Loading...
HomeMy WebLinkAboutCrooked Creek Reconnaissance Study Of Energy Requirements & Alternatives-Crooked Creek 1981 OF ENERGY REQUIREMENTS & ALTERNATIVES FOR CROOKED CREEK ; * Bot nt aarti a eT 4) a INTERNATIONAL ENGINEERING COMPANY, INC. A MORRISON-KNUDSEN COMPANY ROBERT W. RETHERFORD ASSOCIATES DIVISION Ls NC ASRA POWERAULHORI Ly = | CROOKED CREEK 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 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.I.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 ano fF WHY 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 Page Led 2.0. 3e1 4.1 Ded 652 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 Crooked Creek supplement represents a brief summary of the most perti- nent facts and findings contained in the original report which relate to the village of Crooked Creek. 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 Crooked Creek include: ? i) Diesel generation 2) Waste Heat Recovery 3) Binary Cycle generation using wood fuel 4) Passive solar heating 5) Energy conservation 1 See Appendix A for brief description of technologies listed. Sd. APA34*E1 BARROW OCR, Noatak River 1 BUCKLAND 2 HUGHES 3. KOYUKUK 4 RUSSIAN MISSION cle 5 SHELDON POINT “le 6 CHUATHBALUK Roy » 7 CROOKED CREEK Mountains \ 8 NIKOLAI \ 9 RED DEVIL talens Tavera Plateau | 10 SLEETMUTE | 11 STONY RIVER teks a 12 TAKOTNA rs Minchuming —°** Rongy \ 13 TELIDA 13 \ 8 ¢ Suslng RY Copp4, Oiniiet © Totkesme ont Orange | Mountain 0 (Hill *OnG61 pis jin | Y i (C ANCHORAGE \ vy Y cits s oO ott f u “4 9 pV of YAKUTAT q ° Sc v Gulf of Alaska . . g . Bris Boy - isto! KODIAK pACIFIC OCEAN gs pnv® 4 vst C28 O94 FIGURE 1.1 OSS % ° 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 Crooked Creek. 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 Crooked Creek The diesel generation plus binary generation with waste heat energy plan averaged approximately 5 percent greater cost than the diesel generation plus waste heat recovery plan for Crooked Creek. This small variation in cost between the two energy plans represents an insignificant difference in a reconnaissance level study, where costs cannot be precisely determined, and should not be construed to indicate a definite cost advantage of one plan over another. 1-3 APA34*E3 ia CROOKED CREEK 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 2339-260.2 2453-226.3 N/A N/A SECTION 1 SUMMARY AND RESULTS 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. Zz. 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 Crooked Creek in order of preference to be: 1) diesel electric plus waste heat 2) diesel plus binary cycle generation with waste heat APA34%E5 9-1 APA 28P1 Table 1.2 Factor (A) Econo! mic (Present Worth) (B) Environmental qQ) (2) (3) (4) (5) (6) (7) (8) Envir (C) Techn ) (2) (3) TECHNICAL OVERALL R Community Preference Infrastructure Timing Air Quality Water Quality Fish and Wildlife Land Use Terrestrial Impacts TOTAL onmental Ranking ical Safety Reliability Availability TOTAL RANKING ANKING Diesel Electric + Waste Heat ERSTE ROH NSIT EIT CoIl to Np uo Diesel + Local Hydro w/wo Electric Heat EVALUATION MATRIX Diesel + Diesel + Waste Heat Binary Generation Supplemental Coal and/or Wood Wind With Waste Heat Generation jae mR ea Vw ' w MN lo nm ' 12 SECTION 2 RECOMMENDATIONS APA34*E6 SECTION 2 RECOMMENDATIONS A. GENERAL Analysis of the 20-year economic, technical and environmental evaluations indicate the two most promising energy plans for the village of Crooked Creek 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. 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 Crooked Creek. It is recommended, therefore, that a study be conducted to determine the feasibility of utilizing waste heat in the village of Crooked Creek. 