Byron Woertz, Manager—System Adequacy Planning RAC Study Program Byron Woertz, Manager—System Adequacy Planning Western Electricity Coordinating Council

Western Electricity Coordinating Council Overview 2016-2017 Study Program Study Program scope Observations 2018-2019 Study Program Study Program approach Initial themes for consideration Western Electricity Coordinating Council

2016 Study Program 2026 Common Case Most likely future in 2026 Sensitivity Cases High/Low Loads High/Low Hydro High/Low Gas Price High/Low CO2 Price Special Interest Cases Resource retirements Resource expansion Resource locations Probabilistic study Energy storage Western Electricity Coordinating Council

2017 Study Program—Year 10 Cases 2026 Common Case Most likely future in 2026 Resource Cases High Wind High Solar Transmission Expansion Cases East-to-West NE-to-SW “Transmission Backbone” Special Interest Case Curtailment Prices Probabilistic Study Western Electricity Coordinating Council

2017 Study Program—Year 20 Cases 2034 Reference Case Extension of 2026 Common Case Scenario-Based Cases S2—Focus on Clean Energy S3—Focus on ST Consumer Costs S4—Focus on LT Societal Costs Energy-Water-Climate Change Special Interest Cases High Distributed Energy Resources High Coal Retirements Western Electricity Coordinating Council

Preliminary Observations—Year 10 Studies Transmission Across all studies, grid appears to be adequate Storage Cases Additional storage facilitates additional wind—with limitations Pumped hydro storage can absorb wind fluctuations Gas In high renewable cases, gas varies counter to renewables No consistency in impacts on transmission flows Western Electricity Coordinating Council

Preliminary Observations—Year 20 Studies Renewable Development Increase in renewables requires larger generation portfolio Increased variability increases reserve and flexibility requirements CO2 Cost At $58/ton, all coal present in 2026 is displaced in 2034 Gas resources maintained to meet reliability needs Water consumption and CO2 production decreased by over 50% Energy and Capacity 2026 Common Case resources can satisfy most energy goals Additional resources needed for capacity and seasonal variations in moderate-to-high growth scenarios Higher capacity needed for scenarios with higher renewables or constraints Western Electricity Coordinating Council

Year 20 Observations—Cont. Solar PV preferred over Central Station Power DG carve-outs may be a factor Wind Wind is most economic renewable based on energy production Significant wind additions in New Mexico Potential need for transmission reinforcements may warrant further study Gas Gas generation may not be economically competitive for energy-only in 10-20 year horizon Needed for flexibility and reliability goals Potential need for market-based incentives Western Electricity Coordinating Council

Western Electricity Coordinating Council From Past to Future Tool-Based Approach What can we learn from PCM analyses? What can we learn from power flow analyses? Risk-Based Approach What potential future reliability risks should we be thinking about? How can we study them? Western Electricity Coordinating Council

Drivers for Future Reliability Assessments 2018-2019 Study Program Priority Reliability Issues Board Near-Term Priorities WECC Scenarios Western Electricity Coordinating Council

Reliability Assessment Structure Key Reliability Question Connection to NT Priorities and Scenarios Modeling Options Data Needs Expected Results Resource Requirements Potential Partners Western Electricity Coordinating Council

Potential Reliability Assessment Themes Change in System Inertia What are the reliability impacts of retiring significant thermal resources and increasing penetration of intermittent resources? Achieving GHG Reduction Are renewables the best option to achieve GHG reductions? What CO2 price would be required to achieve GHG reduction targets? Electric Vehicle Market Penetration Do high EV penetration levels (10%? 20%? 50%?) create reliability risks? Western Electricity Coordinating Council

Potential Themes, cont. WECC Scenario 1: Open Market, Restricted Choices What are the reliability impacts of an increasingly diverse resource mix as state and provincial policies become less coordinated? WECC Scenario 2: Open Market, High Choice As distributed resources become significant, what infrastructure changes and upgrades in the BPS and distribution systems might be needed? WECC Scenario 3: High Mandates, Restricted Choices How might the most economically competitive utility-scale power supply resources across the Western Interconnection be identified and paired with the appropriate transmission? Western Electricity Coordinating Council

Potential Themes, cont. WECC Scenario 4: High Mandates, High Choice What are the reliability impacts of retiring significant thermal resources, high solar/wind penetration an no synthetic inertia? WECC Scenario 5: Energy-Water-Climate Change Scenario What potential risks to the reliability of the Bulk Electric System in the Western Interconnection would result through changes to the climate? Reliability Impacts of the Most Likely Year 10 Future In the Year 10 “Base Case” (2028 Anchor Data Set), are there any reliability risks associated with path flows, resource adequacy, system stability or other parameters? Western Electricity Coordinating Council

Potential Themes, cont. Utility Business Models Will alternate utility business model, for example, the development of “prosumagers,” create reliability risks? Resilience What are the reliability impacts of a major disruption in 2020, 2028 and 2038? What corresponding impacts on gas, water, communications or other systems could exacerbate electric system impacts? Significant Increase in Demand What reliability risks could result from a significant increase in demand in the next 10-20 years? Western Electricity Coordinating Council

Potential Themes, cont. Gas-Electric Interface Issues What additional reliability risks might the Western Interconnection experience with high intermittent resource penetration? Water Availability Impacts With projected increases in natural gas generation, will there be sufficient water to operate thermal resources? Resource Adequacy Under Contingency Will there be sufficient resource adequacy if generator outages in 2028 follow historic patterns observed in 2015-2017 Western Electricity Coordinating Council

Potential Themes, cont. Significantly Higher Levels of DER What are the reliability impacts on the bulk power system and associated concerns that would result from significantly higher levels of DER in the Western Interconnection? High Penetration of Electronically-Interfaced Loads How will the increasing penetration of electronically-interfaced end-use loads (e.g., air conditioning, motor loads converted to variable frequency drives (VFDs) affect the reliability of the Western Interconnection? 100% Carbon-Free Energy Supply What are the potential reliability impacts to the Bulk Power System in the Western Interconnection that could result from a 100% carbon-free energy supply? Western Electricity Coordinating Council

2018-2019 Study Program Schedule Dec 2018 Complete Scoping Form Assessment Teams Jan-Sep 2019 Determine modeling approaches Develop data Complete assessments Report on results May-Aug 2019 Review assessment priorities Consider new assessments Oct-Dec 2019 Finalize reporting Western Electricity Coordinating Council

Contact Information Byron Woertz Manager—System Adequacy bwoertz@wecc.biz (801) 883-6841 Western Electricity Coordinating Council