1. Genesys Model Enhancements October 4, 2011 NW Resource Adequacy Steering Committee Meeting Gwendolyn S Shearer

2. Summary of Model Changes Hourly Loads & Wind Slice Logic Operating Year Changed Hydro Shaping Borrowed Hydro Purchases Thermal Commitment Transmission losses New Outputs Gwendolyn S Shearer

3. Hourly Loads & Wind Change Changed to random draws from temperature years for loads and wind years for wind Wind is modeled as a nameplate capacity at a site and wind capacity factors by hour Draws can be random, sequential, or lockstep with water condition Wind is a load reduction resource Gwendolyn S Shearer

4. Hourly Loads Gwendolyn S Shearer

5. Hourly Wind Gwendolyn S Shearer

6. Slice Logic – Fed Only Can now model BPA’s system separate from rest of PNW because of slice logic Slice logic mimics BPA’s contractual obligation to Slice customers User specifies which resources are sliced or not sliced Amount of generation going to sliced customers calculated Gwendolyn S Shearer

7. Hydro Shaping Improved Look ahead decision-making improved Day average hydro shaped to meet hourly load improved Hourly hydro logic improved to better meet load Gwendolyn S Shearer

8. Hydro Shaping Gwendolyn S Shearer

9. Borrowed Hydro Option Borrowed Hydro is hydro that is below firm rights and can be used under certain conditions, specified by the user Measure of when borrowing hydro improved Gwendolyn S Shearer

10. Borrowed Hydro Gwendolyn S Shearer

11. Purchase Options Spot market purchases are available in all hours specified by the user at a given price Purchase ahead resources are available looking ahead two days Gwendolyn S Shearer

12. Thermal Logic Option Coal can be modeled as must run for a day (important for overgeneration spill calculation) Gwendolyn S Shearer

13. Possible Future Improvements Thermal commitment logic Treaty Storage Regulation Better shaping of hydro within month Incorporate LOLP calculation within model Gwendolyn S Shearer