Emerging Technologies Integration in ERCOT

1. Emerging Technologies Integration in ERCOT 2012 ERCOT Operations Seminar Mark Bruce Principal Stratus Energy Group

2. Introduction The recent regulatory paradigm shift to an open access common carrier network system coupled with a variety of economic, environmental, and policy factors have led to significant and widespread investment in an array of new technologies which offer substantial opportunities but also pose fundamental challenges to the planning and operation of the ERCOT bulk electric system.

3. Objectives • At the completion of this course of instruction you will: • Recognize an array of emerging technologies currently in various stages of market entry on the ERCOT system • Understand the high-level opportunities and challenges such technologies pose for the ERCOT system from the planning and operations perspectives

4. Technologies Surveyed • Wind • Solar • Compressed Air Energy Storage • Battery storage • Demand response • Distributed generation • Future technologies

5. System Challenges • Load Forecasting • Generation Scheduling • Ancillary Services Procurement/Dispatch • Primary Frequency Response • System Inertia • Network Model and Planning Models • Interoperability and Integration

6. Emerging Technology Drivers • Public Policy • Private and Public Investment • Technical Challenges • Technological Advances • Environmental Considerations • Economic Factors

7. Wind: capacity growth

8. Wind: energy growth Cumulative wind energy in ERCOT – Jan. 2008-June 2009

9. Wind: dispatch • The evolution of wind energy dispatch • Early Zonal: Wind scheduled and dispatched by QSEs who accounted for wind in SCE. • Late Zonal: Wind scheduled and dispatched by QSEs and ERCOT offset wind SCE through BES adjustments immediately prior to operating interval. • Nodal: WGR base point set by SCED equal to HSL which is equal to WGRPP minus curtailment.

10. Wind: forecasting • Evolution of wind forecasting in ERCOT • QSEs used own forecasting methodologies with widely varying accuracies. • Bifurcation of DA and RT forecasts • DA models and RT persistence • Development of independent ERCOT forecast • Nodal: Single, independent forecast which integrates historical data, forecasted performance, and RT site-specific telemetry.

11. Wind: forecasting

12. Wind: technical standards • The technical requirements for WGRs have evolved over time in ERCOT. • Voltage Ride-Through • Reactive Power Capability • Ramp rate limitations • Performance Metrics

13. Responsive Reserve Deployed 243 MW decrease in 14 sec source: ERCOT

14. Wind: CREZ implementation

15. Wind: market impacts • Price impacts • PTCs weigh on LMPs • Forward markets • Bilateral market • Some element of RT volatility • Long term resource adequacy impacts

16. Wind: multiple profiles • West, North, South/Coastal

17. Wind: limits to DG wind growth • Land use / zoning • Scale / capacity factor • Geography / wind profile • Cost to benefit ratio • Technology limitations relative to others

18. Wind: remaining challenges • WGR modeling • WGR planning horizon • HA forecasting / RT awareness • Net Load swings

19. Solar: different technologies • PV • Concentrating • Thermal hydraulic • Thermal storage • Inverter technologies • Associated turbine technologies

20. Solar: opportunities • PTCs and ITCs weigh on LMPs • Greater coincidence with peak demand

21. Solar: system issues • Similar to wind • Modeling • Performance metrics • Forecasting • Inertia • Solar DG is under the radar

22. Energy Storage: technologies • CAES • Batteries • Flywheels • Pumped hydro • Thermal mass

23. Energy Storage: CAES

24. Energy Storage: batteries • Various battery types • Applications range from tens of MW to small kW capacities. • Typically of limited duration • Typically have need to cycle to some significant depth of discharge

25. Energy Storage: rules matter • Is it a generator, a load, or a transmission or distribution system device? Yes. • Presidio NaS battery treatment • SB 963, 82nd Texas Legislature • PUCT Rules • ERCOT Protocols and OBDs

26. Energy Storage: specs • Very different technologies have very different capabilities as generation resources and as load resources • Likely to have very different roles in the market and, therefore, in system operations

27. Flywheel Regulation Example A fossil plant following a regulation command signal Energy Storage accurately following a regulation command signal

28. Demand response • Small customer-owned systems • Larger, more complex DR aggregations • DR as defined market services • Storage as DR • HAN-enabled devices • RT price awareness • Load forecast impacts

29. Hot day, high A/C load 21,000 MW of residential summer peak load • Both days were Wednesdays • Customer class breakdown is for competitive choice areas only • IDR meters are required at >700kW Residential Moderate day, low A/C load Large C&I ERCOT load for this hour: 63,594 MW ERCOT load for this hour: 30,697 MW

30. Distributed Generation • Limits to wind DG growth • Accelerating solar DG growth • Steady UPS systems growth • Lack of holistic DG awareness

31. Future Applied Technologies? • Electric Vehicles (EVs) • Wide-scale RT price-sensitivity coupled with demand elasticity • Ubiquitous thin-film solar applications • Mass commercial import/export capability

32. Summary • An array of emerging generation, storage, and demand response technologies present both opportunities and challenges to the ERCOT system. • Capturing benefits while mitigating risks requires awareness and flexibility.

33. Questions ? ?