5/17/2000Summer Preparedness 20001

5/17/2000Summer Preparedness SRP SUMMER PREPAREDNESS 2000 Presented to the Arizona Corporation Commission May 17, 2000

5/17/2000Summer Preparedness Dave Areghini Associate General Manager, Power, Construction and Engineering Services

5/17/2000Summer Preparedness AGENDA b Summary of Year 2000 Projected Conditions and SRP Generating Plant Readiness b Resources and Reserves b SRP Transmission and Distribution System Readiness b Emergency Operations and Load Shedding

5/17/2000Summer Preparedness SUMMARY OF YEAR 2000 PROJECTED CONDITIONS b Transmission is adequate to meet the forecasted peak load and reserves b SRP generation is ready and purchases are adequate to meet the forecasted year 2000 demand b Emergency plans are in place to handle contingency events

5/17/2000Summer Preparedness John Coggins Manager Supply and Trading

5/17/2000Summer Preparedness OPERATING RESERVES b Protect Against Loss of Generation or Transmission Resources Used to Deliver Energy to Firm Load b Targeted Reserve Levels Based on: Amount of Firm LoadAmount of Firm Load Largest Single HazardLargest Single Hazard

5/17/2000Summer Preparedness SUMMER 2000 RESERVES Jun JulAugSep Load (MW) Actual Reserves* Reserves Inside Valley Outside Valley * Meets WSCC and NERC Criteria Meets Southwest Reserve Sharing Group Criteria Meets Southwest Reserve Sharing Group Criteria

5/17/2000Summer Preparedness WW LB KY/SK MD NV PP FC/CR/HY CO SRP Distribution Territory Valley Reserves 209 MW Available Import Capability 0 MW ALL UNITS ON LINE - JULY PV Outside Valley Reserves 427 MW

5/17/2000Summer Preparedness RESULT Peak Load Day (5084 MW) in July b Outside Valley Recovery –Full Recovery From Loss of Largest Generating Unit and and –Full Recovery From Loss of Unit Less Than 245 MW b Inside Valley Recovery –Full Recovery From Loss of Largest Generating Unit and and –Full Recovery From Loss of Unit Less Than 28 MW

5/17/2000Summer Preparedness COORDINATING VALLEY UNIT COMMITMENT APSMerchantSRPMerchant SRPCAOAPSCAO

5/17/2000Summer Preparedness GLEN CANYON LOW FLOW TESTING b Test Flows Implemented May - September Result of 1994 Biological Opinion by USF&WSResult of 1994 Biological Opinion by USF&WS Requires Low Steady Flow At 8,000 cfs June - SeptRequires Low Steady Flow At 8,000 cfs June - Sept b Reduces Plant Output by Several Hundred MW Impacts Market Pricing in the SWImpacts Market Pricing in the SW Impacts Exchange Arrangements with SRPImpacts Exchange Arrangements with SRP

5/17/2000Summer Preparedness GLEN CANYON LOW FLOW TESTING b Emergency Exception Criteria In Effect Activation Requires System Wide EmergencyActivation Requires System Wide Emergency b Testing May Be Abandoned Due to Hydrology

5/17/2000Summer Preparedness SRP TRANSMISSION AND DISTRIBUTION SYSTEM READINESS Dave Areghini

5/17/2000Summer Preparedness SYSTEM IMPROVEMENTS b Items Increasing Import Capability Knox 230kV receiving station andKnox 230kV receiving station and 1-230/69 transformer Four 46 MVAR 69kV capacitor banks at Brandow,Four 46 MVAR 69kV capacitor banks at Brandow, Papago Buttes, White Tanks and Knox REKONDZI: Most of the items you have listed help the subtransmission system but I believe only Item 1 (Knox xfmr) & Item 2 (69kV caps) help the transmission system. The 69kV capacitors are the main reason the lower portion of the load serving nomogram has increased from last year. Item 4, SI/GF monitor did not provide any increase in capacity like the WW/AF monitor did. There are some significant maintenance replacement items, relay improvements, WSCC uniform off frequency load shedding, and 500/ /69 Transformer re-ratings that also contribute to increased load serving capability REKONDZI: Most of the items you have listed help the subtransmission system but I believe only Item 1 (Knox xfmr) & Item 2 (69kV caps) help the transmission system. The 69kV capacitors are the main reason the lower portion of the load serving nomogram has increased from last year. Item 4, SI/GF monitor did not provide any increase in capacity like the WW/AF monitor did. There are some significant maintenance replacement items, relay improvements, WSCC uniform off frequency load shedding, and 500/ /69 Transformer re-ratings that also contribute to increased load serving capability

