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HomeMy WebLinkAboutNuiqsut Line Loss Analysis Report, January 18, 1991Alaska Energy Authority LIBRARY COPY 016 NUIQSUT LINE LOSS ANALYSIS REPORT PREPARED FOR ALASKA ENERGY AUTHORITY 701 East Tudor Road Anchorage, Alaska 99519-0869 by RAJ BHARGAVA ASSOCIATES 301 East Fireweed Lane Anchorage, Alaska 99503 January 18, 1991 Alaska Energy Authority Summary of Line Loss study report by AEA at Nuiqsut Pass There are large un-metered loads, such as station service, laundry and street lights. Some of the wiring in the power plant is not in compliance with the NEC code and may cause problems. The CT's associated with the Totalizing meter are not correct. Some of the meters had incorrect wiring. Most of them were rectified by the consultant during his visit. The water heater at school does not have meter and is not billed. Some of the installations have meters but are not billed. About 10 meters need recalibration or replacement. It is reported that there has been possible power theft in some cases. These meters need some sort of lock or seal. The Generators are operated in a uneconomical manner. Most of the time two generators are operated in parallel where as one generator would be sufficient to meet the load. 10.There are some over sized transformers contributing iron losses in the systen. Amit Sinha March 22, 1991. NUIQSUT TABLE OF CONTENTS Introduction Executive Summary Field Trip Procedures Nuiqsut Field Trip Report and Recommendations Appendix A - Records Collected INTRODUCTION On September 20, 1990 Raj Bhargava Associates (RBA) was issued a contract by the Alaska Energy Authority, Contract No. 2800286, Work Order No AEA-RAB-001, to perform a Line Loss Analysis in the North Slope Borough communities of Nuiqsut, Kaktovik, and Anatuvik Pass. AEA’s impetus behind this contract was to determine the causes of power losses which were reflected in the monthly reports filed by the North Slope Borough Public Utilities Department (NSBPUD) as part of the State of Alaska’s Power Cost Equalization (PCE) subsidy program, to recommend solutions to the problems discovered, and provide cost estimates of repairs. RBA was given the following specific directives: 1 Data Collection A) Collect PCE data and discuss known problems B) Coordinate with the North Slope Borough and each community 2. Field Trips A) Spot check consumer meters for accuracy B) Check for unmetered loads C) Check diesel powerhouse metering D) Check meter readers ability to read meters accurately =) Visual inspection of distribution system 3. Report A) Letter quality report in six copies with photographs, cost estimates, ACAD drawings and catalog cuts as appropriate. On October 11, 1990 this contract was amended to include an in- depth, computer-aided study of Kaktovik’s distribution system analyzing load flows, losses, voltages, and fault currents. During the weeks of November 14th and 21st, field trips were made by Thomas D. Humphrey, P.E. (RBA) to the North Slope Borough communities of Nuiqsut, Kaktovik, and Anatuvik Pass. Mr. Humphrey was accompanied by Mr. Frank Foote NSBPUD during all of the investigations. This document is RBA’s final report. The in-depth study of Kaktovik is attached as a separately bound appendix to this report. LOAD ANALYSIS REPORT JOB NO. AP-05 Page 2 EXECUTIVE SUMMARY All of the line losses in these communities are identifiable and can be attributed to the following causes: 1. Unmetered loads The most significant unmetered loads were the NSB powerhouse station power, the NSB laundry/washateria, and the NSB street lights. 2. Unrecorded meters This category included NSB owned and operated facilities e.g. runway lights in one case. Often where buildings had been vacated and later reoccupied, the meter reading sheets had not been caught up with the current occupancy status. 3. Faulty meter wiring. Faulty wiring was suspected at locations which utilized current and/or potential transformers. All of these locations were checked. Problems encountered included reversed polarities, wiring for the wrong form, incorrect application of multiplying factor, and missing circuit closing contacts. For the most part all faulty meter wiring was corrected in the field during our investigations. 