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HomeMy WebLinkAboutKing Cove Reconnaissance Study of Energy Requirements & Alternatives 7-1981VIL-C 002 3 Hes SE: King = i HH a Oo. eee EF >= OQ eee ae oO _ > = a ee a Cc ca — ae ay n <x = x Summary Reconnaisance Study of Energy Requirements & Alternatives for King Cove PLEASE DO NOT REMOVE FROM OFFICE! Prepared For July 1981 Alaska Power Authority CH2M gBHILL PROPERTY GF: Alas*a Power Authority G34 W. Sth Ave. Anchoragsa, Alaska 99501 ALASKA POWER AUTHORITY Summary Reconnaisance Study of Energy Requirements & Alternatives for King Cove Prepared For July 1981 Alaska Power Authority CH2M&EHILL ALASKA POWER AUTHORITY K14238 an MM PREFACE This summary contains the results of a study evaluating energy requirements and alternative electricity sources for the com- munity of King Cove on the Alaska Peninsula. The study was performed as part of a larger study that included four com- munities on Kodiak Island and two communities on or near the Alaska Peninsula. This study is described in a report titled Reconnaissance Study of Energy Requirements and Alternatives for Akhiok, King Cove, Larsen Bay, Old Harbor, Ouzinkie, Sand Point, issued in June 1981. It was authorized by the State of Alaska, Department of Commerce and Economic Develop- ment, Alaska Power Authority, in a contract with CH2M HILL signed October 9, 1980. iii an MM RECOMMENDATIONS King Cove is on the Alaska peninsula and has a year-round population of approximately 460. Peter Pan Seafoods, Inc., maintains a large seafood processing plant in King Cove and is the primary source of economic activity in the city. The community has grown in recent years. As a result of con- tinued economic activity and the availability of newly con- structed housing, future population growth is anticipated. A city-owned, diesel-electric generation plant is being in- stalled near the harbor. The plant will serve only the city and school and will consist of one new 300-kilowatt (kW) diesel engine generator (now being installed), one new 300-kW generator (on order), and one planned 300-kW generator. Cur- rent peak electrical requirements for the city and school are 170 kW; these are expected to grow to 340 kW by the year 2000. The proposed Delta Creek hydropower project would be located near the village airstrip, with a rated capacity of 330 kw. It would require an initial investment of approximately $4.0 million (at January 1981 prices). The Delta Creek project would be lower in cost, over a 50-year planning period, than continued central diesel electric generation. Between 1985 and 1997 excess electricity from the Delta Creek plant could be used by the processing plant, thus displacing diesel gen- eration. If excess electricity could not be sold, the proj- ect would be less attractive. A more detailed investigation is needed to determine the feasibility of the Delta Creek project. This would include detailed aerial mapping and streamflow measurement programs. Data collected from such programs could be used to refine project configuration and cost estimates. A streamflow measurement program would take at least 1 year. The feas- ibility investigation would cost approximately $80,000 to $120,000. A more detailed investigation is needed to determine the feasibility of a weatherproofing and insulation program, primarily for older housing. This investigation would include a more detailed characterization of current insula- tion levels, the general condition of the existing housing, an assessment of heating requirements, and an assessment of both the costs and expected results of alternative conser- vation programs available to the community. Such an inves- tigation would cost approximately $20,000. CONTENTS Preface Recommendations 1 Introduction 2 Existing and Projected Energy Requirements Existing Electrical Generation Facilities Annual Energy Use Demographic and Economic Forecast Energy Requirements Forecast 3 Alternative Sources of Energy Small Hydroelectric Generation Tidal Generation Induction Wind Generation Waste Heat Recovery From Central Diesel Engine Generators Heat Energy Conservation Peat Combustion for Electrical Generation Coal Combustion for Electrical Generation Solar Energy (Active Solar Heating and Electrical Generation) Single Wire Ground Return Electricity Transmission Preferred Sources of Electricity 4 Evaluation of Alternative Electricity Supply Plans Appendix: Economic Evaluation of Alternative Plans Environmental Evaluation of Alternative Plans Technical Evaluation of Alternative Plans Conclusions Detailed Description of Preferred Electricity Sources vii hb DPW WW oonn~ 10 10 10 11 11 13 13 13 16 16 17 TABLES 1 Forecast of Annual Energy Requirements for King Cove 6 2 Preliminary Evaluation of Alternative Energy Sources for King Cove 12 3 Alternative Electricity Supply Plans for King Cove 14 4 Evaluation of Alternative Electricity Supply