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Home My WebLink AboutEPS BESS ANALYSIS - NEA BESS Scenario Analysisper' Electric Power Systems, Inc. 3305 Arctic Blvd Suite 201 ■ Anchorage, Alaska 99503 ■ Tel: (907) 522-1953 December 1, 2022 Subject: NEA BESS Scenario Analysis ANALYSIS OVERVIEW The objective of this analysis is to quantify the potential benefits of using a Battery Energy Storage System (BESS) to supplant the use of reserve spin. The specific quantities to be developed by this analysis is the reduction in genset run -hour, reduction in fuel usage, and change in heat recovery capability between two utility operating scenarios: the existing scenario where gensets are staged on with one full genset of reserve spin, and a future scenario where there is no reserve spin (due to the use of a future BESS). ANALYSIS INPUTS The inputs to this analysis are: • CAT genset performance data • Approximately 560 days of electronically logged power delivered to distribution. The genset performance data for a CAT 3512B and a 3516 genset were used: GENSET '3E LOAD EKW FUEL FUEL JW REJ JW REJ GPH GPH{KW BTUNIN MBH 3512B 1003E 1,015 69.6 0.069 28.321 1,699 3512E 90% 914 62.2 0.068 25,976 1.553 3512E 809E 812 55.3 0.068 23.544 1,413 3512B 759E 761 52 0.068 22.464 1,349 3512E 70% 710 49.8 0.069 21,326 1,290 3512E 609E 609 42.8 0.070 19.165 1,150 3512B 509E 508 37 0.073 17.061 1,024 3512E 40% 406 31.3 0.077 14,957 997 3512B 309E 305 25.6 0.084 12.739 764 3512B 259E 254 22.6 0.089 11,545 693 3512E 20% 203 19.7 0.097 10,293 61s 3512B 109E 102 13.4 0.132 7.564 454 3516 1003E 1,135 75.53 0.067 34.691 2,091 3515 903E 1,022 58 0.067 31,109 1,966 3516 809E 908 60,89 0.067 27.582 1,655 3516 753E 95' 57.35 0.067 25.976 1,553 3515 703E 795 53.81 0.068 24,170 1,450 3516 609E 681 46,7B 0.069 20.814 1,249 3516 503E 568 39.57 0.070 17.573 1,054 3515 403E 454 32.47 0.072 14,445 967 3516 309E 341 25.25 0.074 11.317 679 3516 253E 224 21.82 0.077 9.792 597 3515 209E 227 19.47 0.081 8.246 495 3516 109E 114 11.91 0.105 5.232 314 Electric Power Systems, Inc. Arctic Blvd Suite 201 ■ Anchorage, Alaska 99503 ■ Tel: (907) 522-1953 The last and third -to -last columns are calculated trivially from the other columns. Due to the limited access to performance data, these two performance data sets were mapped to all of the existing gensets as an approximation, even though each genset will have varying performance. This data will be used as described later in the analysis. The record data of power delivered to distribution is shown in excerpt below: #Of Tags Sample Rate = 00:15:00 Old Feeders New Feeders Y Y Y n n 01 m = = m ln- ln,i m 'i m ids x Fj v OI LL N 01 OZ [n �I 7/16/20 9:00 3,343.09 889.11 1,174.54 4,220.49 853.21 1,292.93 154.99 11,929.35 7/16/20 9:15 3,321.12 931.65 1,083.59 4,223.03 880.5 1,231.92 158.04 11,829.95 7/16/20 9:30 3,451.65 902.83 1,220.66 4,283.67 847.5 1,304.34 164.43 12,175.59 7/15/20 9:45 3,595.64 969.54 1,370.66 4,261.79 816.97 1,297.93 163.14 12,455.55 7/16/20 10:00 3,560.39 870.07 1,406.89 4,282.75 741.14 1,292.71 165.13 12,319.13 7/16/2010:15 3,485.52 873.33 1,424.87 4,206.66 760.8 1,325.23 164.72 12,241.13 7/16/2010:30 3,521.94 892.59 1,472.79 4,207.49 769.85 1,357.46 165.35 12,387.46 7/16/2010:45 3,571.55 972.94 1,430.85 4,228.32 814.18 1,324.33 168.04 12,510.71 7/16/20 11:00 3,630.18 1,014.48 1,393.25 4,278.33 828.23 1,296.01 167.88 12,598.36 7/16/20 11:15 3,613.05 1,012.71 1,429.34 4,248.01 830.2 1,317.33 173.45 12,629.60 7/16/20 11:30 3,684.50 1,040.09 1,482.32 4,269.07 844.42 1,346.93 170.21 12,837.54 7/16/2011:45 3,637.54 1,049.47 1,428.28 4,249.130 851.3 1,319.60 170.94 12,707.03 7/16/2012:00 3,695.17 1,030.91 1,485.89 4,277.513 834.71 1,341.72 172.77 12,838.76 7/16/2012:15 3,646.80 962.55 1,421.69 4,301.20 787.15 1,295.10 172.39 12,586.99 7/16/20 12:30 3,685.86 968.42 1,346.06 4,369.21. 