5/17/2000Summer Preparedness SYSTEM IMPROVEMENTS b Items Serving Increasing Distribution Load 2 nd Ward 230/69kV transformer2 nd Ward 230/69kV transformer Multiple line upgradesMultiple line upgrades REKONDZI: Most of the items you have listed help the subtransmission system but I believe only Item 1 (Knox xfmr) & Item 2 (69kV caps) help the transmission system. The 69kV capacitors are the main reason the lower portion of the load serving nomogram has increased from last year. Item 4, SI/GF monitor did not provide any increase in capacity like the WW/AF monitor did. There are some significant maintenance replacement items, relay improvements, WSCC uniform off frequency load shedding, and 500/ /69 Transformer re-ratings that also contribute to increased load serving capability REKONDZI: Most of the items you have listed help the subtransmission system but I believe only Item 1 (Knox xfmr) & Item 2 (69kV caps) help the transmission system. The 69kV capacitors are the main reason the lower portion of the load serving nomogram has increased from last year. Item 4, SI/GF monitor did not provide any increase in capacity like the WW/AF monitor did. There are some significant maintenance replacement items, relay improvements, WSCC uniform off frequency load shedding, and 500/ /69 Transformer re-ratings that also contribute to increased load serving capability

5/17/2000Summer Preparedness Load Serving Capacity N-0 Continuous & Emergency Limit 5339 MW N-1 Continuous & Emergency Limit 5229 MW Forecasted Base Peak 4970 MW Forecasted Upper Peak 5084 MW

5/17/2000Summer Preparedness SYSTEM PREPARATION Major Line PatrolsMajor Line Patrols Preventative MaintenancePreventative Maintenance Pole WorkPole Work Personnel TrainingPersonnel Training Tree Trimming Cable Replacement Storm Plan Summer Substation and Line Maintenance Complete

5/17/2000Summer Preparedness EMERGENCY OPERATIONS AND LOAD SHEDDING b System Normal b Capacity Critical b Capacity Emergency b Pre-load Shedding b Rotating Blackouts

5/17/2000Summer Preparedness CAPACITY CRITICAL b Potential for Operating Reserve Deficiency if a Major Resource is Lost b Warning Issued to All Plants

5/17/2000Summer Preparedness CAPACITY EMERGENCY b Potential for loss of load if a major resource is lost (reserves are depleted) b Staff unmanned hydro units b Stop maintenance that could jeopardize unit availability

5/17/2000Summer Preparedness CAPACITY EMERGENCY b Prepare to: Cut wholesale salesCut wholesale sales Utilize emergency generation, reduce auxiliary loadsUtilize emergency generation, reduce auxiliary loads

5/17/2000Summer Preparedness ROTATING BLACKOUTS b Predetermined program has already protected critical loads such as hospitals b Load shedding program curtails delivery of power to retail customers

5/17/2000Summer Preparedness

5/17/2000Summer Preparedness SUMMARY OF YEAR 2000 PROJECTED CONDITIONS b Transmission is adequate to meet the forecasted peak load and reserves b SRP generation is ready and purchases are adequate to meet the forecasted year 2000 demand b Emergency plans are in place to handle contingency events

5/17/2000Summer Preparedness

5/17/2000Summer Preparedness

5/17/2000Summer Preparedness