Plans for King Cove 15 FIGURES 1 Annual Energy Balance for King Cove 5 ix WM Chapter 1 MM INTRODUCTION Alternative sources of electricity for the community of King Cove on the Alaska Peninsula were identified and evaluated in the study summarized by this report. The sources recom- mended for further study could help the community reduce its dependence on expensive and often scarce diesel fuel for electrical generation. The purpose of the study was to recommend a series of activ- ities that will result in the identification of feasible alternative sources of electricity. The sources studied include wind generation, peat and coal combustion for elec- trical generation, small hydroelectric generation, tidal generation, solar-electric generation, and continued use of centralized or decentralized diesel generation. Waste heat recovery and the conservation of building heat were also evaluated. Establishment of the feasibility of a specific source was beyond the scope of the study. Information about these sources formed the basis for prep- aration of alternative plans to meet King Cove's future demands for electricity. Electrical demands of the school were included in these plans. Each plan was assessed on the basis of its technical, economic, environmental, social, and institutional characteristics. The assessments were performed in accordance with the procedures and assumptions established by the Alaska Power Authority. Further information about this study is contained in a report titled Reconnaissance Study of Energy Requirements and Alterna- tive for Akhiok, King Cove, Larsen Bay, Old Harbor, Ouzinkie, Sand Point, issued by the Alaska Power Authority in June 1981. MM Chapter 2 MM EXISTING AND PROJECTED ENERGY REQUIREMENTS The CH2M HILL project team visited King Cove during October 1980 and, through discussions and meetings with local resi- dents, obtained information on current living conditions, housing, household fuel consumption, employment, subsistence activities, and concerns about local resources. An inspec- tion of the existing generation system was conducted to determine the nature and condition of the plant. Represen- tatives of Peter Pan Seafoods provided information about processing plant operations and fuel consumption. Additional information was obtained from published sources and inter- views with local planners. EXISTING ELECTRICAL GENERATION FACILITIES The City of King Cove owns and operates a central generation and distribution system that serves the community residences, small commercial establishments, and the school. The city currently operates a 250-kilowatt (kW) GMC 12V71 unit (in- stalled in 1979) and a rebuilt 200-kW GMC. 8V1271 unit and has a 600-kW unit that is not operable. The old system will soon be replaced by two 300-kW Caterpillar units, one of which is still on order. A separate generating system owned by Peter Pan Seafoods supplies electricity to the seafood processing plant and all camp employee housing. This plant, consisting of one 250-kW, one 1,000-kW, and four 750-kW units, is in good operating condition. The Peter Pan plant also serves the entire community when the city generating plant is not operating. The electricity is distributed over a 7,200-volt, 3-phase system. Residents expressed concern over what they believed was the high cost of electricity in King Cove. It appeared, how- ever, that most homes had a wide range of electrical appli- ances. The effect of the relatively high cost of electricity on the standard of living of local residents was varied, depending largely on a household's income. Residents hope that the changeover to a new generation plant will decrease their costs or at least increase the system's reliability. ANNUAL ENERGY USE Fairly complete fuel consumption data are available for King Cove; however, several use categories had to be further devel- oped. Annual fuel delivery records show consumption of diesel fuel by the City of King Cove and Peter Pan Seafoods, Inc. It was assumed that the entire annual delivery (1,380 gallons) of diesel fuel to the city was for generation. Use of a conversion factor of 10 kilowatt-hours (kWh) per gallon resulted in estimated city generation of 756,000 kWh per year. A load factor of 50 percent was used to calculate the peak load of 170 kW. End uses of electricity include light- ing and appliances such as refrigerators, freezers, televi- sions, washers, and dryers. Seventy percent of total fuel consumption by Peter Pan Sea- foods was assumed to be for generation (7,090 barrels) and 30 percent for "other" (3,680 barrels). (Diesel fuel classi- fied as other is primarily for fueling fishing vessels.) A conversion factor of 10 kWh per gallon was used to estimate cannery generation of 3,900 megawatt-hours per year. Total annual deliveries of heating fuel were recorded for the school, the chapel, several commercial establishments, and the cannery. Peter Pan