780.05 1,220.39 172.52 12,543.01 7/16/2012:45 3,765.70 939.71 1,411.67 4,415.76 747.93 1,247.00 174.5 12,702.17 7/16/20 13:00 3,742.09 876.99 1,362.94 4,448.85 706.31 1,200.23 173.8 12,511.21 7/16/20 13:15 3,784.31 921.65 1,451.20 4,418.75 733.96 1,269.24 181.75 12,760.76 7/16/2013:30 3,692.93 973.67 1,362.70 4,356.47 781.71 1,230.44 183.63 12,581.55 7/16/2013:45 3,644.51 926.76 1,301.45 4,363.61 748.34 1,197.29 197.22 12,359.19 7/16/2014:00 3,592.36 951.4 1,247.78 4,334.29 772.67 1,163.42 184.81 12,246.72 7/16/20 14:15 3,587.55 925.29 1,225.33 4,352.06 750.51 1,140.43 186.4 12,167.57 7/15/2014:30 3,567.34 875.5 1,248.77 4,355.47 721.95 1,153.77 182.66 12,105.37 7/16/2014:45 3,619.12 878.83 1,243.75 4,390.52 711.88 1,143.09 185.43 12,172.62 7/16/20 15:00 3,597.71 877.89 1,248.08 4,370.50 713.83 1,147.78 187.04 12,142.93 7/16/2015:15 3,602.97 872.99 1,281.42 4,360.30 711.29 1,194.60 195.23 12,208.90 7/16/20 15:30 3,745.68 933.56 1,353.90 4,421.95 742.19 1,209.58 200.31 12,607.17 7/16/20 15:45 3,641.83 906.11 1,320.43 4,357.19 734.21 1,210.02 204.85 12,374.54 7/16/2016:00 3,689.84 925.76 1,296.03 4,402.99 739.6 1,177.25 200.04 12,431.40 7/16/20 16:15 3,687.68 894.89 1,237.37 4,443.75 706.69 1,129.06 205.83 12,304.26 7/16/2016:30 3,740.62 916.12 1,204.89 4,496.39 715.01 1,097.70 198.11 12,358.94 7/16/2016:45 3,594.46 883.34 1,132.20 4,418.61 707.94 1,069.41 202.47 12,007.43 7/16/2017:00 3,589.38 874.1 1,149.01 4,412.69 708.54 1,079.15 196.76 12,009.73 7/16/20 17:15 3,583.78 869.63 1,183.22 4,393.34 704.75 1,106.58 202.38 12,048.69 7/16/2017:30 3,689.99 926.4 1,269.51 4,416.61 733.13 1,157.51 196.41 12,389.56 7/16/20 17:45 3,742.55 937.23 1,346.88 4,415.39 738.94 1,203.52 202.35 12,586.86 There are approximately 70,000 records, or 729 days of logged data. After filtering known bad data, approximately 53,750 records, or 560 days, remain. After this, the data is re -averaged from 15-minute windows to 6-hour windows. Due to the relatively consistent loading, this has minimal impact to the analysis results. Electric Power Systems, Inc. 3305 Arctic Blvd Suite 201 ■ Anchorage, Alaska 99503 ■ Tel: (907) 522-1953 ANALYSIS PROCEDURE For each genset, the prime kW nameplate capacity is procured: UnI.ID Si- -iIa_eAs Prime k'h 9 1 2 3 4 10 5 6 7 11 12A 12B 13 14 35_6 3512B 35_2B 35_2B 35_2B 3516 3512E 3512E 3512E 3512E 3512E 3512E 3512E 3512E 1.135 355 865 865 1,322 1,135 1,050 1,050 1,050 1,360 S00 900 3,300 3,300 The nameplate capacity is then modified by a preferred capacity %, which is the % load that the operators prefer not to exceed for each given genset. This has minimal impact to the analysis results, but helps the data better match the real -world conditions. Uni-ID 9 1 2 3 4 16 5 6 7 11 12A 12B 13 14 S'-.Ala_e As 3516 3512B 3512E 3512E 3512E 3516 3512E 3512E 3512E 3512B 3512B 3512E 3512B 3512B Prime VA' 1,135 865 865 865 1,322 1,135 1,050 1,050 1,050 1,360 500 900 3,300 3,3oo Preferred 76% 75% 75% 75% 7M* 76h 72% 72% 7235 100% 100% 100% 100% 100% Pref. kw 863 649 649 649 925 863 756 756 756 1,360 500 900 3,300 3,3oo The gensets are then ordered by their stage order. This is the theoretical order that gensets are brought online as the load increases. The order is approximate, as it can be varied by the operators for a variety of reasons. The exact order will have minimal