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HomeMy WebLinkAboutNikolai lighting Project Status Reports, Trip Reports, & Field Notes 1988Nikolai Lighting Project Annual Capital Project Status Report (this paragraph is to be included in the general description for the Nikolai generation and distribution system improvements) Energy improvements in Nikolai also included conversion of incandescent lighting in homes to low-energy fluorescent lighting. This work was completed in 1987 and followed by a 12 month monitoring period to document energy savings. Results showed an overall drop of about 13% in residential energy use in the year after the improved lighting was installed. This reduction in load, along with larger, commercial load reductions, allowed the community to begin using a less expensive, smaller generator. Assistance audit of Nikolai's generation and distribution system. The photographs on the following pages illustrate many problems Nikolai residents experienced with the old system. Energy improve- ments on Nikolai's engine-generators, distribution system, and commercial buildings were completed during the year the lighting study was underway. The sections below describe these activities. (1) Generator Improvements Before electrical improvement projects were initiated in 1987, two of the City's generators had burned out because fuse protection was lacking on old-style transformers. The remain- ing 85 KW engine generator unit was burning about 26,430 gallons of fuel annually. By reducing end-use loads and reconfiguring phase balances in the system, the City was able to run the entire system on smaller generators. New generator in existing powerhouse module. 3727/909/31 - 27 - A 75 KW and a 70 KW unit were purchased to replace the two burned out generators. These units are run alternatively in place of the 85 KW engine-generator, resulting in an estimated annual fuel savings of 3,200 gallons. At $1.56/gallon, estimated annual dollar savings for the generator replacements is about $5,000. Labor and materials costs for generator replacements are estimated at about $8,000. Simple payback based on these figures is about a year and a half. In addition to the generator replacements, about $8,000 in improvements to the three power houses were also made. Improvements included replacing power house roofs, installing fire-treated plywood on walls, and putting new mufflers and battery charging systems on all three generators. New doors and lighting systems (including emergency lighting) were also added. An electronic governor was installed on the new 70 KW generator, and overload protection on both the 70 KW and 75 KW units. Vent systems were also installed in the power houses. (2) Reconfiguration of Resistance Loads One of the main problems with Nikolai's overall system design was the high number of resistance loads. Generator overload- ing was caused by both phase imbalances and large loads capable of coming on line simultaneously. In the Lodge/Duplex, a commercial building, three electric hot water heaters (5 kilowatts each) were replaced with one oil-fired hot water heater. Two of the electric hot water heater tanks were removed, and a third was kept for storing water heated by the two woodstoves in the Lodge. The new oil-fired hot water heater acts as a backup unit to the 3727/909/32 - 28 - wood-fired/storage unit. The two systems were piped in series, with the oil heater set to kick in if wood-fired hot water drops below 140 degrees Farenheit. Two small space heaters (3 kilowatts combined) were replaced with one non-electric unit heater connected to the circulating hot water system. A heat tape with approximately 1 kilowatt capacity was also disconnected at the Lodge. The main reason for these modifications was to avoid problems with a theoretical peak load of 19 kilowatts on one phase of Nikolai's system from the Lodge/Duplex alone. Nikolai's electrical system is capable of providing 85 kilowatts of capacity when the largest generator is used or 60 kilowatts when either of the two smaller generators is used. One phase is capable of supplying slightly more than one-third of the 60 kilowatt generator's capacity. Consequently, the Lodge's heavy load created problems for the entire system. One-phase and three-phase service connections to washeteria. 