Seafoods sells heating fuel to residents of King Cove and uses the remainder for cannery consumption. The amount of cannery heating fuel distributed annually to residents was estimated to be 165 gallons per household per month in the summer and 330 gallons per house- hold per month in the winter. The resulting amount, plus deliveries to the chapel and commercial establishments, totaled 5,400 barrels for city heating. The amount of heating fuel remaining for use at the cannery, 3,040 bar- rels, was classified as "cannery, other." End uses of heating fuel include heating, cooking, and water heating. Propane is occasionally used for cooking. Figure 1 summarizes energy information for King Cove. DEMOGRAPHIC AND ECONOMIC FORECAST The population of King Cove is projected to increase at an average annual rate of 2 percent between 1981 and 2000. This rate of increase is conservative in comparison with historical changes in population in the community. The housing stock is expected to increase at a slightly higher rate than popu- lation during the next 20 years. Projected increases have been extrapolated from estimates provided by local planners. This relationship between population and housing projections allows for future decreases in the average household size and an increase in housing market flexibility (i.e., a vacancy rate slightly greater than zero). The preceding projections of population and housing require- ments are dependent on future levels of economic activity and land availability. As long as it is difficult for indi- viduals to acquire and own land for home sites, growth in housing (and perhaps population) will be limited. It has been assumed, however, that within the next 4 years individ- uals will be able to acquire home sites. IMPORTS MOTOR GAS 7,000 GAL DIESEL FUEL t—11,508 bbl HOME HEATING 9,306 bbl FUEL END USE VEHICLE AND . THER USE 8,375 x 10° Btu NON-RECOVERABLE GENERATION WASTE HEAT 31,783 x 10° Btu RECOVERABLE GENERATION WASTE HEAT 19,400 x 10° Btu CITY GENERATION 755,900 Kwh CANNERY GENERATION 3,900,000 Kwh ITY HEATING 42,768 x 10° Btu SCHOOL HEATING 1,782 x 10° Btu CANNERY MISC. USE 24,061 x 10° Btu ie ony 29,153 x 10° Btu FIGURE 1 ANNUAL ENERGY BALANCE FOR KING COVE Employment opportunities are expected to increase during the next two decades. Future opportunities will probably come from fishing and the growth of local business and government. The economy of King Cove is now almost totally dependent on the local seafood processing plant. The village's growth has paralleled fishing industry and processing plant development. Oil and gas development on the outer continental shelf might provide additional opportunity for local economic develop- ment. A lease sale on the northern Aleutian Shelf (Bristol Bay area) is scheduled for October 1983. If these opportunities are not realized, and if the amount of land available for private use does not increase, future population and housing growth might be significantly lower than projected. ENERGY REQUIREMENTS FORECAST Annual energy requirements for King Cove were projected to the year 2000 (Table 1). Fuel use and electrical generation for all uses except seafood processing plant operations are projected to grow 5 percent annually from 1981 to 1990 and 2 percent annually from 1990 to 2000. Since it is not pos- sible to forecast the level of processing plant activity, fuel use for plant operations was projected to remain at the current level. Electrical generation for the city was projected to grow at similar annual rates. FORECAST OF ANNUAL ENERGY REOUrTHIMEATE FOR KING COVE Fuel (bbl/yr)* 1980 1990 2000 Diesel (generation) . 11,508 12,376 12.868 aa Fuel (heating) oaLe epee sr Ste Generation (kWh/yr) City 755,900 1,231,300 1,501,000 Cannery 3,900,000 3,900,000 3,900,000 Total 4,655,900 5,131, 300 5,401,000 Peak Electric Power Requirements (kW) City 170 280 340 *One barrel equals 55 gallons. MM Chapter 3 MM ALTERNATIVE SOURCES OF ENERGY Alternative sources of electricity available to the commun- ity are identified and described in this chapter. The accur- acy of these descriptions is consistent with the amount of data available from site investigations and research on the alternatives. Continued use of centralized or decentralized diesel electric generation is included as an alternative. Near-term alternative heat energy sources are also identi- fied and characterized. Specific alternative energy supply projects that were con- sidered include: Continued central diesel electric generation Delta Creek hydropower Induction wind generation Unnamed creek hydropower Tidal power from King Cove Lagoon Peat combustion for generation Coal combustion for generation Decentralized solar-electric generation Decentralized active solar heating Heat conservation Waste heat recovery at the new city generating plant Single wire ground return electricity transmission 900000000000 General descriptions