impact to the analysis results, but the staging order used was created based on our best understanding of the operator's preferrences, and is held constant across all records and scenarios to simplify the analysis. With the stage order developed, a capacity for each stage is developed. This is the sum of preferred kW for all gensets operating in that staging profile: Unit ID 9 1 2 3 4 16 5 6 7 11 12A 12B 13 14 SirnuIate As 3516 3512B 3512E 3512E 3512E 3516 3512E 3512E 3512E 3512E 3512E 3512E 3512E 3512E Prime h%1 1,135 865 865 865 1,322 1,135 1,050 1,050 1,050 1,360 900 900 3,300 3,300 Preferred 76% 75% 75�i 75�i 70�6 76h 72?6 72?6 72?6 100% 100% 100% 100% 100% Pref. kW 863 649 649 649 925 863 756 756 756 1,360 900 900 3,300 3,300 Staging Order 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Stage M 863 1.511 2,150 2,809 3,734 4,597 5,353 6,1C9 6,865 8,225 9.125 10.025 13,325 16,625 This setup so far is identical for both the existing and future scenarios, but this next step is what separates the existing and future scenarios. The next step is to modify the stage capacity based on the scenario requirements to represent the capacity available to handle the distribution load. Where reserve spin is required, the stage kW previously calculated is modified by subtracting the largest single genset from the stage MW. In simple terms, the stage and scenario capacities are as follows: S stage kW, = Z genset pref kWi i=1 scenario kW = stage kW - max(genset kW[1,...S]) Where s is the stage number, and subscript [1,... s] represents an array of gensets applicable to that stage. per' Electric Power Systems, Inc. Arctic Blvd Suite 201 ■ Anchorage, Alaska 99503 ■ Tel: (907) 522-1953 Unit ID 9 1 2 3 4 10 5 6 7 11 12A 12B 13 14 Simulate As 3515 3512E 35128 35128 3512B 3516 3512E 3512B 3512B 3512B 3512E 3512E 3512E 35120 Prime kW 1,135 865 865 865 1,322 1,135 1,050 1,050 1,050 1,360 900 900 3,300 3,300 Preferred 76% 75% 75% 75% 70% 76% 72% 72% 72% 100% 100% 100% 100% 10096 Pref. kW 863 649 649 649 925 863 756 756 756 1,360 900 900 3,300 3,300 Staging Order 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Stage kW 863 1,511 2,160 2,S09 3,734 4,597 5,353 6,109 6,855 8,225 9,125 10,025 13,325 16,625 Scenario kW 0 649 1,298 1,946 2,809 3,671 4,427 5,183 5,939 6,865 7,765 9,665 10,025 13,325 For the future scenario, where no spin is required, the only change required is with the scenario kW. From before, the stage kW is calculated as: s stage kW = E genset pref kW. S i=1 While the scenario kW is calculated by removed the largest genset to account for spin: scenario kW = stage kW - max(genset kW[1.... S]) With the future scenario, the scenario kW does not have to be derated by the spin, and thus the full genset capacity is available, and thus the scenario kW is simply the stage kW: scenario kW = stage kW Unit ID 9 1 2 3 4 10 5 5 7 11 12A 12B 13 14 Simulate As 3516 3512E 3512E 3512E 3512E 3516 3512E 3512E 3512E 3512E 3512E 3512E 3512E 3512E Prime kW 1,135 865 865 865 1,322 1,135 1,050 1,050 1,050 1,360 900 900 3,300 3,300 Preferred 76% 75% 75% 75% 70% 76% 72% 7296 72% 100% 10096 100% 100% 100% Pref. kw 863 649 649 649 925 863 756 756 756 1,360 900 900 3,300 3,300 Staging Order 1 2 3 4 5 6 7 S 9 10 11 12 13 14 Stage kW 863 1,511 2,160 2,809 3,734 4,597 5,353 6,109 6,865 8,225 9,125 10,025 13,325 16,625 Scenario kW 863 1,511 2,160 2,809 3,734 4,597 5,353 6,109 6,865 8,225 9,125 10,025 13,325 16,625 At this point, we have set up our genset and staging information developed, and now we can turn our attention to the record data. First, we calculate