SRP Summer Preparedness 2001 and 2002

1. SRPSummer Preparedness2001 and 2002 Presented to the Arizona Corporation Commission February 16, 2001 ACC Energy Workshop – Summer Preparedness 2001 and 2002

2. David Areghini Associate General ManagerPower, Construction & EngineeringServices ACC Energy Workshop – Summer Preparedness 2001 and 2002

3. Agenda • SRP system & load growth • Summary of year 2001 and 2002projected readiness • Resources and reserves • SRP system readiness ACC Energy Workshop – Summer Preparedness 2001 and 2002

4. SRP Electric Service Territory Peoria Scottsdale Surprise Phoenix FountainHills ParadiseValley Eastern Mining Area LitchfieldPark Glendale Tolleson Mesa ApacheJunction Tempe Gilbert Avondale Chandler QueenCreek Goodyear ACC Energy Workshop – Summer Preparedness 2001 and 2002

5. Expected Load Growth Peoria Surprise Youngtown FountainHills Phoenix Scottsdale ParadiseValley LitchfieldPark Glendale Tolleson Mesa 4.5% 2.7% ApacheJunction Tempe 18% 4.2% Gilbert Avondale 3.8% Chandler QueenCreek Goodyear ACC Energy Workshop – Summer Preparedness 2001 and 2002

6. Summary of Year 2001 and 2002 Projected Conditions • Transmission, SRP generation and planned energy purchases areadequate to serve the forecastedyear 2001 and 2002 demand • Contingency plans are in place tohandle emergency events ACC Energy Workshop – Summer Preparedness 2001 and 2002

7. John Coggins Manager Supply and Trading ACC Energy Workshop – Summer Preparedness 2001 and 2002

8. Operating Reserves • Protect against loss of generationor transmission resources usedto deliver energy to firm load • Targeted reserve levels based on: • Amount of firm load • Largest single hazard ACC Energy Workshop – Summer Preparedness 2001 and 2002

9. 2001 System Reserves ACC Energy Workshop – Summer Preparedness 2001 and 2002

10. Summer 2001 Reserves Jun Jul Aug Sep Load (MW) Actual reserves* Reserves Valley Stranded 4980 627 6270 5330 635 421214 5330 636 421215 4840 841 8410 * Meets WSCC and NERC Criteria Meets Southwest Reserve Sharing Group Criteria ACC Energy Workshop – Summer Preparedness 2001 and 2002

11. Valley Reserve Shortfall – August 2001 Navajo Four Corners/Craig/Hayden Mead Outside ValleyReserves 215 MW SRP Distribution Territory West Wing Pinnacle Peak Valley Reserves421 MW Available Import Capability 0 MW Coronado Liberty Palo Verde Kyrene/Browning/Silverking ACC Energy Workshop – Summer Preparedness 2001 and 2002

12. SRP Resources - 2001 Total 5966 MW Purchased Power Reserves 636 MW 1902 MW SRP Forecast Peak Load SRP Owned Generation 5330 MW 4064 MW

13. SRP Owned Generation – 2001(Capacity) Total 4064 MW Hydro 229 MW Oil & Gas1260 MW Coal1915 MW Nuclear 660 MW ACC Energy Workshop – Summer Preparedness 2001 and 2002

14. Fuel Status • Nuclear – Full requirements under contract • Coal • All plants currently at or above target inventories • Full requirements under contract • Natural gas • Full transportation requirements under contract • Retail commodity requirements secured • Pipeline curtailments anticipated • Fuel oil back-up ACC Energy Workshop – Summer Preparedness 2001 and 2002

15. Fuel Status • Fuel Oil • Critical back-up for natural gas • Allows plants to continue tooperate during gas curtailments • Increasing inventory levels tomeet anticipated requirements • Adequate storage capability ACC Energy Workshop – Summer Preparedness 2001 and 2002

16. 2002 System Reserves ACC Energy Workshop – Summer Preparedness 2001 and 2002

17. Summer 2002 Reserves Jun Jul Aug Sep Load (MW) Actual reserves* Reserves Valley Stranded 5147 831 74982 5530 839 370469 5530 840 510330 4965 841 8410 * Meets WSCC and NERC Criteria Meets Southwest Reserve Sharing Group Criteria ACC Energy Workshop – Summer Preparedness 2001 and 2002

18. SRP Resources - 2002 Total 6370 MW Purchased Power Reserves 840 MW 2166 MW SRP Forecast Peak Load SRP Owned Generation 5530 MW 4204 MW

19. John Underhill ManagerSystem Operations ACC Energy Workshop – Summer Preparedness 2001 and 2002

20. 2001 System Conditions ACC Energy Workshop – Summer Preparedness 2001 and 2002

21. System Improvements 2001 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 500/230 - 230/69 Transformer re-ratings that also contribute to increased load serving capability • Projects increasing import andload serving capability • Browning 500/230kV receiving station • Four 230/69kV transformer additions • Four new residential substations • Six 69/12kV transformer additions • Seven capacitor additions ACC Energy Workshop – Summer Preparedness 2001 and 2002

22. Load Serving Capacity 2001 N-0 Continuous & Emergency Limit 5831 MW N-1 Continuous & Emergency Limit 5553 MW Forecasted Upper Peak 5330 MW Forecasted Base Peak 5210 MW ACC Energy Workshop – Summer Preparedness 2001 and 2002

23. 2002 System Conditions ACC Energy Workshop – Summer Preparedness 2001 and 2002

24. System Improvements 2002 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 500/230 - 230/69 Transformer re-ratings that also contribute to increased load serving capability • Projects increasing import andload serving capability • Kyrene Expansion Project • Four 230/69kV transformer additions • Three new residential substations • Seven 69/12kV transformers • Multiple 230kV & 69kV line upgrades ACC Energy Workshop – Summer Preparedness 2001 and 2002

25. Load Serving Capacity 2002 N-0 Continuous & Emergency Limit 6093 MW N-1 Continuous & Emergency Limit 5803 MW Forecasted Upper Peak 5530 MW Forecasted Base Peak 5410 MW ACC Energy Workshop – Summer Preparedness 2001 and 2002

26. Major line patrols Preventative maintenance Pole work Personnel training Tree trimming Cable replacement Storm plan System Preparation Summer substation and line maintenancewill be complete by summer ACC Energy Workshop – Summer Preparedness 2001 and 2002

27. Emergency Operations and Load Shedding • System Normal • Capacity Critical (Internal) • Capacity Emergency (Stage 1) • Pre-load Shedding (Stage 2) • Rotating Blackouts (Stage 3) ACC Energy Workshop – Summer Preparedness 2001 and 2002

28. Concerns • WSCC curtailments • Existing Kyrene units (2002+) • Energy exchange at Glen Canyon • Double contingencies • Voltage collapse ACC Energy Workshop – Summer Preparedness 2001 and 2002

29. Significant Near Term Major Transmission and Generation Needs Southwest Valley 500kV Transmission Project(Summer 2003) Santan Expansion Project(Summer 2004-2005) ACC Energy Workshop – Summer Preparedness 2001 and 2002

30. Summary Of Year 2001 and 2002 Projected Conditions • Transmission, SRP generation and planned energy purchases areadequate to serve the forecastedyear 2001 and 2002 demand • Contingency plans are in place tohandle emergency events ACC Energy Workshop – Summer Preparedness 2001 and 2002