of these energy sources are provided below. SMALL HYDROELECTRIC GENERATION Hydroelectric energy is generated when flowing water spins a turbine, which drives a generator, producing electric energy. Hydroelectric generation is considered a renewable resource because the input energy source (falling water) is not de- pleted over time. Operating small-scale hydroelectric plants can also be relatively inexpensive. Use of the water is often free and hydroelectric plants cost little to operate and main- tain. Also, the cost of the electricity produced by a hydro- electric plant remains relatively constant over time. Costs rise only when inflation increases operation and maintenance costs, which constitute only a small portion of total plant costs. The major project cost is for initial construction, which can be financed and paid for in equal periodic payments that will not increase with inflation. Small hydroelectric projects can be practical in many Alaska locations. The technology has been tested and proven in Alaska and throughout the world, and the skills needed to design and build plants are readily available. Rapid and efficient construction is possible, which minimizes costs. The environmental impacts of small hydroelectric plants are usually slight and can often be easily mitigated. Most of the small hydroelectric projects considered for this study would require a small diversion dam to create a small reser- voir, a penstock to transmit the water from the reservoir to the powerhouse, and a small powerhouse. TIDAL GENERATION Tidal power is a form of hydroelectric generation. The rise and fall of ocean tides create rapidly moving incoming and outgoing water flows within narrow channels such as straits and the mouths of lagoons. The kind of tidal generation plant considered for this study would span such a channel to make use of these flows and would generate electricity from the water flow in either direction. Such plants can block the passage of boats and fish, however, so their construc-— tion and operation could present greater environmental and other problems than small, stream-based hydroelectric plants. INDUCTION WIND GENERATION Several kinds of wind-powered electric generators are com- mercially available, but they all share the same operating principle: the wind rotates the blades of a collector, which drives a generator to produce electricity. To attain the high speeds necessary for electrical generation, these wind machines must have airfoil blades similar to those of an airplane propeller. The axis of rotation for the collector can be either horizontal (like a farm windmill) or vertical (like an eggbeater). The electricity produced can either be alternating current (induction generation, which was con- sidered in this study, or synchronous generation) or direct current (which can be stored in small quantities in electric storage batteries). Because the wind is intermittent, a wind generator must be backed up by another generation source. In Alaska, this usually will be a conventional diesel engine generator. Wind generators also have a high initial cost and, because they are a relatively new source of electricity and are exposed to the elements, require more frequent maintenance than con- ventional generators. However, their environmental impact is minimal, except for some noise during operation. WASTE HEAT RECOVERY FROM CENTRAL DIESEL ENGINE GENERATORS The waste heat created by diesel engine generators can be captured and used for space heating. Ordinarily, two-thirds of the energy contained in the diesel fuel supplied to such a generator becomes waste heat that enters the environment via either the engine radiator or exhaust system. Almost all the radiated heat and about half the exhaust heat can be recovered. This means that up to half the energy content of diesel fuel can be recovered and converted into space heat for a building, if the building is within "economic proxim- ity" to the generator (that is, if the cost of capturing, transporting, and using the heat is less than the cost of space heating by other means). The medium ordinarily used to recover and transport the waste heat is water. A water-to-water heat exchanger captures heat from the engine jacket water, and an air-to-water heat exchanger captures exhaust stack heat. The heat is transferred to water that flows through a pipeline to a radiant space heating sys- tem. Another pipeline carries the used water back to the heat exchanger. One building or a building complex can be heated in this manner. These systems can require a sizable initial investment, but they are usually very reliable and make use of a source of energy that would otherwise be wasted, so their fuel costs nothing. HEAT ENERGY CONSERVATION Conservation of heat used in buildings is possible through an increase in the buildings' thermal efficiency by addition of wall, window, ceiling, and floor