the number of generators needed to satisfy the load for each record. This is performed by taking the record load and "climbing" up the stage order to find a scenario kW capacity that will satisfy the record load. Next, the load % is determined by taking the record load and dividing it by the stage kW. Note that by determining the number of generators by the scenario kW, but determining the load by the stage kW, we are accounting for the lower generator loading due to the spin requirements. I Record: 11/15/1911 11/15/19 17 Rec kW 971.66 1603.49 Unit ID Simulate As Prime kW Preferred Pref. kW Stating Order Stage kW Scenario kW Hours # Gens Load 6.0 3 45% 6.0 4 57% 1 2 3 4 5 6 7 . 3 13 14 = G H I J I K I L I M H 0 P R S 9 1 2 3 4 10 5 6 7 11 12A 12B 13 14 3516 3512B 3512B 3512B 3512B 3516 3512B 3512B 3512B 3512B 3512E 3512E 3512B 3512B 1,135 865 865 865 1,322 1,135 1,050 1,050 1,050 1,360 900 900 3,300 3,300 76% 75% 75% 75% 70% 76% 72% 72% 72% 100% 100% 10D% 100% 100% 863 649 649 649 925 863 756 756 756 1,360 900 900 3,300 3,300 1 2 3 4 5 6 7 8 9 10 11 12 13 14 863 1,511 2,160 2,809 3,734 4,597 5,353 6,109 6,865 8,225 9,125 10,025 13,325 15,625 0 649 1,298 1,946 2,809 3,671 4,427 5,183 5,939 6,865 7,765 8,665 10,025 13,325 GAL GAL GAL GAL GAL GAL GAL GAL GAL GAL GAL GAL GAL GAL 169 142 142 0 0 0 0 0 0 0 0 0 0 0 210 169 169 169 0 0 0 0 0 0 0 0 0 0 (spreadsheet excerpt showing the existing scenario and the first two records) per' Electric Power Systems, Inc. 3305 Arctic Blvd Suite 201 ■ Anchorage, Alaska 99503 ■ Tel: (907) 522-1953 For each staged generator (i) and each record (k), the fuel used is calculated by the following: genset GALik = GensetlnterpolateGPHperkW,(load%k * preferred%d * load% * preferred kW, * hours Where Gensetlnterpolate GPHperkWI. is a custom function that interpolates the genset performance data based on the prime loading (load%k * preferred%i) and provides the fuel performance in units of GPH of fuel per kW. This is then multiplied by the prime load (load% * preferred kW,L ) to get GPH consumption of the genset at that record, and then multiplied by the record hours (hours k) to get the total gallons of fuel consumed during that record period. Between the existing and future scenarios, the calculations are the same, but the results change due to the difference in scenario kW between the two scenarios. See the following calculation excerpt for reference (records start on row 13; existing scenario are in columns E-J, and the future scenario are in columns W through AB): 1 Unit ID 9 1 2 3 4 Unit ID 9 1 2 3 4 2 Simulate As 3516 3512B 3512E 3512E 3512E Simulate As 3516 3512B 3512B 3512B 3512B 3 Prime kW 1,135 865 865 865 1,322 Prime kW 1,135 865 865 865 1,322 4 Preferred 76% 75% 75'h 75)� 76'h Preferred 76% 75% 75% 75% 70% 5 Pref. kW 863 649 649 649 925 Pref. kW 863 649 649 649 925 6 Staging Order 1 2 3 4 5 Staging Order 1 2 3 4 5 7 Stage M 863 1,511 2,160 2,809 3,734 Stage M 863 1,511 2,160 2,309 3,734 a Scenario kW 0 649 1,298 1,946 2,809 Scenario M 863 1,511 2,160 2,809 3,794 ' 12 Record: Rec kW Hours »Gens Load GAL GAL GAL GAL GAL » Gens Load GAL GAL GAL GAL GAL 1E 11/15/19 11 971.66 6.0 3 45% 169 142 142 ., 0 2 64% 233 184 0 0 0 14 11/15/19 17 1603.49 6.0 4 57% 210 169 169 169 0 3 74% 255 206 206 0 0 (spreadsheet excerpt hiding all but the first 5 gensets and the first two records) Note how for the same record, the existing scenario has more operating gensets at a lower, less efficient, loading, whereas the future scenario has fewer gensets more efficiently loaded, due to the removal of spin requirements