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. This plan averages approximately 5 percent greater costs than the recommended plan (20-year economic evalu- ation). Because the uncertainties in the costs associated with this alternative, such as the cost of wood fuel, equipment cost, etc., which 21 APA34*E7 SECTION 2 RECOMMENDATIONS can not at present be as precisely determined as for the 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 Crooked Creek, 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. COSTS FOR FURTHER STUDY Approximate costs for determining of feasibility of the two most attractive energy resources for the village of Crooked Creek are: ° Waste heat recovery - approximately $2500 e Binary cycle generation - approximately $2,000,000 which would include the cost of constructing and operating a demonstration plant in Alaska. E. 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. 2-2 APA34*E8 SECTION 3 EXISTING CONDITIONS AND ENERGY BALANCE APA34*E9 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: The village of Crooked Creek is located on the north bank of the Kuskokwim River at its confluence with Crooked Creek, 50 miles northeast of Aniak in the Kilbuk-Kuskokwim Mountains. A trading post was established in 1914 a short distance upriver from the mouth of the creek at an area known as the "Upper Village”. The . settlement of Eskimo and Ingalik Indians at the “lower village" downriver of the junction of Crooked Creek and the Kuskokwim River was noted as early as 1850. The village remains divided to this day with a community center on each side of Crooked Creek. Pursuant to the Alaska Native Claims Settlement Act of 1971, Crooked Creek village corporation is entitled to 92,160 acres of Federal land. When Crooked Creek village Corporation merged with 9 other Middle Kuskokwim a1 APA34*E10 APA34*E11 SECTION 3 EXISTING CONDITIONS AND ENERGY BALANCE village corporations, these entitlements passed to TKC for consolidated ownership and management. Calista Corporation is the regional corporation. Population: In 1939 a population of 48 was recorded for Crooked Creek. In 1950 the population was 43. Between 1950 and 1960 the population increased by 92 percent to a population of 92. Over the next ten years, a decrease in population of 36 percent was experienced, for a total of 59 year-round residents in 1970. A 1979 estimate made by the village council shows 124 residents. According to -the 1970 census, 93 percent of the population were Eskimo or Ingalik Indian. In 1979, the average number of members per household in the community was 4.0 persons. Economy: Year-round employment opportunities in Crooked Creek are limited. Government programs, the Kuspuk School District, which employes 5 full-time employees, and a minimum of support services provide the only permanent positions in the village. Some seasonal employment is available during the summer months. The largest seasonal employer is the Alaska Village Council President (AVCP) Employment and Training Program, which employs 7 - 10 village residents during the summer months. Income from these enterprises is supplemented by public assistance payments and the residents' subsistence activities. Crooked Creek residents hunt beaver, muskrat, game birds, rabbit, moose, caribou and waterfowl. Income is also derived from trapping and the sale of pelts. During the summer months residents fish for salmon and other species of fish. In the fall, cranberries, blue- berries and other varieties of berries are harvested. 