1. Use of EDWG Data by the LTPT WECC Staff January 15, 2016 W ESTERN E LECTRICITY C OORDINATING C OUNCIL

2. What is the LTPT? The LTPT - Long Term Planning Tool: Is a capital expansion tool 20 year study horizon Evaluating potential energy future 2 W ESTERN E LECTRICITY C OORDINATING C OUNCIL

3. LTPT LTPT comprised of: – SCDT-Study Case Development Tool – NXT-Network Expansion Tool 3 W ESTERN E LECTRICITY C OORDINATING C OUNCIL

4. SCDT SCDT - Study Case Development Tool – Produce Study Case – Optimized study case representing potential “energy future” – Comprised of reduced nodal network model – Transmission expansion candidate lines – Transmission capital cost – Minimum cost generation optimization-decision factors, constraints 4 W ESTERN E LECTRICITY C OORDINATING C OUNCIL

5. NXT NXT - Network Expansion Tool – Relieves candidate lines for four system conditions Heavy Summer, Light Spring, Light Fall, Heavy Winter, oveloaded, loss of load etc – Optimized transmission network expansion – Mitigating engineering constraints – Grid cost components applicable to study case 5 W ESTERN E LECTRICITY C OORDINATING C OUNCIL

6. LTPT Process Workflow 6 W ESTERN E LECTRICITY C OORDINATING C OUNCIL Perform Modeling No Yes Define Scenarios to be examined in narrative Parameterize Scenarios / Sensitivities Does Parameteriz ation affect Scenario narrative? Are results reasonable? No Yes Select ‘no regrets’ investments; decide other recommendations Compare Scenario results based on pre- determined Metrics Are sensitivities of Scenarios required? Yes No Define Metrics to be used to evaluate Scenario/Sensitivity results

7. 10-Year & 20-Year Planning Comparison Attribute10-Year Studies20-Year Studies ToolProduction Cost ModelCapital Expansion Model Objective MinimizationProduction CostCapital Cost FocusCapacity additions and specific projects, planned and in progress Understanding potential “energy futures” and decisions needed to achieve those futures Model decides toDispatch GenerationBuild Gen and Transmission LoadFrom balancing authorities w/ stakeholder adjustment ResourcesStakeholder specificStakeholder specific and LTPT optimized TransmissionStakeholder specificStakeholder specific and LTPT optimized Time GranularityHourly / Sub-hourlyAnnual / Seasonal Load Durations InterdependenceStarting point of 20-YearInforms 10-Year W ESTERN E LECTRICITY C OORDINATING C OUNCIL 7

8. EDWG Data in LTPT – Transmission route finding input – No Siting – More realistic cost estimate – Environmental Risk – Line weighting-Financial Element 8 W ESTERN E LECTRICITY C OORDINATING C OUNCIL

9. Risk Weightings EDWG Risk Category Weightings – Think of the weighting similar to miles 9 W ESTERN E LECTRICITY C OORDINATING C OUNCIL

10. Staying in the fairway. Avoiding hazards. Minimizing strokes. Traversing the geospatial landscape

11. W ESTERN E LECTRICITY C OORDINATING C OUNCIL 11 Overlay EDWG and Transmission Candidate Cooridors

12. Build cost surfaces Bend corridor routing to minimize environmental impact. Optimize Corridors W ESTERN E LECTRICITY C OORDINATING C OUNCIL 12

13. Transmission Models and Assumptions Start with TEPPC 2024 Power Flow Model Delineate load and generation hubs. Perform Network Reduction, preserving interface and CCTA transmission lines. Define aggregation zones delineated by WECC Paths. Define list of monitored lines based on aggregation zones. Define transmission technology types and characteristics. Define list of candidate corridors based on tiered rules. Optimize corridor routing W ESTERN E LECTRICITY C OORDINATING C OUNCIL 13

14. Economic Models and Assumptions Fuel Prices – Henry Hub per EIA Annual Energy Outlook (converted to 2014 dollars) – Differentials by state – Progress multipliers per E3 Capital Cost Tool/Report Resource Types & Costs – Capital Cost: E3 Capital Cost Tool (“E3 Tool”), TEPPC approved – Future types & Progress multipliers - 2027 Vintage per E3 Tool – Simplified LCOE Model - E3 Tool Policy – CO2 Price: $37.11/MT Per stakeholder input – Metric Definition Task Force (MDTF) – No PTC, Solar ITC reduced to 10% Per E3 forecast of federal policy – Coal constraints per stakeholder input EIA – U.S. Energy Information Administration AEO – Annual Energy Outlook DG – Distributed Generation RPS – Renewable Portfolio Standard NREL – National Renewable Energy Laboratory Transmission Costs o Per TEPPC Capital Cost Update: B&V analysis/report and tool, with stakeholder review/approval o Includes Transmission and Substation Costs o Cost Factors Include: EquipmentTerrain ROWAFUDC BreakersTransformers VoltageCompensation o LCOE per E3 “levelization calculation” (E3 Captial Cost Tool) PTC – Production Tax Credit ITC – Investment Tax Credit W ESTERN E LECTRICITY C OORDINATING C OUNCIL 14

15. Focus on Inter-regional needs 15 W ESTERN E LECTRICITY C OORDINATING C OUNCIL

16. Tool Enhancements Introduction of Corridor Library Parameterized Goals Parameterized Constraints Co-optimization across seasonal and load level conditions Improved reduced network model 16 W ESTERN E LECTRICITY C OORDINATING C OUNCIL