insulation. Three types of buildings were considered in this study: school buildings, housing built before 1964, and housng built after 1964. No conservation options were assessed for school buildings because, in general, schools are of recent construction and are equipped with adequate heat conservation devices. In newer housing, existing building components such as roofs, walls, windows, and floors provide adequate thermal effici- ency, although investigations of individual residences would probably result in specific recommendations for particular dwellings. In older housing stock, existing structural com- ponents do not provide adequate thermal efficiency. The major opportunity for heat conservation therefore lies in developing insulation programs for older housing stock. In newer housing that is presently heated with central forced air furnaces using gun-type oil burners, replacement with flame retention burners could reduce heating fuel con- sumption considerably. Overall, average conversion effici- ency of the furnaces could be improved from about 73 percent to 85 percent with the use of these fuel-efficient burners. PEAT COMBUSTION FOR ELECTRICAL GENERATION Dried peat can be used as boiler fuel for steam turbine gen- eration or piston engine generation, much the same way wood can be. The peat must be cut, gathered, dried, and com- pressed into briquettes before it can be burned. Peat may be considered a renewable energy resource, but the degree of renewability depends on the rate of use, regrowth rate, and size of the peat field dedicated as a fuel source. As with the use of wood, a considerable amount of machinery and labor is needed to harvest and process peat. The environmental costs can also be high. Harvesting can affect the land, water, and wildlife of the peat field, and peat combustion can cause air pollution. COAL COMBUSTION FOR ELECTRICAL GENERATION Coal can be burned in a boiler to produce steam, which can be used to drive a steam piston engine generator or a steam turbine generator. Coal is considered a nonrenewable resource that is relatively abundant but must usually be obtained from a distant supply source, much the same way diesel fuel must be obtained. Coal combustion technology is proven and reli- able, but the burning of coal can have a significant effect on air quality. This can be mitigated through the use of pollution control equipment. SOLAR ENERGY (ACTIVE SOLAR HEATING AND ELECTRICAL GENERATION) Much of the earth's energy is derived directly from the sun through solar radiation. This radiation can be collected and used for space heating or to produce electricity. Both systems were considered in this study. A solar space heating system typically consists of a solar collection device and a fluid to transfer heat from the col- lector to a space heating system in a building. The system can also include a means for storing the heat when the demand for space heating is low. A system to produce electric energy typically consists of an array of photovoltaic cells and a set of batteries that store the electric energy produced by the cells. The photovoltaic cells produce direct current. If alternating current is needed, as is usually the case for a house, an inverter is required. Additional electrical control systems are used to regulate the system's operation. Solar heating and photovoltaic systems can be designed for use in Alaska, but they are ordinarily quite expensive. They require a very large initial investment and often more main- tenance than alternative energy supply resources. The systems 10 also require some form of backup system that will supply a user's needs during those times when demand is greater than the solar system can supply. SINGLE WIRE GROUND RETURN ELECTRICITY TRANSMISSION Single wire ground return (SWGR) electricity transmission operates in single phase and consists of a single overhead line. The earth acts as the second or return wire. A-frame pole construction eliminates hole augering and the associated problems of pole jacketing in permafrost. In addition, local timber can be used for the poles. Single wire ground return transmission technology is relatively new, but it has been used successfully between the villages of Bethel and Napakiak, Alaska. PREFERRED SOURCES OF ELECTRICITY The alternative sources of energy identified at the beginning of this chapter were each evaluated on the basis of economic, environmental, and reliability and safety considerations, and conformance with community energy-source preferences. Out of this evaluation, summarized in Table 2, three pre- ferred or best alternatives were selected for further analysis. These are described in detail in the appendix and considered further as part of the alternative electricity supply plans described in Chapter 4. 