allowed by the BESS. The remaining calculations for run hours or heat rejection simply require replacing the genset GAL i,k calculation with the alternate calculations for run hours and heat rejection To develop per -month totals, the fuel consumption can be summed across the gensets by record, and then this subtotal can be summed across all records filtered by month. Due to the records representing more than one year, the resulting total represents more than one month of data. Thus the total is made uniform by multiplying by the ratio of the number of annual hours in the subject month to the sum of the record hours in the subject month. Eg, if the total gallons of fuel for all records in January was calculated as 51,858 gal, and the record data represented 1,488 hours of data for January, the 51,858 gal would be multiplied by the ratio of the number of annual hours in January (31 days * 24 hours = 744 hours) to the records hours: Jan fuel consumption = calculated record gallons * annual Jan hours / recorded Jan hours Jan fuel consumption = 51, 858 gal * 744 hours/1, 488 hours = 26, 793 gal The remaining calculations simply require replacing the genset GAL i k calculation with the alternate calculations for run hours and heat rejection. Electric Power Systems, Inc. Arctic Blvd Suite 201 ■ Anchorage, Alaska 99503 ■ Tel: (907) 522-1953 The tab "Data Summary" shows the summary of the longhand analysis noted above. Specifically, it extracts out the per -month results from the above, longhand calculation procedure. Additional calculations are there derived, including an approximate O&M cost savings estimate. ANALYSIS SUMMARY The following results are shown on the "Data Summary" tab. Fuel usage, runtime, JW heat rejection, and electrical production: FUELUSAGE I F- RUNTIME 1W MMBH REJECTION ELECTRICAL PRODUCTION EXISTING FUTURE SAVINGS SAVINGS EXISTING FUTURE SAVINGS SAVINGS EXISTING FUTURE REDUCTION REDUCTION (NOCHANGE) Month GAL GAL GAL % EXIST. HOURS HOURS HOURS % EXIST. MMRTH MM6TU MMBTU % EXIST. Peak kW Low kW kWh January 100,192 93,316 6,876 6.9% 3,201 2,241 960 30.0% 2,793 2,452 301 10.8% 2,243 1,404 1,350,262 February 96,022 91,099 4,924 5.7% 2,735 1,995 740 27.0% 2,384 2,170 214 9.0% 2,103 1,458 1,169,917 March 95,915 91,486 5,429 5.6% 3,036 2,225 811 26.7% 2,681 2,444 236 8.8% 2,198 1,391 1,322,708 April 102,056 95,135 6,921 6.9% 3,180 2,253 927 29.2% 2, 840 2,535 305 10.7% 2,981 1,650 1,380,309 May 170,379 153,057 7,312 4.3% 4,464 3,542 822 18.4% 4,655 4,327 329 7.1% 7,404 685 2,359,410 June 176,369 170,502 5,867 3.3% 4,510 3,773 738 16.4% 4,795 4,531 264 5.5% 3,397 976 2,473,725 July 459,582 450,025 9,557 2.1% 9,886 8,059 828 9.3% 12,291 11,740 551 4.5% 12,394 3,594 6,559,673 August 102,627 95,597 7,029 6.8% 3,246 2,244 1,002 30.9% 2,857 2,550 307 10.8% 4,019 1,321 1,386,500 September 90,563 73,722 6,840 8.5% 2,862 1,739 1,123 39.2% 2,268 1,976 291 12.9% 1,647 943 1,065,685 October 83,451 76,270 7,181 8.6% 2,964 1,784 1,180 39.8% 2,349 2,043 306 13.0% 1,746 301 1,103,959 November 83,551 77,505 6,045 7.2% 2,857 1,995 971 34.0% 2,238 2,078 259 11.1% 1,827 579 1,117,207 December 92,140 85,968 6,172 6.7% 3,036 2,088 948 31.2% 2,559 2,301 267 10.4% 2,180 1,348 1,240,841 Year: 1,533,846 1,553,6133 80,154 4.9% 44,977 33,929 11,048 24.6% 44,819 41,188 3,631 8.1% 49,130 15,640 22,540,197 O&M cost savings estimate (using the runtime hours savings): GENSET O&M SAVINGS 09LM Record Costs: 2020 $422,215 2021 $641,203 2022 $573,063 Ave O&M/year: $545,494 Runtime Savings: 24.696 O&M Savings: $133,992 Attachments: NEA BESS Scenario Analysis