4. Normal system losses. In several instances transformers are considerably oversized. Reduction and/or elimination would result in savings. Long and/or undersized secondary runs also contribute to the overall systems losses. Fuel efficiency could be improved by utilizing a more precise schedule for maintaining units on line. Operator logs reveal that many times two units are kept on line when one unit would suffice. LOAD ANALYSIS REPORT JOB NO. AP-05 Page 3 FIELD TRIP PROCEDURES: a Talk to the meter reader. A. Review record keeping and collect representative data B. Determine meter reading abilities C. Use records to indicate other loads that may have been missed and test if instrument class. D. Analyze records to find meters running backwards or misread. Check the wiring and test the meters at each of the following facilities: A. Powerhouse - Bus totalizing Station Laundry | Water/ sewage & misc. or other powerhouse load School USDW (Combined School District Warehouse) 4 meters USDW - Warm Storage/Equipment Shop Other Commercial Customers without self contained meters. mo oO Meter test procedure (3 phase loads) A. Record the meter CT & PT nameplates. B. Verify the wiring for specific Form of meter being used. -Check for unmetered loads Cc. Measure the voltage and current. -Measurements were taken using a Fluke 8060 RMS meter and Fluke 80:400 AC Coupler. D. Time a specific multiple of disk revolutions in seconds. E Compute the expected Kwh based on measured voltage & current, and compare against Kwh based on disk revolution times. Fe Sketch one-line and note any code violations. Spot check all other commercial loads, street lights, verify residential loads, unrecorded loads, and meters which appear from the records to be working wrong. Inspect fuel meter and collect meter reading data. Visually inspect all of the outside plant and update the system as-builts. LOAD ANALYSIS REPORT JOB NO. AP-05 Page 4 NUIQSUT Field Trip Report Inspections made by Tom Humphrey (RBA) Frank Foote (NSB) Dave Kippi (NSB) November 20 & 21, 1990 NUIQSUT NUISQUT TABLE OF CONTENTS Executive Summary Kilowatt-hour Reconciation Fuel Consumption & Efficiency Field Investigation Reports Appendices Page 2 EXECUTIVE SUMMARY Nuiqsut was the first village inspected by our team on this assignment. Our strategy was to inspect and test all of the major loads in the community. After this test we then thought to verify the total consumption with a test period reconciliation - reconciled against both totalizing Kwh meter and fuel consumption. Our specific recommendations are listed on a case by case basis in the field investigation part of this section. Our test period load reconciliation indicating that with the conrrections made substantially all of the load will be accounted for. When based on total Kwhrs generated the fuel efficiency of this community powerplant is a respectful 12.9 Kwhrs/gal. NUIQSUT Page 3 KILOWATT-HOUR RECONCILIATION Summary of Unmetered and/or Unrecorded Conditions Estimated by Month KwH for 10/90 NSB - Power plant 17218 Laundry 11837 Water/Sewer 3766 USDW - Panel A 1680 Panel B 1760 Panel C 680 Panel D 9680 Water Heater 2000 USDW - Warm Storage 3597 NSB - Runway Lights 6480 NSB - Street Lights 6552 Total 65250 Kwh Residential Metered Load 34575 Commercial Metered Load 66871 Unmetered Load (estimated) 65250 166696 5% line losses (est) 8335 Total 175031 Kwh Totalizing-KwH meter 9/31 1444 (10/1 reading of 1464 less 20) 10/31 2852 608 x 288 = 175104 Kw hrs. NUIQSUT Page 4 FUEL CONSUMPTION & EFFICIENCY Fuel Consumption: 13598.6 gal. Kw hr./gal. = 12.9 Adding the unmetered load and comparing the totals to the totalizing Kwh meter and the fuel consumption correlates very closely and indicates that corrections made as estimated herein will now account for all of the kwhrs being used. NUIQSUT Page 5 FIELD INVESTIGATION REPORTS We adopted the following procedure while checking meters in this community: 1. Record the meter plus CT & PT nameplates. 2: Verify the wiring A. Check for unmetered loads 3. Measure the voltage and current. A. Measurements were taken. 4. Time the revolution of the dish using a Fluke 8060 RMS meter and Fluke 80:400 AC Coupler. 