Reliability Centered Asset Management (RCAM)

Transcription

1 Reliability Centered Asset Management () Aiming at Energy Efficient Transmission & Distribution System IRFAN AHMAD (FIEEEP).

2 Energy Management & Energy Audit Electrical Utilities Energy Management: Optimization of energy systems and procedures to increase energy efficiency and reliability. Energy Audit: A systematic approach in the area of Energy Management to verify, monitor and analyze the energy streams in a Utility. This includes recommendations to improve energy efficiency and action plan to reduce energy losses. (Source: Bureau of Energy Efficiency, India) Page 1 Irfan Ahmad

3 Energy Audit The main aim is to improve energy efficiency Energy audit involves the following 3 elements of a T&D System: 1) Processes: GoP is looking at the bigger picture; Deregulate, Privatize Dawn ) Manpower: Fire before hire is the new guideline. Take care of pounds, the pennies will.. 3) T&D System: (Paradigm shift required) Outdated, weak and un-reliable An important 4 th element outside the T&D System, whose participation is necessary in improving energy efficiency, is the Consumer. A Consumer in Pakistan requires urgent awareness about his role. Page 2 Irfan Ahmad

4 Resolving the energy crisis 1) Energy Conservation Hybridisation Smart grids 2) Energy Efficiency Loss reduction Asset Management (We need to know where we stand) 3) Energy Generation Renewables Alternative Conversion Page 3 Irfan Ahmad

5 Netherlands USA South Africa France UK Kenya Brazil Ghana India Tanzania Pakistan Nigeria Uganda % Losses Total Electrical Losses of some typical countries Dawn The main issue with our utilities are the energy losses on constant increase. Losses vary from DISCO to DISCO. On the average the total losses are around 30% Example: KESC: Total Average Energy Losses > 40% - (as declared by KESC) FESCO: Total Average Energy Losses = 14% - (as declared by FESCO) Page 4 Irfan Ahmad

6 How big are the utility losses in Pakistan Total units sold in 2012 * = 79 x 10 9 Units Average tariff = Rs. 15 per Unit Total revenue / year = Rs. 15 x 85 x 10 9 = Rs Billion Total loss (>30%) / year = Rs. 360 Billion Technical losses / year = Rs. 100 Billion Possible recovery of revenue loss (over 3 years) by simple methods of loss reduction is > 15% which is equivalent to Rs. 180 Billion / year. * Key World Energy Statistics 2012, IEA Page 5 Irfan Ahmad

7 Various Types of Losses Only approximate total losses for Pakistani utilities are known None of the utilities know the exact amount of technical & non-technical losses Two different type of losses: - Technical Losses such as I 2 R Losses - All other losses are Non-Technical Losses where Illegal connections (theft) constitute a major portion KESC: Total Losses 40% Technical Losses 20% Non-Technical 20% FESCO: Total Losses 14% Technical Losses 7% Non-Technical 7% Page 6 Irfan Ahmad

8 Case 1: Load Flow Study of HV System Determining Technical Power Losses using Simulation Software Legend: 66kV 132kV Pvt grid Page 7 Irfan Ahmad

9 Determination of Losses by Load Flow Studies Power (kw) Losses are determined and converted into Energy (kwh) Losses by using following formula: Power Losses x (0.5 to 0.7) = Energy Losses Factor for Pakistani Utilities Eg. KESC=0.68 Major advantage Both technical & non-technical losses can be determined. Page 8 Irfan Ahmad

10 Case 2: Load Flow Study of MV Feeders of a Utility Result Summary: Technical Losses at MV Level Feeder Name No. of Consumer Tech. Losses Non- Tech. Losses Loss peryear PKR Investm. for Tech. loss reductn by 2% in PKR Revenue Saving PKR Return/ Investm. Ratio Investm. non Tech. loss reduction by 20% in PKR Revenue Saving PKR Return/ Investm. Ratio % 37% 51 M 15.0 M 3 M M 30 M % 51% 71 M 13 M 3 M M 28 M % 39% 50 M 20 M 2 M M 26 M % 30% 41 M 14 M 3 M M 27 M 0.44 Page 9 Irfan Ahmad

