Puget Sund Cmpany Overview Puget Sund Energy is Washingtn State s largest and ldest energy utility, serving nearly 1 millin electric custmers and mre than 650,000 natural gas custmers, primarily within the Puget Sund regin. Puget Sund Energy became a cmbined energy cmpany in 1977 with the merger f Puget Sund Pwer & Light C. and Washingtn Energy Cmpany (parent f Washingtn Natural Gas). We currently serve gas and/r electric t custmers in 11 cunties in Washingtn cvering almst 7,000 square miles f service territry. Purpse f the Prject This prject was undertaken in supprt f a Cst f Service (COS) review t determine if rate adjustments were warranted. It was crucial t have a fair way t allcate this cst fr specific custmers when any particular pipe serves many. Taking advantage f ur system mdel we cntracted with Advantica t create a prcess that wuld determine the percent utilizatin f each facility that was used t serve a custmer. Each segment cst culd then be brken dwn and allcated apprpriately. Slutin Overview In reviewing the prject requirements, there was n single applicatin that culd meet the required scpe. The end slutin had t prvide slid hydraulic results accmpanied by a flexible graphic representatin f thse results. Advantica s netwrk analysis package, SynerGEE Gas, culd prvide the hydraulic results, but was limited in its ability t prvide the results thematically. As a result, Advantica designed a slutin that integrated SynerGEE with ArcGIS. A general verview f the slutin is prvided belw. Beginning with a balanced hydraulic mdel frm SynerGEE, the exprted mdel and a new pipe cntributin reprt are imprted int ArcView via a custm applicatin built by Advantica. This cmbinatin cupled with further data gathering n pipe segments and custmers create an envirnment t prduce accurate COS calculatins. - 1 -
The remainder f this paper will prvide mre details n key parts f the slutin. Netwrk Analysis Netwrk analysis r cmputer based mdeling is a cre technlgy that has been in use by natural gas utilities fr mre than 40 years. A hydraulic mdel prvides a cmprehensive lk at a system s pressures, flws, gas prperties, and custmer prtfli. The mdel prvides an engineer with insights int the netwrk s deficiencies and capabilities. Histrically, gas utility cmpanies use the netwrk analysis technlgy daily in planning grups t: Design and determine the need fr capacity based capital imprvements Supprt field peratins planning (i.e. cnsequences f perating a valve, when t take a main ut f service, bypass requirements) Apprve prpsed lads n the system Supprt gas supply thrugh line pack calculatins and in decisins t interrupt custmers In mre recent years, netwrk analysis s rle in the gas utility has expanded t incrprate tasks that are fcused n the cmpany s financial planning. Utilities are relying n netwrk mdels t determine the rate f return fr a particular asset, the cst t service a new custmer, the csts r benefits frm purchasing gas frm varius supplies, including LNG. In tday s wrld f increasing whlesale prices fr natural gas and the added pressure t increase returns, netwrk analysis has prven t be a very valuable resurce. Pipe Cntributin One f the key design aspects f ur slutin fr calculating the cst f service was the determinatin f the pipes cntributing t the service f a custmer. In ther wrds, which pipes cntribute t the flw f natural gas frm the gate statin t an individual custmer s service line? In rder t determine the pipe flw path, we turned t netwrk analysis fr the answer. SynerGEE Gas, Advantica s netwrk analysis sftware, prvides PSE with flw and pressure calculatins fr their 120,000 nde mdel. The prgram als prvides flw directin fr each pipe in the mdel. The limitatin, hwever, invlved the ability t single ut an individual custmer, and t visualize that custmer s flw path alng with the percent cntributin f each pipe alng the path. The percent cntributin was vital t the slutin since pipes are used t serve mre than ne custmer within the system. In rder t determine the cst f service fr a particular custmer, that custmer s prtin f the pipe s flw must be islated. When it was first decided t investigate the capabilities f using SynerGEE, it was nticed that the ability t reprt n the pipe cntributin fr each custmer r nde in the hydraulic mdel was nt available. At that pint, PSE cntacted Advantica t investigate the pssibilities f enhancing the sftware t include the pipe cntributin infrmatin. Advantica was receptive t the idea and added tw new features t the prgram. The first feature that was added was a backwards trace f the pipe netwrk frm custmer t surce. This capability wuld enable PSE t select any nde in the mdel - 2 -
and have SynerGEE trace the pipe netwrk frm the nde t the supply f gas. As SynerGEE traced back thrugh the netwrk it wuld determine hw much f the gas flwing thrugh each pipe alng the flw path was cntributing t the demand f the custmer selected in the mdel. By determining the percent f gas ging t the custmer, SynerGEE culd calculate the percent cntributin f that pipe by dividing the prtin f the custmer gas in that pipe by the ttal flw thrugh the pipe. The secnd feature that was added was a Pipe Cntributin Reprt. This feature required that results frm the backwards trace be summarized in a frmat that was easy t read and easy t integrate with ther surces f system data. Functinality was added t review the reprt directly in SynerGEE as well as t exprt the data int a frmat readily accessible by the Cst f Service applicatin in ArcView. The required steps in SynerGEE are: Select the desired ndes fr prcessing (the initial prject nly evaluated Nninterruptible gas custmers, abut 800 in the ttal mdel). The subset is easily stred and selected via a SynerGEE Partial Chapter. Generate the Pipe Cntributin Reprt (shwn belw). This must be dne n a balanced mdel, making sure t select the reprting range f Selected Ndes nly. - 3 -
