Planning Tools Overview Modeling Subcommittee Chifong Thomas November 30, 2017 Western Electricity Coordinating Council

Western Electricity Coordinating Council Topics Purposes of this Discussion Planning Objectives Planning Processes Modeling Challenges Load Resources Network Next Steps Western Electricity Coordinating Council

Western Electricity Coordinating Council Purposes Develop a forum to further understanding and future coordination of issues relating to the Planning tools Identify similarities and differences Discuss potential issues and resolutions Set up on-going discussions Western Electricity Coordinating Council

Basic Planning Questions Do we have enough resources to economically serve the forecasted load over all time periods? Can we deliver the forecasted resources to the individual loads under reasonably adverse conditions? Western Electricity Coordinating Council

Western Electricity Coordinating Council Planning Questions Types, locations, and sizes of future resources? Types, locations and sizes of future loads? Credible future network? New technologies? Criteria for acceptable performance? Others? Western Electricity Coordinating Council

Resource Planning & Transmission Planning Processes Load Forecast Policy Multi-step iterative process to ensure that Loads can be reliably and economically served Western Electricity Coordinating Council

Processes for Resource Planning and Transmission Planning Resources by technology and location Aggregated Load + estimated losses Resources by Technology Loads by Substation bus Generator Production costs Aggregated Imports/Exports Network Topology Import, Export Typical Production Simulation Models Typical Power flow/ Stability Models Bridge Needed Power Flows on Facilities Reliability Indices Marginal Costs losses Expected Portfolio Production Costs Bus voltages Over a Period of Time/ Very Limited Network Single Point in Time/ Detailed Network Analyses

Western Electricity Coordinating Council Bridge Add network to the PCM Simulation For the selected operating point, add resource dispatch pattern to the power flow simulation Others? Western Electricity Coordinating Council

Primary Planning Tools Production Simulation (Production Cost Modeling) Power Flow (Steady State) Simulation Stability (Dynamic) Simulation Programs are Complementary Consistent ≠ Identical Western Electricity Coordinating Council

Discussion: Examples of Modeling Questions Loads: Are the system conditions for a point on the 1 in 2 load forecast curve the same as the corresponding point on the 1 in 5 load forecast curve? Should Behind the meter resource be modeled as a generator or a negative Load? Should Energy Efficiency be modeled as peak shaving, same % load reduction for all hours, etc.? Should Demand Response be modeled based on existing programs? How are future programs incorporated? Western Electricity Coordinating Council

Discussion: Examples of Modeling Questions How much of the composite load model needed to be reflected in the PCM? Is there a connection between the load compositions (Constant power, constant current and constant impedance) in the Power flow/Stability and load profiles in the PCM? Load power factors at different load levels – impacts power flow/stability; but probably no impact on PCM Others? Western Electricity Coordinating Council

Examples of Modeling Questions Resources: Fictitious resources? Locations? Retirements? Dispatchable? Must-take? Fixed generation profile? Hydros Renewables LCR/RMR? What does optimization mean if we have too many must-take resources? Western Electricity Coordinating Council

Discussion: Examples of Modeling Questions Unit commitment – number of units on line at a plant can impact power flow/stability but may not impact PCM results Voltage ride through capabilities Frequency Ride through capabilities Generator models – governor response, droop setting, Power System Stabilizer, Reactive capabilities Others? Western Electricity Coordinating Council

Discussion: Examples of Modeling Questions Transmission Network: How would we model path limitations? Fictitious elements? Which new transmission facilities to include: Approved facilities only? Also planned (but not approved) facilities? Other transmission facilities associated with potential generation addition? RAS/SPS? Others? Western Electricity Coordinating Council

Western Electricity Coordinating Council Next Steps Identify and prioritize Issues Are there existing models that should be tested? On-going discussion Western Electricity Coordinating Council