buildings, and large users (school), in the following table (Table numbered as in original report). To provide background data, information related to village history, demographic and economic conditions plus information regarding village government, transportation, power and heating facilities is included. a. GENERAL BACKGROUND INFORMATION History: Telida is located on the bank of the Swift Fork of the Kuskokwim River, 50 miles northeast of Medfra. The village was established at its persent site about 1916. Telida lies within the boundaries of Doyon Limited Corporation Population: L.T. J.S Herron, USA, visited Telida in 1899 and gave its population at 17 persons. In 1960 the village consisted of three families. The 1979 estimates place the population around 30. The 1980 estimates obtained during the visit to the village placed the population at 34 residents and seven families. The average number of members per household in the community is 4.4 persons. 3-1 APA*32H11 APA*32H12 SECTION 3 EXISTING CONDITIONS AND ENERGY BALANCE Economy: Telida's economy is heavily dependent on sub- sistence activities. Cash income in the community is from public assistance and from the sale of furs caught during the trapping season. Most residents fish and hunt waterfowl, rabbit, game birds and moose. In the fall, families harvest several varieties of berries. Transportation: Telida is not served by river barge. All passenger and supplies coming to the village are delivered primarily by aircraft. A gravel airstrip is located adjacent to the village. Small boats provide a means of transportation with neighboring villages during the summer months. Snowmachines provide the primary means of transportation in the winter. There are no roads which connect Telida with surrounding villages in the region. ENERGY BALANCE (1979) All residential heating in Telida is accomplished with 56.9 percent of the energy consumed. Electric generation uses 28.3 percent, and transportation uses approximately 14.8 percent. Graph 3.13 illustrates by consumer category the types and percentages of energy forms used in the village. Table 3.13 tabularizes this data in additional detail. EXISTING POWER AND HEATING FACILITIES Electric Power: There is no centralized power system in Telida. The school maintains and operates two 12-kW diesel generation units to provide electrical energy to the school. Three individuals in the community have a 3-2 APA*32H13 SECTION 3 EXISTING CONDITIONS AND ENERGY BALANCE 12-volt battery system installed in their residences. Batteries are charged from the school generators. The school also provides power to the satellite earth station. Heating: Residential heating is accomplished entirely with firewood. Telida residents average approximate 9 cords per year per household. Because of the high cost of heating with fuel oi] in Telida, the school district recently removed the fuel oi] furnace from the school and replaced it with a wood-burning stove. Heating of the school is now accomplished solely with wood. Fuel Storage: Diesel, bulk fuel oil storage in the community is estimated at 5,000 gallons (estimated during village visit). GRAPH 3.13 EFFICIENCIES ASSUMED: HEATING — 75% TRANSPORTATION — 25% ELECTRICAL GENERATION — 25% TOTAL ENERGY (100%) +t “ 0% HEATING (56.9%) TRANSPORTATION (14.8%) ELECTRICAL GENERATION (28.3%) 0 1000 2000 3000 1979 ENERGY BALANCE TELIDA GASOLINE + AV GAS 14.8% DIESEL 28.3% LEGEND _ ) — RESIDENTIAL () — SMALL COMMERCIAL (27) — PUBLIC BUILDINGS () — LARGE USERS (SCHOOL) ) — WASTE HEAT BLAZO — 0.9% PROPANE— 1.4% WOOD — 32.1% DIESEL — 225% TOTAL — 56.9% | | | 7000 8000 9000 | 10,000 G72 apa28: a3 ENERGY BALANCE - 1979 TELIDA Table 3.13 CONSUMER ENERGY FORM CONSUMED HEATING TRANSPORTATION / ELECTRICAL GENERATION DIESEL wOoD PROPANE BLAZO GASOLINE AV GAL DIESEL OTAL GAL CORDS POUNDS GAL GAL GAL | GAL 10® Btu TYPE NO. 10° Btu 10® Btu 10® Btu 10® Btu 10° Btu 10" Btu 10° Btu % of Total Residential 7 = 63 1,500 250 3,000 1,000 = 3 1,640 1,071 23 32 381 127 47.6 Smal] Commercial < = - = = = = a = Public Buildings 1 = =e e a = = = 34 34 1.0 Large User (school) 1 5,600 = 900 = Z 2 7,080 1,768 713 18 977 51.4 Total 9 5,600 65 2,400 250 3,000 1,000 7,080 3,442 7713 1,105 47 32 381 127 977 % of Total Btu 2225) 32.1 1.4 0.9 ab is | 357 28.3 100 Waste Heat 10° Btu 193 276 12 _8 286 _95 733 1,603 % of Total Btu eG 8.0 0.3 0.2 Sr 2.8) 21.4 46.6 Assumed Efficiency: Heating - 75% Transportation - 25% Electric Generation - 25% SECTION 4 ENERGY REQUIREMENTS FORECAST APA*32H14 SECTION 4 ENERGY REQUIREMENTS FORECAST INTRODUCTION The following paragraphs and tables outline the planned capital projects, economic activities forecast, and energy end use forecasts for the village of Telida.