3-2 APA34*E12 SECTION 3 EXISTING CONDITIONS AND ENERGY BALANCE Government: Crooked Creek is not incorporated as a Municipality under State law. Crooked Creek's Native population is represented by a 5-member traditional council. Transportation: The community's location on the Kuskokwim River allows barge and small boat travel as well as access by air. Fuel and bulk supplies are transported upriver to Crooked Creek by river barge. Passengers, other cargo and mail arrive primarily by air. A dirt road approximately 1.5 miles long, connects the lower village, upper village and the airport. A sus- pension bridge over Crooked Creek provides for only pedestrians, snowmachine and motorbike access between the two parts of the village. No roads connect Crooked Creek with surrounding communities. In the winter, when the river freezes, villagers rely on snowmachines for transportation. ENERGY BALANCE Wood is the primary fuel used for residential and small commercial heating requirements. Fuel oi] is used to supplement as necessary. Public buildings and the school use fuel oil to satisfy their heating needs. Fifty-seven and four-tenths percent of the energy used in the village is for heating, 30.2 percent is used for transporation and 12.4 percent is used for electric generation. Graph 3.7 illustrates by consumer category the type and percentages of energy forms used in the village. Table 3.7 tabu- larizes this data in additional detail. 3-3 APA34*E13 SECTION 3 EXISTING CONDITIONS AND ENERGY BALANCE EXISTING POWER AND HEATING FACILITIES Electric Power: No centralized power generation facility exists in Crooked Creek. The school generators (two 50-kW units) provide power to the school, satellite earth station and three private consumers. The community hall and clinic are lighted using a small gasoline generator as necessary. Planning for electrification of Crooked Creek is currently in progress. Electrification is anticipated for the summer of 1981. Heating: Heating for residential and smal] commercial consumers is primarily provided by wood, supplemented by fuel oil. Residential uses average 7.5 cords of wood and 135 gallons of fuel oil] per year. The heating require- ments of public buildings and the school are provided by fuel oil. Fuel Storage: Diesel, bulk fuel oi] storage capacity in the community (school and village) is approximately 50,400 gallons (reference 27). 3=4 GRAPH 3.7 1979 ENERGY BALANCE CROOKED CREEK EFFICIENCIES ASSUMED: LEGEND _ HEATING — 75% Ree] — RESIDENTIAL TRANSPORTATION — 25% () — SMALL COMMERCIAL ELECTRICAL GENERATION — 25% [=] — PUBLic BUILDINGS (HN —_ LARGE USERS (SCHOOL) WN) — «WASTE HEAT TOTAL ENERGY (100%) 2.5% HEATING (57.4%) BLAZO — 18% PROPANE— 0.4% WOOD — 31.1% DIESEL — 24.1% TOTAL — 57.4% TRANSPORTATION (30.2%) GASOLINE + AV GAS 30.2% ELECTRICAL GENERATION (12.4%) 5 DIESEL 12.4% | | | | | | | | | | | | | | | | | | 0 2000 4000 6000 8000 10,000 12,000 14,000 16,000 18,000 BTU x 108 20,000 9-€ apa28: al3 ENERGY BALANCE - 1979 CROOKED CREEK Table 3.7 CONSUMER ENERGY FORM CONSUMED HEATING TRANSPORTATION ELECTRICAL _ DIESEL wooD PROPANE BLAZO GASOLINE AV GAL DIESEL TOTAL 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 31 4,200 233 1,600 1,850 17,050 1,200 - 7,124 580 3,961 31 235 2,165 152 55.8 Smal] Commercial 3 2,200 = = - = 12,050 : 1,834 304 1,530 14.4 Public Buildings 2 1,100 - - - - 1,200 318 152 166 2.5 Large User (school) 1 14,760 = 1,200 . = 7 10, 300 3,480 2,036 23 1,421 27.3 Total 37 22,260 233 2,800 1,850 17,050 13,250 11,500 12,756 3,072 3,961 54 235 2,165 1,682 1,587 % of Total Btu 24.1 31.1 0.4 1.8 17. 