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

2. Western Electricity Coordinating Council
Overview
Study Program
Study Program scope
Observations
Study Program
Study Program approach
Initial themes for consideration
Western Electricity Coordinating Council

3. 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

4. 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

5. 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

6. 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

7. 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

8. 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 year horizon
Needed for flexibility and reliability goals
Potential need for market-based incentives
Western Electricity Coordinating Council

9. 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

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

11. 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

12. 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

13. 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

14. 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

15. 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 years?
Western Electricity Coordinating Council

16. 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
Western Electricity Coordinating Council

17. 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

18. 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

19. Contact Information
Byron Woertz Manager—System Adequacy (801)
Western Electricity Coordinating Council