5; Compute the expected time based on measured voltage & current, and compare against actual times. 6. Talk to the meter reader and others about problems they may know about 6A. Collect representative data. 7. Update system as-builts. We checked the following loads: 1. School 2: Powerhouse - Bus totalizing Station Laundry Water reservoir & misc. 3. USDW (School District Warehouse) 4 meters 4. USDW - Warm Storage/Equip. Shop 5. REIL Office AKA Terminal Bidg. Runway lights. 6. Street lights Individual reports in each of these loads are given on the following pages. NUIQSUT Page 6 Vs TRAPPER SCHOOL METER This school is fed directly from the power house from a 250 A 3-pole circuit breaker located in the main 480V bus. The Section is (3) 250 MCM copper which runs about 150 feet in underground conduit to a 225 KVA dry type transformer located in a wooden enclosure on a platform behind the school. The 120/208V 3-phase 4 W outside feeder is 5010MCM copper. One is run underground in conduit about 100 feet to the school’s main switch generator. The school’s meter is located next to the main switch generator. CT's are located in the switch gear. Summary meter data: Summary CT data: Sangamo Form 6S Abbott Machine Corporation SN#49187976 800/5 Ratio 20CL 120V 4W Y 60HZ Cat. No. 100-801 50-400 HZ 1.8Kh 25TA 600V 10 Kv BIL 11.1 9 Rr Type S55, 2 station A comparison of the meter wiring indicated that both the B & C phase current taps were revised and the C phase voltage tap was connected to B. This would not have affected the operation but we rewired it to match the diagram for four 6S precisely. Note that there were no circuit closing devices so CT’s were jumpered before we rewired the meter. Data Measurements - Meter reading 1849 Vas 205 I, 161 Vac 206 \, 188 Vac 206 I, 181 1 Disk Rotation = 17 seconds Power Factor estimated at 0.95 Calculations: Computed Kw = 1.73 xP (by 1 + E measurements) 1000 me 178 x 206 x 1.73 x 0.95 = 60.3 Kw 10.0 Computed Kw = 3600 x rev x PKh, where PKh = Kh x CTR x PTR from Disk Rev t (sec) x 1000 NUIQSUT Page 7 x 1x 1.8 x 160 x 1 60.9 Kw 17 x 1000 In addition to the totalizing meter, there is a Dranetz Power Line Distribution Analyzer Series 606 was installed in the switch gear which periodically records average single phase voltage, frequency, and sag, surge events. RECOMMENDATIONS: 1. Install a circuit closing meter socket or at least a warning sign to prevent CT's from being burned out accidentally. 2. Install meter with KW dial. 3. Move CT’s to line side of step-down transformer. Trnasformer losses should be billed in the School Districts rates. 4. Reduce the outside step-down transformer, e.g. from 225 Kva to 100 Kva to reduce transformer losses. NUIQSUT Page 8 2. POWERHOUSE There are five generators, two each 225 Kw Caterpillar 3406B (Units 1 & 2); two each 210 KW Caterpillar (Units 4 & 5); and one 155 KW Cat 3306 (Unit 3). Total generation available is 1.025 MW. Units 1 and 2 were both on-line at the time of our investigation. The generator switchgear allowed for parallel operation of any or all of the generators. Each generator cubicle had a full complement of V, A, KW meters. The main bus was rated at 1000 A, 480V. On the generator switchgear are two Kw-hour meters. The left hand GE meter was supposed to be recording the total KW hours generated and the right hand Sangamo meter was supposed to be recording the station power used. The operators have been recording both these meters on their daily logs at 8 AM each day. The operators also log all of the individual generator & engine parameters on an hourly basis. Meter Data: GE VM-65-S Sangamo Form 65 Form 65 Crt #700X25G2 Rr = 1111/9 SN 78773423 SN 49390816 TA 2.5 TA 2.5 Kh 1.8 Kh 1.8 10 CL 20 CL 120V, 4WY 120V, 4WY, 60 HZ 2 station 2 station In addition to these meters was a Dranetz Series 808 - Electric Power/Demand Analyzer which gave status reports on demand and daily totals automatically at 12 midnight each day. Pais: Microm Industries B2050 x 15 - PF 288V 600/5 Pnl 120V Sec Wired Y-Y PTR = 2.4 CT’s Due to inaccessibility, we could not see the nameplates on the CT’s. Assumed to be 600/5 based on 288 multiplier in use (CTR = 120). Investigation showed that the Sangamo meter was wired to the GE meter and had