1. January 14, 2016 PacifiCorp-CAISO-NVE EIM Initiative Overview

2. Agenda Introduction PacifiCorp background Real-time operations of EIM Challenges Current status

3. PacifiCorp customers 3 Investor owned utility – subsidiary of Berkshire Hathaway Energy 6,447 staff in U.S. 1.8million customers in 6 states Utah (42%) Oregon (25%) Wyoming (17%) Washington (8%) Idaho (6%) California (2%) PacifiCorp Peak Load:12,558 MW PACW: 4354 MW 80+ Ties with other Balancing Areas PACE: 8989 MW 50+ Ties with other Balancing Areas

4. EIM Footprint PacifiCorp 1.7 million customers 9,500 MW peak demand 10,600 MW generating capacity NV Energy 1.2 million customers 8,148 MW peak demand 5,815 MW generating capacity CAISO 11.4 million customers 50,280 MW peak demand 58,246 MW generating capacity PSE and AZPS Coming soon….

5. EIM Concept What is an EIM – It is not an ISO – It is not balancing our BAA EIM in real-time – Generation redispatch – Forward looking transmission management BAA’s responsibilities – Not changing – New tools and processes

6. Variable Energy Operation

7. EIM Real-Time Operations Timing criticality of a 5 minute system Base Schedules Hourly vs. 15 minute vs. 5 minute markets Dispatches Transmission congestion Outages

8. Operational Concept Overview Expansion of CAISO’s current 5 minute market – Security Constrained Economic Dispatch Transmission constraint management Network model visibility and accuracy Terminology: – Market Operator, EIM Entity, Participating Resources, Manual Dispatch, Instructed/Uninstructed Imbalance charges, Scheduling Coordinator….. Detailed outage reporting and situational awareness

9. Base Schedules Entity must come to the market balanced Base Schedule (G + I = L) (feasibility check) – Forecast of load – Forecast of generation – Forecast of interchange Submitted by all customers to EIM Entity Data aggregated and validated by PacifiCorp Grid Entity retains all BAA responsibilities

10. Base Schedule data flow (via SCs)

11. Balance and Feasibility Tests Base Schedule Balancing Test Bid Range Capacity Test Flex Ramp Required Sufficiency Test Transmission Feasibility Test

12. Hourly vs. 15 minute vs. 5 minute Hourly market (HASP) – Unit start up, shut down, and transitions 15 minute market (RTPD) – Market awards, e-tags – Runs approx. 40 minutes ahead 5 minute market (RTD) – Dispatches based on 15 min awards – Runs approx. 7.5 minutes before ramp

13. Dispatch Dispatch sent to PacifiCorp’s Ranger (EMS), to RTU, and to the plant

15. Transmission Congestion Forward looking congestion management 15 minute market awards published for 8+ intervals Correcting limits in state estimator Collaboration between Energy Grid Operator (EIM desk) and TO desks

16. Outage Reporting Requirements Outage reporting is critical to SE and dispatches Planned outages must be submitted at least 7 days in advance – For EIM, at least seven days Forced outages must be reported within 30 minutes – Less imbalance the sooner it is reported PAC using COMPASS to interface to CAISO’s OMS Market run criticality

17. PAC and CAISO responsibilities PAC retains all reliability function responsibility PAC will balance their ACE, manage reserves (no impact to NWPP RSG) and manage their voltage Under EIM, CAISO operates the market and publishes market results for both PAC and CAISO (the EIM footprint) Under EIM, PAC will operate transmission, monitor generation, process outages, and balance ACE for PACW and PACE

18. Challenges (go-live) Go-live Typical IT software refining Accuracy of generation unit outages and derates for informing market Disciplined generation and interchange resource plan that aligns with market Network model accuracy Change management Updates System accuracy increasing Reaching granular aspects of base scheduling Network model aligned with CAISO and updated monthly Evolution of change management – (ongoing but evolving)

19. Challenges (current) Change management evolution – Understanding market actions Outage management tools upgrades – New webOMS system Seasonal strategies – Fuel restrictions NVE incorporation – New dynamic transfers – Networks the BAAs, rather than radial

20. Current Status Continue updates of network model Available Balancing Capacity testing – January Continued focus on transmission constraints Solar integration

21. Questions John Schaffroth (503) 251-5154 john.schaffroth@pacificorp.com