Dan Beckstead Associate Staff Engineer

1. Dan BecksteadAssociate Staff Engineer TEPPC 2024 Common Case Load

2. 2024 TEPPC Common Case – Major Assumptions

3. 2024 TEPPC Common Case – Load Assumptions

4. Dataset Building Activities LRS Submittals Utility IRPs Resource Planners DSM Task Force LRS Submittals SCG Common Case Transmission Assumptions WREZ Tool Work Group Participants Loads DWG WECC Powerflow Case NREL Meso-scale Data Resource Portfolio SWG Transmission Network SWG Data Improvements DWG Modeling Enhancements MWG WECC Staff TEPPC Dataset Debugging/Validation DWG/MWG/SWG/Staff WECC Staff Scenario Runs/Analysis/Reporting

5. Balancing Authority Load Forecasts • Provided to WECC by the BAs and forwarded to NERC and FERC as required under the FERC-approved NERC Standards • Brings together the Load Serving Entities (LSEs) forecasts inside each respective BA • LSEs within each BA provide the BA with their load forecast, who in turn provides the BA forecast to WECC’s Loads and Resources Subcommittee (LRS) each year

6. Balancing Authority Load Forecasts • 10-year forecast • 1-in-2 (50% or median) forecast • Specified on an annual and monthly energy (GWh) and peak (MW) basis • 2010 BA forecasts provided a starting point for the 2022 TEPPC Common Case

7. TEPPC Load Bubbles

8. Steps: (DWG input required) • Collect LRS Submittals • Submit BA forecast to LBNL • LBNL to apply EE adjustments • Adjusted 2024 peak and energy forecasts applied to 2005 historic hourly shapes • Check Load shape distortion (Compression/Expansion) • Apply Pumping Loads

9. Excessive Compression of the shape Cause: The forecasted growth in energy is a lot greater than the forecasted growth in peak for a particular month. There will be a noticeable amount of compression in the forecasted shape for a month when the monthly load factor of the forecast is a lot greater than the monthly load factor of the existing shape. Consequences: The change in the loads between peak and off-peak hours is reduced which decreases the amount of variation in the loads. Excessive compression of the shape also tends to diminish the features of the shape such as the difference in the daily peak values between weekend days and weekdays. When a shape is compressed to the extreme it becomes a flat line with no variation or features.

11. Excessive Expansion of the shape Cause: The forecasted growth in peak is a lot greater than the forecasted growth in energy for a particular month. There will be a noticeable amount of stretching in the forecasted shape for a month when the monthly load factor of the forecast is a lot less than the monthly load factor of the existing shape. Consequences: The change in the loads between peak and off-peak hours is increased which increases the amount of variation in the loads. Excessive stretching of the shape also tends to exaggerate the features of the shape such as the monthly peaks or the difference in the daily peak values between weekend days and weekdays.

13. Pumping Loads: • 2005 Pumping loads in 2022 dataset • Actual pump loads are available for use in the 2024 dataset • Options: • Use loads from a certain year (2005 as per DWG discussion on March 26th) • Use average for several years/ scale to match peak load or total energy

14. Pumping Loads: • Does TEPPC want to change pumping loads in Hydro Sensitivity cases? • 2011 High Hydro Year • 2001 Low Hydro Year

15. Questions? Dan Beckstead Associate Staff Engineer Western Electricity Coordinating Council dbeckstead@wecc.biz (801) 819-7656