3727/909/33 - 29 - The City Hall washeteria had two single-phase, 5-kilowatt dryers and two, three-phase washing machines. The 10 kilowatt dryer load was split among the three phases coming into the building. Five kilowatts was connected to one phase and 2.5 kilowatts to each of the two remaining phases. Nikolai's City Hall also had two service drops, one of which was eliminated due to safety problems. The redistribution of this load also helped to balance the system, allowing the utility to use the smallest of the three generators without fear of overloading a single phase. No direct electrical savings can be attributed to the phase balancing activities at City Hall, although there will be some indirect savings from the utility's ability to operate a smaller generator for the same electrical load. Estimated labor cost for the work at City Hall was approximately $100. Improvements to the Lodge/Duplex cost approximately $2,500 in materials and $1,500 in labor. Since March 1988, when im- provements were completed, kilowatt hour meter readings for the Main Lodge showed savings as follows: Month Year Difference % Change 1987 1988 March 2,080 1,416 - 664 -31.9 April 1,494 253 -1,241 -83.1 May 1,247 231 -1,016 -81.5 June 1,327 115 -1,212 -91.3 July 1,114 122 - 992 -89.0 August 418 181 - 237 -56.7 Totals 7,680 2,318 -5 ,362 -69.8 Compared to the same six months for the previous year, there has been a reduction of 5,362 kilowatt hours or 69.8%. 3727/909/34 - 30 - Monthly kilowatt hour savings should improve during the winter, as higher electric heating costs are avoided. A rough payback for Lodge/Duplex improvements can be calculat- ed using an annual 10,000 KWH estimated savings. Divided by a system efficiency of 10 KWH/gallon, about 1,000 gallons of fuel could be saved. At $1.56/gallon, this results in an annual savings of $1,560. Actual savings may be less due to lower fuel prices. (3) Distribution System Electrical improvements in Nikolai included complete replace- ment of the distribution system. The old 480 volt, three- phase system had low clearances, distribution wiring suspended from trees, and transformers open and accessible to children. Safety problems were considered severe, as some transformers were as low as four feet off the ground. Additionally, project staff discovered the use of overhead cable in an underground application, a situation posing extreme safety problems. Overhead line was buried under the airport runway and extended to service customers in a separate part of the community. As mentioned above, the old distribution system included dry-style transformers with no fuses, which resulted in burnout of two generators. With all of these problems, the system was extremely inefficient, with line losses estimated as high as 25%. 3727/909/35 - 31 - Interior type transformers, exterior mounted 3 and 6 feet above ground. Uninsul- ated splices accessible behind cover. 480 volt. In 1987 a new 12,470 volt, three-phase system was installed throughout the entire community. Design and construction was based on Rural Electrification Association (REA) standards. Most poles were replaced and new poles were added to bring the system up to REA standards. A 7200 volt, underground, single-phase line was run to the north side of the runway to serve customers located away from the central part of the community. The project also included upgrading all service drops. 3727/909/36 - 32 - Replacement cost of the entire distribution system was approx- imately $123,000. A portion of these funds was paid to the City for local work crew salaries, thus contributing to the local economy. The primary reason for replacement of the distribution system was safety, but fuel savings can also result from reduced line losses. These savings can be estimated by taking an annual net generation estimate of 250,000 KWH per year and figuring 25% line losses at 62,500 KWH/year. Under the improved distribution system, a net generation of 250,000 KWH per year at 5% line losses yields 12,500 KWH/year, resulting in a reduced generation requirement of about 50,000 KWH/year. Close-up view of 480 volt duplex line mounted in tripod approximately 8 feet above ground. 3727/909/37 - 33 - VII. By dividing this 50,000 KWH by a generation efficiency of 10 KWH per gallon, an estimated annual fuel savings of about 5,000 gallons may be realized from improvement to the distri- bution system. Using the average cost of $1.56/gallon for oil, this results in an estimated dollar savings of $7,800. With estimated project costs at $123,000 and estimated first year savings of $7,800, a simple payback for this project is just under 16 years. The older system also had high operating costs because the larger, 85 KW generator was needed to handle the high load requirement caused by extreme line losses. Dropping line losses by an estimated 20% and reducing commercial load enabled the City