11 Table 2 PRELIMINARY EVALUATION OF ALTERNATIVE ENERGY SOURCES FOR KING COVE Preferred Energy Sources (selected for further analysis) Continued central diesel-electric generation Delta Creek hydropower Induction wind generation Other Energy Sources (not considered further) Unnamed creek hydropower Tidal generation (King Cove Lagoon) Peat combustion for generation Coal combustion for generation Decentralized solar-electric generation Decentralized active solar heating Heat energy conservation Waste heat recovery at new city generating plant Important Characteristics No initial investment required No significant adverse environmental impacts High reliability Proven technology See note below Low operating cost and no fuel cost No significant adverse environmental impacts Important Characteristics See note below Prohibitively high initial invest- ment requirement Significant adverse environmental impacts High initial investment requirement High operating cost High fuel cost Significant adverse environmental impacts Prohibitively high initial invest- 7 ment requirement v Unproven technology Not an electricity generation source and thus not considered further Not considered further because of lack of buildings with significant heating requirements located near the city generation plant. Warehouse containing new city generation plant is not expected to require additional space heating beyond what the plant is already designed to provide. Note: Delta Creek is the lower cost hydropower project, according to Corps of Engineers data (October 1980). 12 WM Chapter 4 MM EVALUATION OF ALTERNATIVE ELECTRICITY SUPPLY PLANS This chapter identifies and evaluates alternative electricity supply plans. The plans use the preferred energy sources described in Chapter 3 to meet both peak electrical demands and annual energy requirements of the village and school. Plans were not developed to meet the relatively large elec- trical demands of the seafood processing plant. Continued use of existing diesel engine generation is considered an alternative supply plan and is identified as Plan A, Base Case. Supply plans to meet future space-heating require- ments were not developed. Alternative supply plan descriptions are contained in Table 3, and plan evaluations are summarized in Table 4. ECONOMIC EVALUATION OF ALTERNATIVE PLANS Alternative electricity supply plans were evaluated on the basis of total plan costs for installation, operation, and fuel for both the next 20 and 50 years. Total plan costs are shown in Table 4 in the columns headed "Present Value of Plan Costs." In accordance with Alaska Power Authority guidelines, the present value of plan costs is the sum of all costs (initial investment, operation and maintenance, and fuel) associated with a plan during the 20-or 50-year planning period. To obtain the present value of these costs, plan costs in their year of expected occurrence were dis- counted back to January 1981 at 3 percent per year. The rate of general inflation was assumed to be zero percent per year, but diesel fuel prices were assumed to rise at an average annual rate of 3.5 percent. This method of evaluation is fair to both the continued use of diesel generation and the alternative development of new generation sources that involve high initial costs and low operating costs, such as hydropower projects. The 3.5 per- cent annual rise in diesel fuel prices is significantly lower than the actual rise in these prices is expected to be, but the 3-percent amortization rate for high-initial-cost sources such as hydropower projects is also significantly lower than these rates are expected to be, so both types of sources receive equal treatment. ENVIRONMENTAL EVALUATION OF ALTERNATIVE PLANS Evaluations of the environmental impact(s) of alternative electricity supply plans are based on assessments of the following impacts: ° Air quality ° Water quality 13 vT Plan A (Base Case) Table 3 ALTERNATIVE ELECTRICITY SUPPLY PLANS FOR KING COVE Plan Description Continue use of central diesel generation. Two 300-kW engine generator units currently being installed (costs not included in plan costs). To meet load growth, add one 300-kW engine generator unit in 1990 ($400/kw). Replace one 300-kW unit in 1996 ($400/kW). Develop and operate Delta Creek hydropower plant. Plan and license hydropower project in 1981 and 1982; total costs approximately $50,000 for 1981 and $100,000 for 1982. Install/construct hydropower plant 1983 and 1984. Plant available in January 1985. Backup generation from existing central diesel plant. Minimum diesel backup plant operation, maintenance, and fuel cost is $10,000 per year. Excess electric energy sold to local seafood processing plant during period from 1985 to 1997. Total energy sales over period of 2.55 million kWh. Develop and operate induction wind generation facility. Maximum wind generation contribution to community electric load will be 25 percent. Plan wind generation project in 1981 and 1982; cost is approximately $50,000 per year. Install and