+ 1 Tables numbered as in original report. 4-1 APA*32H15 APA 22-A:M1 SECTION 4 ENERGY REQUIREMENTS FORECAST 13. Telida (a) Planned Capital Projects and Economic Activity Forecast Planned Capital Projects: Scheduled developments - Airport improvements Potential developments - Small-scale timber harvest Economic Activity Forecast: No substantial economic activity is forecast for the Telida area except for possibly a small-scale timber harvesting project to supply wood fuel for possible wood- fired electric generation in the late 1980's. (b) Population Forecast - Telida The population forecast is shown in the following Table 4.13 Table 4.13 Year 1970 1979 1982 1985 1990 2000 Population - 34 35 36 38 41 # Residences - 7 7 8 8 10 # Small commercial - 1 1 1 1 1 # Public users 7 1 1 1 2 2 # Large users - 1 1 1 1 1 Population growth rate - 1% 4-2 Cc ( ¢ ¢ ( ( ¢ Pm wn eR apa22: a3 The end uses of energy are shown in the following Tables 4.13a, 4. TELIDA ELECTRIC POWER REQUIREMENTS? . End Use Forecast and 4.13c. Table 4.13a 1979 Population 34 (1) Number of residential consumers 7 (2) Average kWh/mo/consumer = (3) MWh/year residential consumers (2) x (1) x 12 + 1000 7 (4) Number of small commer- cial consumers = (5) Average kWh/mo/consumer - (6) MWh/year small commer- cial consumer (4) x (5) x 12 + 1000 = (7) Number of public consumers - (8) Average kWh/mo/consumer - (9) MWh/year public consumer (7) x (8) x 12 + 1000 - 10) Large (LP) consumer 1 (school) 11) Average kWh/mo/LP 3,540 consumer# 12) MWh/year LP's (10) x (11) x 12 + 1000 42.5 13) System MWh/year (3)+(6)+(9)+(12) 42.5 14) System load factor 0.6 15) System demand kW (13)+8760+(14)x1000 8 Assumes electrification 1982. Telephone. Church. School at 1% growth rate. 4-3 1982 1 35 133 11.2 290 3.5 60 0.7 3,650 43.8 59.2 0.45 15 1985 36 160 15.4 330 4.0 68 0.8 3,760 45.1 65.3 0.45 17 1990 38 220 21.1 412 4.9 732 17.6 3,950 47.4 91.0 0.45 23 13b, 2000 41 10 415 49.8 640 737 1,137 27.3 4,365 52.4 137.2 0.45 35 apa22:c3 Table 4.13b TELIDA HEATING REQUIREMENTS? RESIDENTIAL CONSUMERS 1979 1982 1985 1990 2000 (1) Population 34 35) 36 38 41 (2) Number of resi- dential users 7 7 8 8 10 (3) Diesel - Average gal/mo/residence (6)+(2)+12 0 0 0 0 0 (4) Propane - Average lbs/mo/residence (7)+(2)+12 18 18 18 26 35 (5) Wood - Average cords/mo/residence (8)+(2)+12 0.75 0.75 0.75 0.72 0.65 (6) Diesel Gals 0 0 0 0 0 Btu x 10° (7) Propane _ Lbs 1,500 1,500 1,710 2,540 4,190 Btu x 10° 29 29 33 50 82 (8) Wood _ Cords 63 63 72 69 78 ; Btu x 10° 1,071 1,071 1,224 LS 1326) |) (9) Total Btu x 106 (6)+(7)+(8) 1,100 1,100 1,257 1,223 1,408 (10) Annual per capita consumption Btu x 106 (9)+(1) 32.4 31.4 34.9 3222 34.3 Assumes a one percent per year decrease in fossil fuel requirements beginning in 1986 due to implementation of passive solar heating and technical improve- ments in both building design and heating equipment. 4-4 (11) (12) (13) (14) (15) (16) (17) (18) (19) apa22-A: R12 Table 4.13c Small Commercial user Diesel Gals/Btu x 106 Public Buildings user Diesel Gals Btu x 106 Large users (school) Diesel equivalent (diesel + wood) Gals Btu x 10° Propane __ lbs Btu x 10° Subtotal Btu x 106 (16)+(17) Total Btu x 106 (9)+(12)+(14)+(18) TELIDA HEATING REQUIREMENTS? OTHER CONSUMERS 1979 791 1,891 1982 5,600 773 900 18 791 1,891 1985 791 2,048 1990 1 214 30 uo SI] wh ao ce ao a HI Oo 751 2,034 2000 474 65 474 65 681 2,219 Assumes a one percent per year decrease in fossil fuel requirements begin- ning in 1986 due to implementation of passive solar heating and technical improvements in both building design and heating equipment. 