11 Probabilistic reliability analysis Overview Schematic sequence of probabilistic reliability analysis Past system performance Observable Supply reliability indices Failure models Component reliability data Assessment / Prognosis Reliability Calculation Observable Comparison Future system performance Page 10

12 Asset Management - Basic characteristics Share of the outage performance with possible relation to external influence in electrical power supply networks Example: Share of outage events per outage occasion in MV (nominal voltage above 1 kv up to 36 kv, ) 3,4% 2,6% 5,9% 8,4% 1,3% 2,4% 6,9% 5,2% 3,6% 35,7% No identifiable occasion Thunderstorm Storm Moisture Other atmospheric influences Animals and birds Trees Excavations Other third-party influences Failures in other networks Other 24,7% Source: VDN-Störungsstatistik Page 11 Irfan Ahmad

13 Asset Management Basic characteristics Share of the outage performance with possible relation to external influence on individual components in electrical power supply networks Example: Share of outage events per outage occasion in MV (nominal voltage above 1 kv up to 36 kv, ) 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Overhead line Cable Transformer Stations and switchgear Other Failures of other networks Other Third-party influences Excavations Trees Animals and birds Other atmosph. influences Moisture Storm Thunderstorm No identifiable occasion Source: VDN-Störungsstatistik Page 12 Irfan Ahmad

14 Reliability Centered Asset Management () Key Challenge: Balance Cost Efficiency & System Efficiency Reliability Centered Asset Management Reliability of network components Analysis / Prognosis Cost calculation Operational expenses Reliability calculation Supply reliability Synthesis Optimized Asset Management Strategies Page 13

15 Reliability Centered Asset Management - Overview Objective Securing Cost Efficiency, reliability and power quality in electrical power supply networks (System Efficiency) Method Analysis of current asset management methods Description of the current situation Identification of cost-saving capabilities Systematic analysis of the network Prioritization of network components Synthesis of optimized asset management strategies Analysis of effects of cost-saving measures Assessment of different asset management strategies Result Determination of optimized asset management strategies Page 14 Irfan Ahmad

16 Example Component Condition Assessment Scheme for component condition assessment Importance Attribute Quality Weight Description Detail Description Value factor 0-50 % 0 Age (related to std. service life) Serviceability Spare parts availability Availability of skilled staff Cost level % % % 21 > 100 % 30 Fair 3 Poor 5 Fair 3 Poor 5 Low 0 Normal 1 High 3 Very High Importance Attribute Quality Weight Description Detail Description Value factor Indoor/Outdoor Indoor 0 Outdoor 5 Low 0 Ambient Cond Environmental Normal 1 10 stresses High 3 Very High % 0 Peak Loading % 3 (related to th. capacity) % > 95 % 15 Operational experience Good 3 Fair Poor 15 Condition assessment (( Details: See details Next Slide )) 20 Page 15 Irfan Ahmad

17 Example Component Condition Assessment Scheme for assessment of physical condition Importance Attribute Quality Weight Description Component classdetail Description Value factor Poles Fair 3 Poor 7 Overhead lines Cross arms Fair 3 20 Poor 7 Conductor Fair 3 Poor 7 Leakages Fair 2 Poor 4 Corrosion Fair 2 Poor 4 Condition assessment Oil desiccant Fair 2 Poor 4 20 Painting Fair 2 Transformers Poor 4 Bushings Fair 2 Poor 4 Tap changer Fair 2 Poor 4 Good 0 Oil condition Normal 2 2 Poor 5 Good 0 Cooling system Normal 2 2 Poor 5 Importance Attribute Quality Weight Description Component classdetail Description Value factor Cable termination Good 3 Fair 6 Poor Cables Good 3 Leakages Fair 6 Poor 10 Good 0 Serving test Normal 2 2 Poor 5 Leakages Fair 2 Poor 4 Corrosion Fair 2 Poor 4 Condition assessment Connections Fair 2 Poor 4 20 Switchgears Painting Fair 2 Poor 4 Secondary Equipment Fair 2 Poor 4 Enclosure / Building Fair 2 Poor 4 Good 0 Sealing / Pressure Normal 2 (GIS only) Poor 5 2 Good 0 Partial Discharge Normal 2 2 Poor 5 Page 16 Irfan Ahmad