construct wind generation facility in 1983 and 1984. Facility available in January 1985. Replace wind generation equipment in 1998 and 1999 ($386,000). Remaining generation from central diesel-electric plant. Diesel plant acquisition and replacement schedule same as Plan A. Note: All costs are based on January 1981 price levels. ST EVALUATION OF ALTERNATIVE Table 4 ELECTRICITY SUPPLY PLANS FOR KING COVE 20-Year Planning Period Present Value of Plan 50-Year Planning Period Present Value of Plan Plan Plan Description Costs ($)* Costs ($)? Energy Performance Environmental Impacts Reliability/safety A Continued central 3.04 million 7.09 million Sufficient to meet com- No major impact Highly reliable, minor (Base diesel-electric munity electric require- safety concerns Case) generation ments B Delta Creek 3.43 million (plan 5.54 million (plan Sufficient to meet com Potentially prohibitive Highly reliable, backup hydropower cost) cost) munity electric require- environmental impacts. with central diesel gen- project 0.26 million (energy 0.26 million (energy ments. Excess electric | Known spawning area for eration. Some safety sales credit) sales credit) energy available for sale coho and chum salmon. concerns regarding seis- 3.17 million (net 5.28 million (net to local seafood process- Salmon below damsite mically induced dam struc- plan cost) plan cost) ing plant could be adversely af- tural failure fected by streamflow fluctuations and silta- tion caused by project construction and opera- tion. c Induction wind 3.32 million 7.07 million Sufficient to meet com- Minor adverse environmen- Questionable reliability generation (25%) with central diesel genera- tion (75%) munity electric require- ments tal impact. Some noise emission during resource operation. Noise levels can be mitigated by re- mote location siting. resulting from variations in wind availability. Backup with central diesel generation. Minor safety concerns with remote siting. @january 1981 costs. Fish and wildlife Land use Terrestrial Community infrastructure and employment Other planned capital projects o0000 Detailed estimates of the magnitude of an impact were not possible. However, major concerns are identified and included in the evaluations. Alternative energy systems were designed to be environmentally acceptable. In those instances where additional equipment was required to make a source acceptable, the costs of such equipment were included in cost estimates. Detailed descriptions of possible environmental impacts are contained in the appendix. TECHNICAL EVALUATION OF ALTERNATIVE PLANS Alternative electricity supply plans were formulated to result in generation systems of similar reliability and safety that would be capable of meeting the complete electricity needs of the community. Detailed descriptions of each alternative's reliability and safety are contained in the appendix. CONCLUSIONS From the information in Table 4, the Delta Creek hydropower project appears to be economically feasible. When evaluated over a 50-year planing period, this project has a present- value cost of $5.54 million, which compares favorably with the cost of continued central diesel generation. Plan costs could be further reduced if excess electricity available from the project were sold to the local seafood processing plant. The Delta Creek hydropower project should be a reli- able source, with no major safety problems. It might, how- ever, create significant environmental impacts, which should be investigated further. 16 MM Appendix MM DETAILED DESCRIPTIONS OF PREFERRED ELECTRICITY SOURCES 17 Resource/Village: Continued central diesel generation/King Cove Energy Form: Electric energy General Description: Continued diesel electric generation with recently installed engine generator unit(s) Resource Location: King Cove Renewable or Nonrenewable: Nonrenewable Resource Characteristics: Diesel generation plant currently being installed con- sists of two 300-kW engine generator units. Maximum reliable electric plant output is 300 kW before additional generator units required. Energy Production: Overall estimated conversion efficiency is 12.0 kWh per gallon of fuel oil. Input Energy (fuel) Characteristics: NA Resource Reliability: Engine generator unit(s) highly reliable; questionable avail- ability of diesel fuel supply Resource Cost (January 1981 price levels): Construction and engineering ($/kW) 400 (additional units) Replacement cost ($/kW) 400 Operating and maintenance cost (¢/kWh) 2.6 Current fuel cost ($/gal.) 1.20 Maintenance Requirements: Periodic maintenance required. Minor overhaul required every 8,000 operating hours. Major overhaul required every 24,000 operating hours. Operating activity requirement is 1 hour per day for one operator/maintenance person. Resource Development Schedule: NA Environmental Impacts: No major impacts Institutional, Social, and Land-Use Considerations: No major considerations