4-5 SECTION 5 RESOURCE AND TECHNOLOGY ASSESSMENT APA*32H16 SECTION 5 RESOURCE AND RECHNOLOGY ASSESSMENT A. ENERGY RESOURCE ASSESSMENT The energy resources which are determined to be available for the village of Telida are summarized in the following table. Inform- ation concerning approximate quantity, quality, availability, cost, source of data and important comments is included. The energy resources specifically addressed include diesel generation, wind, hydroelectric potential, waste heat utilization, and coal. While passive solar heating and energy conservation are not specifically addressed in the table, it is assumed these two energy conservation measures will be implemented in the village. Energy resources which are not available for use in Telida and are therefore not addressed include geothermal, timber, peat, solid waste, oi] and gas and tidal power. Oe APA*32H17 2-S APA22-A S12 Table 5.13 ENERGY RESOURCE Diesel fuel Wood fuel Coal fuel Waste Heat! Recovery Hydroelectric Potential Wind potential LOCATION Major supplier McGrath 10-mile radius N/A Ganes Creek ENERGY QUANTITY/AVAILABILITY 28.8x10® cu ft late 1980's N/A 30% of fuel used for electrical generation; upon installation of liquid cooled diesel engines. 1200 kW, 2838 mwh/yr RESOURCE ASSESSMENT TELIDA QUALITY #2 diesel 138,000 Btu/gal 14.6x10® Btu/cord N/A Recoverable heat 41,400 Btu/gal diesel equivalent. Villagers indicate insufficient wind in village for wind power. SOURCE OF Cost DATA $2.31/gal $16.75/10® Btu $132/cord* Appendix G $9.04/10° Btu N/A Appendix H - $450/kW installed Appendix D <$6.58/10® Btu> diesel fuel displaced 89 ,600/kW installed Reference #38 No wind data available. 1} Assumes $1.65/gal diesel fuel cost; 0.45 load factor, future diesel generator sets water cooled. 2 Lowered cost due to substantial road network surrounding Takotna. < > saving per million Btu recovered. COMMENTS Delivered cost at village. Cost assume heat delivery within 100 ft radius of plant. Availability varies with generator loading. Maintenance at $11/kW/yr. Hydro site would service Takotna, Ophir and McGrath. SECTION 6 ENERGY PLANS APA*32H18 SECTION 6 ENERGY PLANS A. INTRODUCTION The approach to the energy plans formulated for the village of Telida is explained in this section. Each plan is formulated to meet the forecasted electrical energy requirements of the village plus addi- tional related requirements, such as space heating, where appropriate. A base case plan using diesel generation is formulated for the village. This plan is used as the "control case" to determine the advantage or disadvantage of other alternatives as compared to diesel generation. Future village diesel generation additions assume that the local school, which has sufficient installed generation capacity, will provide its own back-up capability. The school will, however, rely on the central- ized village power plant for their primary supply of electrical power and energy. “A wood-fired binary cycle generation option is presented for the village of Telida. The wood used for fuel would assumed to be harvested within a 10-mile radius of the village. Diesel fuel oil-fired binary cycle generation is also possible, but provides no significant cost or technical advantage over diesel engine powered generation. Fuel oil-fired binary cycle generation is, therefore, not included in the formulated energy plan for the village. : A waste heat capture analysis is included with all options that use fossil fuels for electrical generation (i.e., diesel generation employing engine jacket water cooling, and binary cycle generation). Wind generation employing individual wind generators for residential consumers is also investigated for the village. APA*32H21 APA*32H20 SECTION 6 ENERGY PLANS Base Case Plan 1) 2) 3) Plan components - diesel and waste heat recovery Timing of system additions - Diesel - 1982 - 50 + 30 kW Waste heat equipment - 1983 - 50 kW Plan description - This plan assumes installation of liquid cooled diesel generation in 1982 (replacement for existing air cooled engine) and the continued use of diesel driven generators throughout the study and the implementation of waste heat recovery. Alternative Plan A 1) 2) 3) Plan components - diesel (liquid cooled 1982) and binary cycle generation using wood fuel and waste heat recovery Timing of additions - Diesel - 1982 - 50 + 30 kW Binary cycle - 1989 - 50 kW Waste heat equipment - 1983 - 50 kW, 1989 - 50 kW Plan description - This plan assumes construction of wood-fired