mistakes in the wiring, e.g. the common neutral off the CT’s was tied to the C phase voltage terminal. Looking at the logs, this meter ran erratically. Looking at the wiring, it appears that it was just identified as a check on the GE meter. Frank proceeded to remove the Sangamo from the panel and also rewired the GE meter. After rewiring, the following data was recorded from the Dranetz: 291.3 kW, .89 PF and a disk time of 6 seconds. NUIQSUT Page 9 Kw = 3600 x 1x 1.8 x 2.4 x 120 6 x 100 311 Kw A second test was run for 10 revolutions. Total 87 seconds. The load generated from 275 Kw to 287 Kw. Observed on the Dranetz. Kw = 3600x10x 1.8 x 2.4 x 120 87 x 100 214 Kw These readings were 20% lower and we felt the CT ratio must be 800/5 which would have yielded 284 Kw or right on. However, based on additional equipment, conditions, and the fact that the 6 second test read high, I feel that the CT’s are probably 600/5 and our 10 revolutions test was somehow in error. The main distribution panel has 7 circuit breakers in use; all of which are essentially unmetered, although the four main feeders have ammeters on each ammeter. C/B1 600/3 West Distribution System Feeder % 236 \ In 242\ Ip 89 > From Fluke I, 100 > From Panel Meter Ic 172/ Io 165 / ; C/B2 600/3 East Distribution System Feeder ly 137 k 140 Ip 155 (erratic) Ip 235 le 127 Ic 140 C/B3 250/3 School Feeder I, 54.1 _ 534 Ip 60.5 Ip 58 Ic 60.5 Ic 54 C/B4 100/3 Generator Bldg. - Station Power im 32.1 i oe Is 32.0 _, 3» le 345 ne C/B5 125/3 Laundry I, 20.2 i 21.0 ie 27.5 NUIQSUT Page 10 C/B6 C/B7 50/3 OEFH 1 a 8.5 ly 14.9 Ic 10.6 50/3 OEH 2 ly 3.0 Ip 2.8 i. 3.8 Measurements were taken at 18:53 on 11/20/90 NUIQSUT RECOMMENDATION: Install meters to all unmetered feeders. Organize loads into these groups: iis Station power 2s Feeder East 3. Feeder West 4. School Ss Laundry 6. Water & Sewer Plant The West feeder has a single 250 MCM copper connector on‘a 600A breaker with an ampacity rating of 255A and is a violation of NEC Article 240-3. The overhead drop portion of the West feeder rubs against the vent hood near its point of attachment to the generator building. This is a violation of NEC Article 230-9 and in combination with the other problem (3) noted above, could result in catastrophic failure to the feeder if not fixed. There is a good possibility that the relays and circuit breakers have never been tested or calibrated. This should be done at least every two years. Verify that the bus totaling CT’s are 600/5. Page 11 3. USDW SCHOOL WAREHOUSE This building has a 3-phase, 1-wire, 208 volt service. Switchgear and circuits are located on the mezzanine storage level. Meters are located just inside the east entrance. The switchgear has 5 mains, one of which is unmetered and serves a 27 Kw electric water heater. The other four are individually metered and are identified as Panels A, B, C & D. Panel A - Public Works Shop, Panel B - School District Shop, Panel C - Water & Sewer, Panel D - Headbolts. Meters All Y CT’s all Y Sangamo Type SL4S GE JAK-0 Rr = 111 1/9 A 200/5 20 CL B 200/5 120V, 4 WY C 200/5 TA = 2.5 D 400/5 FL = 1.8 Form 9S 3 station The wiring checked out correctly with the exception of having the Z terminal grounded when it wasn’t supposed to be. We removed this ground. rial er: Current Reading A 712 80169923 B 401 80169926 Cc 436 80169922 D 2252 80169925 DATA Panel A___Pane! B___— Panel C__ Pane! D Vag = 1995 |, 13 10.30 .06 57.8 Vac = 203 I, 10.13 16.80 8.90 73.3 Vac = 207 |, 24.80 0.00 5.50 45.6 Vavg 201.2 I avg 11.68 9.03 4.82 58.9 1 Disk Rev = 60.0 90.0 104.0 28.4 sec. The water heater feeder was pulling about 0.1 A indicating it wasn’t on. Nameplate data: State Mod #CMSF10, S/N 3407, 27 Kw at 208V, 36 Kw at 480V. NUIQSUT Page 12 1A =Be —c_ DE Kw Measured 3659 2829 1510 18451 Kw Timed 4320 2880 2492 18253 RECOMMENDATIONS: Install meter for water heater feeder. Also needs ground on conduit bushing in switchgear. Start billing for these meters and including on monthly reports. Buildings are about 1 year old and the meters have been read - just don’t appear to be put on reports yet. NUIQSUT Page 13 4. USDW (HEAVY EQUIPMENT SHOP) Meter Data: SANGAMO Type S55 Form 14S CL 20 120V 4WY 60 HZ SN 76354995 Kh = 21.6 Rr = 9 