0 13.2 12.4 100 Waste Heat 10° Btu 769 990 14 59 1,624 1,262 1,190 5,908 X of Total 6.0 7.8 Oal 0.5 12.7 9.9 9.3 46.3 1 Rental outlets and flying service Assumed Efficiency: Heating - 75% Transportation - 25% Electric Generation - 25% SECTION 4 ENERGY REQUIREMENTS FORECAST APA34*E15 SECTION 4 ENERGY REQUIREMENTS FORECAST A. INTRODUCTION The following paragraphs and tables outline the planned capital projects, economic activities forecast, and energy end use forecasts for the village of Crooked Creek. ? 1 Tables numbered as in original report. 4-1 APA34*E16 APA22-A:G1 We Crooked Creek SECTION 4 ENERGY REQUIREMENTS FORECAST (a) Planned Capital Projects and Economic Activity Forecast Planned Capital Projects: Scheduled developments - New school building Electrification Airport improvements Potential developments - Timber harvest Peat harvest Farewell coal field Economic Activity Forecast: area is greatly dependent on timber, coal field development, become operational would provide mostly providing lower cost energy to consumers. before the The economic activity in the peat and Farewell none of which is anticipated to late 1980's 1990's. It is expected that these resource developments or early indirect benefits to the area by No significant economic activity is forecast for the immediate future. (b) Population Forecast - Crooked Creek The population forecast is shown in the following Table 4.7 Year Population # Residences # Small commercial # Public users # Large users Population growth 1970 59 Table 4.7 1979 1982 124 132 afl 32 3 3 2 3 1 1 - % 1985 144 1990 167 44 2000 224 56 apa22:al3 C. End Use Forecast The end uses of energy are shown in the following Tables 4.7a, 4.7b, and 4.7c. Table 4.7a CROOKED CREEK ELECTRIC POWER REQUIREMENTS? 1979 1982 1985 1990 2000 Population 124 132 144 167 224 (1) Number of residential . consumers o 26 36 42 56 (2) Average kWh/mo/consumer Ss 133 160 220 415 (3) MWh/year residential consumers (2) x (1) x 12 + 1000 - 41.5 69.1 110.9 278.9 (4) Number of small commer- cial consumers = 3 3 4 6 (5) Average kWh/mo/consumer = 848 968 1,205 1,872 (6) MWh/year small commer- cial consumer (4) x (5) x 12 + 1000 = 30.5 34.8 5738) 134.8 (7) Number of public consumers 1 3 5 A 9 (8) Average kWh/mo/consumer 850 970 : 1,107 1,379 2,142 (9) MWh/year public consumer (7) x (8) x 12 + 1000 L0v2 34.9 66.4 115.8 231.3 (10) Large (LP) consumer 1 1 I 1 1 (LP) (11) Average kWh/mo/LP 7,300 9,971 % 10,896 12,631 16,975 consumer 2 (12) MWh/year LP's (10) x (11) x 12 + 1000 87.6 119.7 130.8 151.6 203.7 (13) System MWh/year (3)+(6)+(9)+(12) 97.8 226.6 801.1 436.1 848.7 (14) System load factor 0.6 0.45 0.45 0.45 0.50 (15) System demand kW (13)+8760+(14)x1000 19 57 76 Ly 194 1 Electrification scheduled for summer 1981. 2 School at 3% Growth Rate. 3 New School Building. 4-3 apa22:c13 Table 4.7b CROOKED CREEK HEATING REQUIREMENTS?# RESIDENTIAL CONSUMERS 1979 1982 1985 1990 2000 (1) Population 124 132 144 167 224 (2) Number of resi- dential users 31 32 38 44 56 (3) Diesel - Average gal/mo/residence (6)+(2)+12 11 11 11 11 10 (4) Propane - Average 1bs/mo/residence (7)+(2)+12 4 4 9 17 30 (5) Wood - Average cords/mo/residence (8)+(2)+12 0.63 0.63 0.63 0.59 0.54 (6) Diesel Gals 4,200 4,340 5,150 5,670 6,530 Btu x 105 580 599 711 182 901 (7) Propane __Lbs 1,600 1,685 4,005 8,815 20,310 Btu x 10° 1 33 78 172 396 (8) Wood _ Cords 233 240 286 313 363 Btu x 105 3,961 4,080 4,862 5,321 6,171 (9) Total Btu x 106 (6)+(7)+(8) 4,572 4,712 5,651 6, 275 7,468 (10) Annual per capita consumption Btu x 106 (9)+(1) 36.9 35.7 39.2 37.6 33.3 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: R6 CROOKED CREEK HEATING REQUIREMENTS?! OTHER CONSUMERS Table 4.7c 1979 Small Commercial 3 user Diesel 2200 Gals/Btu x 106 304 Public Buildings user 2 Diesel _ Gals 1100 Btu x 10° 152 Large users (school) 1 Diesel equivalent (diesel + wood) Gals 14,760 Btu x 10° 2,036 Propane