1. Capacity Analysis in the Sixth Plan
GRAC Meeting May 6, 2009

2. Capacity Standard Surplus Sustained Peaking Reserve Margin
The sustained peak generating capability of firm (and some non-firm) resources should equal the sustained peak load plus a surplus derived from the LOLP analysis.
The minimum threshold is derived from an analysis that yields a 5% loss-of-load probability for capacity events.

3. Capacity Standard Surplus Sustained Peaking Capability
Peak Duration Load
Averaged over the peak duration hours – highest load hours/day over 3 consecutive weekdays
Based on normal weather
Includes net interregional firm contracts

4. Capacity Metric For illustration only
Generation values in table are the 6 and 10 highest – assume highest generation placed into appropriate hours
Pink hours are the six highest load hours
Peak limited defined by difference between Max Gen and Peak Load hour
Actual generation not necessarily the most generation that we really could have shaped into peak hours
Rather, this is intended to show the impact of the different metrics with this particular generation profile

5. Capacity Metric
Consideration of applying Peak Limit to something different than Max Gen during fish passage season
Achieving Max Gen may have been possible, but it would have required emptying of LSN/LCOL ponds
Illustration of the importance of energy-limited capacity
Note large value of Peak Limit. Is this why NWPP perceived no problem

6. Capacity Standard Surplus Sustained Peaking Capability
Resources – Averaged over the peak duration
Uncommitted in-region IPP generation
Winter – all available
Summer – 1000 MW
Hydroelectric – Critical year for winter and summer
Wind – 5 percent of nameplate
Out-of-region market supply
Winter – 3000 MW
Summer – Zero
Hydro Flexibility
Winter – 2000 MW

7. Estimating Sustained Hydro Capacity (6-hour duration)
Illustrative Only

10. DRAFT – Under Review

11. DRAFT – Under Review