The reprt frmat is designed t shw the results fr each individual COS nde. In the reprt abve, the first nde selected is ID7613. This nde has a lad f 171 SCFH. Fllwing the brief nde descriptin, a tabular reprt f the pipe cntributin results is displayed. Each pipe that serves the nde is listed in the left hand clumn (FID). The pipe cntributin results are displayed in clumns fur and five. Percentage f Pipe Flwing Cntributing t the Lad This is the percentage f the ttal pipe flw cntributing t the nde s lad. Fr FID EQ125109 this is 100 %. Reviewing the mdel will shw that this nde nly has ne pipe delivering gas t nde ID7613 and that pipe is EQ125109. N ther custmers are lcated alng this pipe. Percentage f Lad Flwing in Pipe This value is based n the ttal nde lad rather than the ttal pipe flw. This value will prvide the percentage f the nde s ttal flw that the pipe cntributes. S rather than divide by the ttal pipe flw, this calculatin uses the ttal nde lad. Flw Flw ging thrugh the pipe Length, Diameter, and Rughness Pipe attributes The reprt and mdel must be exprted frm SynerGEE t the COS applicatin in ArcView. The reprt is saved as a text file while the mdel is saved as a database file. Cst f Service Applicatin One f the gals fr this prject was t create a prcess that enabled the user t visually see the gas flw path frm custmer t surce and easily integrate thse results with ther data surces. The chsen platfrm fr this data display and integratin was ESRI s ArcView applicatin. ArcView s pwerful mapping engine and pen envirnment enables any user t imprt and exprt data easily and efficiently. In rder t integrate the SynerGEE pipe and regulatr data alng with the Pipe Cntributin Reprt, Advantica created a custm applicatin within the ArcView envirnment. This applicatin pulls all this data tgether and creates a tl that enables the user t create plts f the gas flw path fr each custmer, thematically map cst f service data, and exprt shape files r tables f infrmatin fr each custmer. The COS applicatin tlbar cntains fur buttns, a brief descriptin f each is prvided belw. - COS Nde Selectin enables the user t select a COS Nde and view the gas flw pathway frm the surce t the COS Nde. - Build Prject enables the user t cnvert the SynerGEE dataset t a frmat cmpatible with ArcView. Als establishes initial ArcView prject file. - 4 -
- Shape File Cnverter enables the user t cnvert any SynerGEE mdel t a shape file. The shape file can then be pened in ArcView. - Cnvert Cntributin Reprt enables the user t cnvert any Pipe Cntributin reprt frm SynerGEE t a table in ArcView. The rder f events that must ccur t visualize the results in ArcView is first the Prject must be Built this peratin cmbines the mdel graphics (mdb exprt) and the pipe cntributin reprt (text file save) int a persnal gedatabase. This Build activates the COS nde selectin ptin allwing analyzing f a single custmer t its surce supply. In the picture abve the symblgy is as fllws: - Surce ndes in the mdel. All COS results are calculated frm the COS nde t a surce nde. - COS nde as specified in SynerGEE. These are the ndes that PSE has specified t determine the cst f service. The multiclred pipes represent the COS pipes. This a ttal visual representatin f all the pipes that service at least ne f the COS ndes. Fr this data set, the mdel cntained 129,374 ttal pipes. Of the 129,374 pipes, 13,966 are COS pipes that service at least ne nde. - 5 -
- Represents regulatrs in the system (pipe with n length, diameter, rughness) - The gray pipe represents the all the SynerGEE pipes T trace a specific custmer, click n the Select COS Nde tlbar buttn. Using yur muse, select ne f the range COS ndes. When a nde has been selected, ArcView will highlight the pipes that the gas travels thrugh frm the surce nde t the COS nde. Using standard ArcView functins ndes can be labeled, maps can be created, individual runs can be exprted, and attribute data can be extracted fr use in ther applicatins. Cst f Service Calculatins With the pipe cntributins nw calculated, additinal data was added fr each segment and each custmer. Using the visual created frm ArcView it was pssible t supplement and cnfirm the infrmatin riginally cntained within the SynerGEE mdel. Attributes added t the pipe cntributin table included installatin date and pipe material. The prcess als validated segment length and diameter. T get a cmplete COS, the service cnnectin fr each custmer was researched and infrmatin n pipe length, diameter, material, and year installed were all gathered. Since the gas recrds span mre then 100 years there was n ne system that cntained all the pertinent infrmatin fr calculating a COS. Thus prtins f this prcess were rather manpwer intensive. After everything was in place, the COS team applied cst t each segment and service cnnectin depending n all f the available variables. The service cst was applied at - 6 -
100% while each f the segment s percent utilizatin was multiplied by the ttal cst t btain the incremental cst fr that custmer. In Cnclusin This prject hinged n the ability t accurately determine utilizatin f pipe. The integratin f SynerGEE and ArcView made an extremely difficult prject manageable. The ability f tls t supprt planning, peratins, and financial prcesses is indicative f hw slutins can and need t serve the enterprise. - 7 -