18 Example Component Importance Assessment Scheme for component importance assessment Importance Attribute Weight factor Quality Identifier Description Description Value EENS Share of system EENS 50 Individual results 0-50 < 50 0 CustNo No. of customers disconnected on failure 25 CustCrit Criticality of customers 15 AssetCrit Criticality of component > Rural 0 Residential 3 Large Industrial 7 Commercial 11 City Center 15 Low 0 Normal 10 High 14 Very High 20 Page 17 Irfan Ahmad

19 Condition Prioritization of network components 1,0 0,9 0,8 0,7 0,6 0,5 0,4 0,3 Switchgear Transformers Cables Overhead Lines 0,2 0,1 0,0 0,0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1,0 Importance Page 18 Irfan Ahmad

20 Condition Condition Condition Condition Condition Optimized asset management strategies 1,0 1,0 0,9 0,9 0,8 CB-D 1,0 0,9 0,8 TR-D 0,7 0,8 0,6 0,5 0,7 0,4 0,6 0,2 0,1 0,5 1,0 0,4 0,9 0,8 0,3 0,7 CB-A CB-B CB-C Switchgear 0,3 0,0 0,0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1,0 CA-C Importance 0,7 0,6 TR-A 0,5 TR-B TR-C 0,4 Transformers 0,3 0,2 0,1 0,0 0,0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1,0 1,0 0,9 0,8 0,7 OL-C Importance Switchgear Transformers Cables Overhead Lines 0,6 0,2 0,5 0,4 0,1 0,3 CA-A CA-B Cables 0,6 0,5 0,4 0,3 OL-A OL-B Overhead Lines 0,2 0,0 0,1 0,0 0,1 0,2 0,3 0,4 0,5 0,0 0,6 0,7 0,8 0,9 1,0 0,0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1,0 0,0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1,0 Importance Importance 0,1 0,0 Importance 0,2 Page 19 Irfan Ahmad

21 Condition Optimized asset management strategies 1,0 0,9 CB-D Risk = Occurrence probability x effect 0,8 0,7 0,6 CB-A CB-B CB-C Condition Importance 0,5 Cost reduction 0,4 0,3 Switchgear Curves of constant risk 0,2 0,1 0,0 0,0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1,0 Importance Reliability reduction Page 20 Irfan Ahmad

22 Condition Case 3: Prioritization of Components Expediting Transformers Service to increase Reliability 1,0 0,9 0,8 0,7 0,6 CB-D CB-A CB-B CB-C Importance Criteria In-laws in the vicinity Risk of Law and Order Situation 0,5 0,4 0,3 0,2 0,1 0,0 0,0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1,0 Importance Condition Criteria Missing Protection Elements History of Stresses Oil Leakages Visual Appearance Condition of Transformer Oil Test Data Availability Page 21 Irfan Ahmad

23 Cost models Asset Management Strategies Definition of preventive maintenance tasks Definition of service life Influence on cost types Investment costs / net present value Costs for preventive maintenance Fault clearing costs Repair costs Interruption costs Cost models Simple models for approx. relevant effects Based on expected values of e.g. investment Page 22 Irfan Ahmad

24 Supply Unavailability in min/a Costs related to base scenario Case 4: Results of parameter studies Maintenance Costs of an HV Substation Supply unavailability Costs % % 400% 1 Kein Ersatz % 300% 2 (Teilw.) keine IH % % 150% 0 Basis % 50% 3 (Teilw.) red. IH % Supply unavailability Net pres. value Operating expenses 0 Base 1 No replacement 2 (Partly) No maint. 3 (Partly) reduced maint. Page 23 Irfan Ahmad

25 Conclusion Optimal Balance b/w Cost and System Efficiency Page 24 Irfan Ahmad

26 Thank you for your attention! Page 25 Irfan Ahmad