to use a newer, smaller generator. All of these electrical system improvements resulted in increased reliability, fuel efficiency, lower operating costs and improved safety. The original appropriation for this project was motivated by safety concerns, but system modifi- cations resulted in energy savings as well. It should be noted that combined energy savings for generator, distribution system, and end-use improvements may be less than the savings that is calculated for each of the projects individually. Heating System Improvements Waste Heat Project In 1987 the City of Nikolai completed work on an existing mainte- nance building. Originally constructed in 1985, the maintenance shop did not have a heating system. The original building consists of a two-story, 40' x 40' shop area and two 20' x 40' maintenance bays. The maintenance bays are used for storage and repair of 3727/909/38 - 34 - heavy equipment such as the City's fire truck and earth moving machinery. In 1988 a waste heat system was designed and installed for the building. Adjacent to the maintenance building, there are four separate generator buildings; three belonging to the City and one to the school. The cooling systems for the three City-owned generators were tied together with a heat exchanger system that transfers heat from the generators' jacket water to a circulating system in the maintenance building. Waste heat utilidor from generator house to maintenance building. 3727/909/39 - 35 - Heating lines from the power house were run about 20 feet to the maintenance building through a 12" x 12" fully-insulated utilidor. Heat is distributed through six unit heaters suspended throughout the building. A pump circulates anti-freeze through the distri- bution system. Separate unit heaters provide heat to the four power houses. Since this is a newly-installed system and there are no heating records for earlier years, fuel use was estimated to be about 4,700 gallons per year. Using the average fuel cost of $1.56 established for the lighting project, annual first-year costs for heating the building would be about $7,332 if this level of fuel consumption actually takes place. Estimated simple payback for the waste heat project, based on a $19,000 project cost, is a little over two and one-half years. This figure will vary depending on the actual avoided heating fuel costs, which will be available after the first heating season. Maintenance building. 3727/909/40 - 36 - Dates: Purpose: Results: Costs: NIKOLAI RESIDENTIAL LIGHTING PROJECT July 1987-June 1988 To measure energy savings from replacing incandescent with low-energy fluorescent Light bulbs in community residences. A 12.7% reduction in electrical use by households over the one year period. An estimated first year fuel savings of 738 gallons An estimated cost savings of $1,151 First-year payback for project is 1.95 years. Savings are expected to continue for an additional 17 months before bulbs scheduled for replacement Materials and shipping costs were $2,246. Project management labor was donated by City of Nikolai. Nikolai Lighting Project Executive Summary The Nikolai Lighting Demonstration project was conducted from July 1987-June 1988. Its purpose was to measure energy savings from replac- ing incandescent with low-energy fluorescent lighting in 36 community residences. The project resulted in a 12.7% reduction in electrical use and an estimated savings of $1,151 in avoided oi] costs for the communi- ty over the one year period. Other project objectives included the following: eto determine the impact of changes in kilowatt hour sales on the utility's annual fuel and operating costs, *to develop a profile of how homes use electricity; and eto identify installation and operating problems with low-energy fluorescent bulbs. While the lighting project was underway, several other energy improve- ments were completed in Nikolai. These included replacing the City's generator and electrical distribution lines, installing a waste heat system, phase balancing the distribution system, and reducing the electrical requirements of the City's Lodge/Duplex building. A section of this report provides details on these projects, and empha- sizes the importance of evaluating all parts of the utility's system to determine the best type of improvement. These combined activities should result in significant fuel savings for Nikolai over the next several years. Using the simple payback method, the projects' costs and benefits are described in the table on the next page. 5258/954(1) Nikolai Energy Improvements Cost/Payback Estimates Project Description