binary cycle generation facilities in the late 1980's as a replacement for diesel genera- tion and the implementation of waste heat recovery. APA*32H21 SECTION 6 ENERGY PLANS Alternative Plan B 1) Plan component - Wind generation 2) Timing of additions - Diesel - None Wind generators - 1982 - 7 - 1.5 kW WECS; 1985 1-1.5 kW WECS; 2000 2-1.5 kW WECS 3) Plan description - This plan assumes individual 1.5 kW wind generators for residential users and the continued use of the presently installed air-cooled diesel generator for supplying power to the school. APPENDIX A DESCRIPTION OF SELECTED TECHNOLOGIES APA*®32H22 A.1 DIESEL a. General Description 1) 2) APA*32C35 Thermodynamic and engineering processes involved In the diesel engine, air is compressed in a cylinder to a high pressure. Fuel oi] is injected into the compressed air, which is at a temperature above the fuel ignition point, and the fuel burns, converting thermal energy to mechanical energy by driving a piston. Pistons drive a shaft which in turn drives the generator Current and future availability Diesel engines driving electrical generators are one of the most efficient simple cycle converters of chemical energy (fuel) to electrical energy. Although the diesel cycle in theory will burn any combustible matter, the practical. fact of the matter is that these engines burn only high grade liquid petroleum or gas, except for multi-thousand horsepower engines which can burn heated residual oi]. Diesel generating units are usually built as an integral whole and mounted on skids for installation at their place of use. A.2 BINARY CYCLE FOR ELECTRICAL GENERATION a. General Description 1) 2) APA*32C36 Thermodynamic and engineering processes involved In the binary conversion process, a heated primary fluid of insufficient quality for direct use in electrical production passes through a heat exchanger to transfer heat to a working fluid. The working fluid has a lower boiling point than water and is vaporized in the heat exchanger. The vaporized working fluid then expands through a turbine or cylinder piston arrange- ment is condensed, and returns to the heat exchanger. The primary fluid is returned to its heat source following heat exchange. Current and future availability Current commercial availability is restricted to unit sizes in excess of village power requirements as determined in this study. Binary cycle generation equipment in unit sizes suit- able for village application is not expected to be available until the late 1980's. A-2 A.3 HYDROELECTRIC GENERATION a. General Description ds APA*32C37 Thermodynamic and engineering processes involved In the hydroelectric power development, flowing water is directed into a hydraulic turbine where the energy in the water is used to turn a shaft, which in turn drives a gener- ator. In their action, turbines involve a continuous trans- formation of the potential and/or kinetic energy of the water into usable mechanical energy at the shaft. Water stored at rest at an elevation above the level of the turbine (head) possesses potential energy; when flowing, the water possesses kinetic energy as a function of its velocity. The return of the used water to the higher elevation necessary for funct- jioning of the hydroelectric machinery is powered by the sun to complete the cycle - a direct, natural process using solar energy. The ability to store water at a useful elevation makes this energy supply predictable and dependable. Current and future availability Hydroelectric developments in the United States, as of January 1978, totaled 59 million kilowatts, producing an estimated average annual output of 276 billion kilowatt hours according to the U.S. Department of Energy (DOE). Hydropower provides about 10% of Alaska's electric energy needs. Developments range in size from over a million kilowatts down to just a few kilowatts of installed capacity. Hydropower is a time proven method of generation that offers unique advantages. Fuel cost, a major contributor to thermal plant operating costs, is eliminated. ASS A.4 WIND ENERGY CONVERSION SYSTEMS (WECS) a. General Description 1) 2) APA*32C38 Thermodynamic and engineering processes involved The thermodynamic process involved stems from the sun, the primary energy source which produces