1. Modeling the Hydroelectric System in GENESYS Resource Adequacy Forum Technical Committee Meeting July 25, 2007

2. 2 Outline Monthly Hydro Simulation GENESYS Overview Monthly Hydro Dispatch in GENESYS Hourly Hydro Dispatch in GENESYS

3. 3 Rule Curves Minimum Content Maximum Content

4. 4 Desired generation provided manually or by GENESYS For each month

5. 5 Genesys Overview For each game For each year Select random variables For each hour For each month Water year Temperature Forced Outage Get hydro capacity limits Adjust hydro block sizes Build resource stack Get hourly load Do hourly dispatch Get hydro block sizes Build resource stack Build load stack Do monthly dispatch

6. 6 Value of Water in Storage

7. 7 Pricing of Hydro Blocks Hydro BlockRelative Resource Relative Price Flood ControlNuclear Assured refillBeaver Actual energy reg.Fredonia10 Critical rule curveFredonia11 EmergencySW SCCT10

8. 8 Hydro Flexibility (Emergency Only) Additional hydro generation gained by relaxing some operating constraints Draft below critical rule curve Allow spill at upstream dams Draft below fish refill curves Does not violate Coulee rate-of-draft Keeps about 5,000 MW-months in system Highest cost resource (priced higher than out-of-region spot market) = Last resource dispatched

9. 9 Hydro Capacity vs. Monthly Energy December

10. 10 Hydro Capacity vs. Duration

11. 11 Guidelines for Hydro Dispatch Any single hour < 1-hour capacity 2 consecutive hours < 2-hour capacity 4 consecutive hours < 4-hour capacity 6 consecutive hours < 6-hour capacity 8 consecutive hours < 8-hour capacity 10 consecutive hours < 10-hour capacity 12 consecutive hours < 12-hour capacity

12. 12 Sample Hourly Dispatch in Genesys