Cost Estimated Estimated Payback ($) Fuel Savings Ist Year (Years) ** (Gallons )* Savings($)* Generator Replacement 8 ,000 3,200 5,000 1.50 Lighting Project 2,246 738 1,151 1.95 Lodge/Duplex 4,000 1,000 1,560 2.56 Load Reductions Waste Heat Retrofit 19,000 4,700 7 332 2.59 Distribution System 123,000 5 ,000 7,800 16.00 * Savings cannot be added. Multiple improvements affect savings calculations for the total system. ** Payback Years are based on assumptions such as fuel cost, system efficiency and estimated savings that may vary in practice. Without sub-metering households, electricity savings can only be es- timated. Estimates can be improved, however, by identifying how elec- tricity is used in the home. A preliminary household survey was conducted to accomplish this objec- tive. The survey identified the number and type of appliances in each home, and the lighting wattages before and after the low-energy fluores- cent bulbs were installed. This information was used to estimate the percentage of electricity used by light bulbs in community homes. Monthly energy use for all residences began to decline three months after the bulbs were installed. Changes in appliance use were con- sidered negligible, and the decline was attributed wholly to the change in lighting. Monthly kilowatt hour use is described in Table 1 of the report. Savings were calculated by comparing electrical use for each household 12 months before and after energy-efficient lighting was installed. A follow-up consumer survey was conducted 12 months after low-energy fluorescent lighting was in place. This survey evaluates consumer 5258/954(2) response to the lighting project. It provides information on durabil- ity, lighting quality and costs of low-energy fluorescent bulbs. The results of the two surveys are discussed in the report. The report evaluates the affect of declining fuel costs on Nikolai's Power Cost Equalization (PCE) rate and consumer tariff. During the two year study, Nikolai's PCE rate dropped from 41.8 cents per kilowatt hour to 21.0 cents. The community's tariff dropped from 60 cents per kilowatt hour to 50 cents. The final portion of the report discusses the potential impact of energy projects on utility cash flow and tariffs. This section presents different points to consider when planning an energy project. Both regulated and non-regulated utilities are discussed in this section. The report stresses the importance of prioritizing energy projects to achieve the best return on investment. Improvements in generator efficiency can have positive, short-term benefits in reducing utility fuel use and costs. In the case of Nikolai, energy efficiency improve- ments to the City's Lodge/Duplex building had a larger kilowatt hour savings than the residential lighting program. Each rural electrical system is unique, and should be considered as a whole when prioritizing energy projects. The projects in Nikolai demonstrate the effectiveness of looking at supply and end-use as a dynamic system. A combination of energy improvements keeps the whole system sized to the community's needs, and provides effective long-term savings for rural consumers. 5258/954(3) Table 1 Nikolai Lighting Project Changes in Residential Kilowatt Hour Use Month FY87 Usage FY88 Usage Difference Difference (KWH) (KWH) (KWH) (%) July 3,638 4,162 + 984 +14.4 August 4,090 3,524 - 566 -13.8 September 3,376 3,858 + 482 +14,3 October 4,740 3,756 - 984 -20.8 November 4,370 3,783 - 587 -13.4 December 5,763 4,421 -1,342 -23.3 January 4,855 3,538 -1,317 -27.1 February 3,748 3,295 - 453 -12.1 March 4,212 3,492 - 720 -17.1 April 3,706 3,194 - 512 -13.8 May 3,901 3,701 - 200 - 5.1 June 4,205 3,478 - 727 -17.3 Totals 50,604 44,202 -6,402 -12.7 3727/909/19 - 15 - KWH USE 6000 5900 0000 4500 4000 3900 3000 Nikolai Lighting Project: Changes in Residential KWH Use \A “ \ L o | == Cd , JUL AUG SEP OCr NOV DEC JAN FEB MAR APR = MAY JUN @ FY87 Ct FY88 Nikolai Lighting Project Monthly KWH Use Lodge/Duplex Building Month Year Difference % Change 1987 1988 March 2,080 1,416 - 664 -31.9 April 1,494 253 -1,241 -83.1 May 1,247 231 -1,016 -81.5 June 1,327 115 -1,212 -91.3 July 1,114 122 - 992 -89.0 August 418 181 - 237 -56.7 September 538 198 | - 340 -63.2% October 413 424 11 2.7% November 675 498 - 177 -26.2% December 1786 562 -1,224 -68.5% Totals 11,092 4,000 -7,092 -63.9% 5257/909/2 Nikolai Lighting Project: Monthly KWH use for Lodge/Duplex Building 2500 + 2000 <— . 1500 + 5 L = a 1987 KWH USE Oo 1988 1000 + 500 + i —— IO 0 + + + + + + t + 1 MAR so APR”s—“‘iwMAY.S=~Ss*«WUNSs«SULs— sAUGS—“(i«s*sé«SEP=CS*~*«!SC*«‘iNGSCS:*«éOMC