lbs 1200 Btu x 106 23 Subtotal Btu x 10° (16)+(17) 2059 Total Btu x 10& (9)+(12)+(14)+(18) 7,088 1982 1985 1990 3 3 4 2200 2200 2639 304 304 364 3 5 7 1650 3900 5848 228 538 807 1 1 1 20,1602 20,160 19,172 2,782 2,782 2,646 1200 1200 1141 "23 23 22 2805 2805 2668 8,049 9,298 10,114 2000 3315 457 7232 9398 1033 2415 11,339 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. New school building. SECTION 5 RESOURCE AND TECHNOLOGY ASSESSMENT APA34*E17 SECTION 5 RESOURCE AND RECHNOLOGY ASSESSMENT A. ENERGY RESOURCE ASSESSMENT The energy resources which are determined to be available for the village of Crooked Creek 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 specif- ically addressed include diesel generation, wind, hydroelectric potential, waste heat utilization, timber 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 Crooked Creek and are therefore not addressed include geothermal, peat, solid waste, oil and gas and tidal power. APA34*E18 e-s APA22-A S6 Table 5.7 ENERGY RESOURCE Diesel fuel Wood fuel Coal fuel Waste Heat! Recovery Hydroelectric potential Wind potential LOCATION Major supplier Bethel Middle Kuskokwim Healy, Alaska QUANTITY/AVAILABILITY 167x10® cu ft late 1980's Late 1980's 30% of fuel used for electrical generation; upon installation of power plant. N/A “1 Assumes $1.45/gal diesel fuel cost 0.45 load factor. < > saving per million Btu recovered. ENERGY RESOURCE ASSESSMENT CROOKED CREEK QUALITY #2 diesel 138,000 Btu/gal 14.6x10® Btu/cord 8500 Btu/Ib 17x10® Btu/ton Recoverable heat 41,400 Btu/gal diesel equivalent N/A 8 mph average annual wind speed. SOURCE OF COST DATA $1.45/gal United $10.51/10® Btu Transportation Bethel. $92/cord Appendix G $6.30/10® Btu $110/ton Appendix H $6.47/10° Btu $450/kW installed Appendix D <$5.13/10® Btu> diesel fuel displaced N/A Reference #38 - Regional Profiles Delivered cost at village Delivered cost at village. Delivered cost at village. Cost assume heat delivery within 100 ft radius of plant. Availability varies with generator loading. Maintenance at $11/kW/yr. Average annual wind speed insufficient for wind generation. SECTION 6 ENERGY PLANS APA34*E19 SECTION 6 ENERGY PLANS A. INTRODUCTION The approach to the energy plans formulated for the village of Crooked Creek 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 Crooked Creek. It is assumed the wood required for fuel would be supplied from timber harvested along the Kuskokwim River and its tributaries. 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). 6-1 APA34*E20 APA 32/A15 SECTION 6 ENERGY PLANS Base Case Plan 1) 2) Plan components - Diesel and waste heat recovery Timing of system additions Diesel - 1981 - 60 kW + 100 kW; 1989 - 100 kw Waste heat equipment 1983 - 100 kW; 1989 - 100 kW Plan description - This plan assumes 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 and binary cycle generation using wood fuel and waste heat recovery. s Timing of additions - Diesel - 1981 - 60 kW + 100 kW Binary units - 1989 - 200 kW Waste heat equipment - 1983 - 100 kW, 1989 - 200 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. 6-2 APPENDIX A DESCRIPTION OF SELECTED TECHNOLOGIES APA34*E21 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-1 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 a5 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- joning 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. A.4 WIND ENERGY CONVERSION SYSTEMS (WECS) as 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 small 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. ASS 6 PASSIVE SOLAR HEATING as 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 1d) 2) 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.