Health and Safety Impacts: No major considerations 19 Resource/Village: Hydropower plant on Delta Creek/King Cove Energy Form: Electric energy General Description: Concrete diversion dam is about 10 feet high. Penstock from the reservoir downstream to powerhouse develops about 300 feet of head. Penstock runs from the diversion dam downstream along the bench on the right side to a power- house in the vicinity of the airstrip. Resource Location: 4.7 miles upstream from mouth of Delta Creek near village airstrip Renewable or Nonrenewable: Renewable Resource Characteristics: Dam Type Concrete diversion Height (ft) 10 Operation Run-of-river Spillway Type Concrete overflow Capacity (cfs) 1,700 (500-year peak flow) Penstock Length (ft) 3,500 Diameter (in) 30 Powerhouse Type of Machine Reaction Number of Units 1 Installed Capacity (kW) 329 Transmission Facilities Type Single wire ground return Length (miles) 5.5 Energy Production: Installed capacity (kW) 329 Average annual energy (kWh) 1,419,000 Plant factor (%) 50 Dependable capacity (kW) 49 Annual energy, low-flow year (kWh) 1,135,000 Annual energy, high-flow year (kWh) 1,703,000 Input Ene: (fuel) Characteristics: Drainage area (sq. mi.) 5.0 Average annual flow (cfs) 15 Low flow (cfs) 3.5 High flow (cfs) 1,280 Total head (ft) 300 Net head (ft) 296 Maximum penstock flow (cfs) 15 Resource Reliability: The project is located on a stream with a small drainage area, and it is sized to use most of the available flow. For this reason the output of the plant is subject to natural fluctuations in runoff. The project has no storage to carry over generation capability during dry periods. Resource Cost (January 1981 ice levels): Construction and engineering ($) 3,799,000 Unit cost ($/kW) 11,547 Annual operating and maintenance ($) 44,650 Maintenance Requirements: Periodic maintenance will be required to overhaul or replace worn-out or defective parts. The frequency should be minimal because the technology for hydropower projects has been developed and proved. Hydropower proj- ects of this size can be operated with very minimal manpower and/or can be operated by remote telecommunications. Useful operating lifetime is 30 to 50 years. Resource Development Schedule: Installation/construction in 1983 and 1984, avail- able in January 1985 Environmental Impacts: Known spawning area for coho salmon and chum salmon. Salmon below damsite could be adversely affected by streamflow fluctuations and siltation caused by project construction and operation. Institutional, Social, and Land Use Considerations: Possible land-use conflicts resulting from siting of plant and transmission system. Health and Safety Impacts: No significant impacts 21 Resource/Village: Wind generation/King Cove Energy Form: Electric energy General Description: Installation and operation of horizontal axis wind induction generator(s) to provide approximately 40-kW average power output. System to consist of two wind generators rated for 40-kW maximum output each, with support towers, control equipment, and transformation and transmission facilities to integrate into existing community electric distribution system. Wind power to be backed by diesel generation to provide firm power base and for system integrity and reliability. Approximate maximum wind generation contribution to total electric system load is 25 percent. Resource Location: In favorable location with respect to wind speed and direction, as close to the central electric distribution system as practical. Renewable or Nonrenewable: Renewable Resource Characteristics: Two 40-kW-peak-output wind generation machines Energy Production: 40-kW peak output per machine, 19-kW average output per machine, 166,000-kWh-per-year electric energy output per machine, 322,000-kWh-per-year total electric energy output Input Energy (fuel) Characteristics: Average annual wind speed of approximately 17 mph. Wind speed and direction vary. Resource Reliability: Downtime for system due to lack of wind estimated at 25 to 30 percent. Maintenance activity downtime estimates at 5 percent. Resource Cost (January 1981 price levels): Construction and engineering ($) 772,000 Unit cost ($/kW) 9,650 Annual operating and maintenance ($) 14,400 Maintenance Requirements: Average operating activity requirement is one person, 1 day per month. Average maintenance activity requirement is one person, 1 week per year per machine. Annual equipment replacement cost is $5,000 per machine. Approxi- mate useful lifetime is 15 years. Resource Development Schedule: Installation in 1983 and 1984, available in January 1985. Environmental Impacts: Some noise emission during resource operation. Noise levels can be mitigated by strategic and remte location siting. Institutional, Social, and Land-Use Considerations: Possible land-use conflicts resulting from siting plant and transmission system. Health and Safety Impacts: No major impacts 23