7/27 TA = 30 Current Reading 20308 DATA Va 117 Ay 18.2 PF Estimated @ 0.9 Vp 121 Ag 19.1 vc 116 Ac 5.4 an 118 ti ng 14.2 2 disk revolutions = 33.14 SEL Kw (calculation) = 4530 Kw (disk rev) = 4684 RECOMMENDATION ne Start billing for this meter and adding it to the monthly reports. NUIQSUT Page 14 Ds NSB R.E.L.I. (Terminal Building) This building has 2 meters mounted on the outside. One meter is supposed to record the building load. The other is for the runway lights. Airfield lighting meter AKA Panel ’A’ TERMINAL BLDG: RUNWAY LIGHTING CT’s 400/5 GE V-64-S GE Catalog #705610G11 Form 16S Form 6S SN #76407374 SN #76650668 200 CL Self-contained meter 2066, 240V, 4 WY Rr 9 7/27 TA 2.5, Kh = 3.6 TA 30 Rr - 55 5/9; Current reading: 2241 Kh 21.6 Current Reading: 65248 Wiring checked out all right. However, meter indicating lights were not on and test calculation indicated a 40% low reading. TEST DATA Vap 203.2 I, 5.4 (Note unbalance) Vac 199.7 Ip 39.4 Vac 199.3 Ic 45.7 T sec rev. = 2 minutes, 59 seconds = 179 seconds Kw (calc) = 200.7 x 30.2 x 1.73 x .9 = 9437 W Kw (rev) = 3600x1x3.6x80 = 5792 W 179 RECOMMENDATION ne Both meters should be replaced with tested and calibrated meters. 2: At present, only the building meter is being read and billed. The runway lights meter should be read every month, billed, and added to the report. NUIQSUT Page 15 STREET LIGHTS We counted 91 street lights. The meter reader's notes indicate 95. They are all newly replaced. 150 W HPS. NSB also recently installed 1 metered street light. (2 weeks ago). RECOMMENDATION a Start reading street light meter on a regular basis and use for monthly reports. 2: Spot check and record burnouts. NUIQSUT Page 16 Te OTHER FINDINGS ie NUIQSUT Meters are read on the third Monday of each month. PLE reports are based on the billing period which is dated at the end of each month. Fuel and Power Station measurements are read and recorded daily and reported on actual calendar months. There was some discussion about possible theft of power due to unmetered situations (bypassed) and meters installed backwards for part of a month. NSB should replace and install lockable-type meters at any suspect location. Reviewing the monthly meter readings for 10/15/90, the following meters should be checked: A. AHNVPKANA, Johnny Acct 330505 630000646 Meter reported upside down. B. HOPSON, Steve, Jr. Acct 330522 Meter 57323505 C. AHKIVIAWA, Archie Meter 63060646 Serial Number indicates multiples may be 1 not 10. Verify. D. KAZMIENCZOK, Mike Meter 63000593 Same as Item C. E. KOVALSKY, Richard Meter 57779069 Meter runs backwards. F. NUIQSUT, Others’ Club/Health Board. Should be prorated i.e. split not doubled. G. NSB CIP (White Trailer) Meter 63000745 Running backwards. Page 17 USDW CT CABINET NUIQSUT - USDW METERS NUIQSUT Page 18 NUIQSUT - LAUNDRY NUIQSUT Page 19 NUIQSUT - SCHOOL METER & SWITCHBOARD NUIQSUT Page 20 NUIQSUT - POWERPLANT NUIQSUT Page 21 EAST FEEDER AT POWER PLANT NUIQSUT - EAST & WEST FEEDERS AT POWERPLANT NUIQSUT Page 22 USDW & HVMF SERVICE NUIQSUT - REIL & AIRPORT BUILDING NUIQSUT Page 23 NUIQSUT - SCHOOL 480-120/208 TRANSFORMER NUIQSUT Page 24 Appendix A - Samples of Records collected for Nuiqsut Index 1. Operator’s Daily Log Sheets, one or two months typical from each community. 2. NSB’s Log of monthly average & peak data 1989, 1990 from NSB 3. NSB’s Log of monthly KWH FY 89/90 from NSB 4. NSB’s Tariff regulations from NSB 5. Monthly meter reading report one or two months typical from each community. 6. PCE Reports, three or four months typical form each community from AEA 7. Rural Utility Powerhouse Inventory 8. AEA Monthly PCE statistics report 7/89 to 4/90 9. Assorted Utility Meter Records 10. Dranetz printout approximately 30 days ending 10/27/90 11. Drawings: 3 sheets E1-E6, Lot S-1 "Electrical Distribution System Modifications:" by Coffman Engineers, 1/2/85 NUIQSUT Page 25 Appendix A- continued REFERENCES 1. "Economical Design of Primary Line for Rural Distribution System" REA 60-9 2. "Electrical Distribution Systems - Engineering Manual" EBASCO/Electrical World, Vol. 1,2,3 3. "Distribution Primary Analysis Systems" Software by HDR Engineering 4. GE "Guide for Installing GE Watt-hour meters," GET-2669J NUIQSUT Page 26