the wind. This wind energy cannot be stored, is intermittent, somewhat unpredict- able and thereby undependable. The process then relies , on wind flow over an air foil assembly to create differential pressures along the air foil. This differential pressure results in rotation of the assembly around a fixed axis to which it is attached. Power from the wind is transmitted through the connection shaft and accompanying gear box to an electrical generator. Three types of generators are presently in use with wind energy systems. These are the DC generator, the AC induction generator and the AC synchronous generator. Of the three types, the AC induction generator is the most widely used because of its . simplicity and low cost. An induction generator is not a stand- alone generator and must be connected to an external power system of relatively constant frequency and voltage to operate properly. Current and future availability Availability of the wind at useful velocities require long term records to estimate the potential energy. Lesser records provide less credible estimates. Availability of WECS machinery in smal] size units in the 1.5 kW to 20 kW range is good. Large units in the 100-200 kW range are currently undergoing tests in both the government and private sector and should be available in the near future. Demonstrations of multi-megawatt sizes are in process. A-4 A.5 DIESEL WASTE HEAT RECOVERY a. General Description 1) 2) APA*32C39 Thermodynamic and engineering processes involved The present use of fossil fuels (coal, gas, oi1) in Alaska (as elsewhere) to produce more useful forms of energy (heat, electricity, motive power) is less than 100 percent efficient. For example, if a machine burns a certain quantity of fossil fuel and produces useful output (shaft horsepower, electrical energy, steam, useful hot water or air for space heating) equivalent to 30% of the fuel burned, the energy represented by the remaining 70% of the fuel will appear as unused or "waste" heat. Such heat most often appears as hot exhaust gas, tepid to warm water (65°F-180°F), hot air from cooling radiators, or direct radiation from the machine. Diesel waste heat can be recovered from engine cooling water and exhaust, or either source separately. The waste heat is typically transferred to a water-glycol circulating system in Alaskan applications. The heated circulating fluid can be used for space, water, or process heating where temperatures of the waste hear are suitable. Current and future availability Recovery of diesel waste heat in Alaska is growing as a result of sharp increases in diesel fuel cost. Recovery of jacket water heat only is most common in Alaska. Diesel waste heat availability is directly related to the location and operating cycles of the engine installations. A.6 PASSIVE SOLAR HEATING a. General Description Passive solar heating makes use of solar energy (sunlight) through energy efficient design (i.e. south facing windows, shutters, added insulation) but without the aid of any mechanical or electrical inputs. Space heating is the most common application of passive solar heating. Because such solar heating is available only when the sun shines its availability is intermittent (day-night cycles) and variable (winter-summer-cloudy-clear). APA*32C40 A.7 CONSERVATION a. General Description 1) Ce APA*32C41 Thermodynamic and engineering processes involved Conservation measures considered here are mainly classified as "passive". Passive measures are intended to conserve energy with- out any further electrical, thermal, or mechanical energy input. Typical passive measures are insulation, double glazing or solar film, arctic entrances and weather stripping. Energy conservation characteristics of some passive measures degrade with time, which must be considered in the overall evaluation of their effectiveness for an intended life cycle. Other conservation measures includes improvement in efficiency of utilization devices (such as motors) and "doing without" energy by disciplines (turning off lights, turning down thermostats). Current and future availability Materials and schemes to implement passive measures are commer- cially available and increasing in use all over the United States due to the rapidly escalating cost of energy.