Enhanced Curtailment Calculator (ECC) Jeremy West Sr. Operations Engineer

Learning Objectives History behind need for ECC Review ECC proposed functionality ECC interactions with scheduling

The Evolution of SOLs/IROLs in the West Prior to 2011: No IROLs identified in the West RC and TOPs primarily focused on Major WECC Transfer Paths Equipment/Facility ratings not considered SOLs April 2012 – RC SOL Methodology revised SOLs – facility ratings, bus voltage and stability limits IROLs – process for identification August 2013 – RC SOL Methodology second revision Improve processes for determining IROLs Greater emphasis on determining acceptable pre- and post- Contingency operating conditions

Enhanced Curtailment Calculator (ECC) A reliability tool that Peak RC can use in conjunction with its other tools to ensure acceptable system performance What is the ECC? Phase I – Situational awareness Phase II – Enhanced curtailment / redispatch How will the ECC be implemented?

Enhanced Curtailment Calculator (ECC) What issues does ECC address? webSAS Limitations UFMP restricted to 6 Qualified Paths TDFs based on seasonal models Increased system awareness Visibility of untagged flows Incorporation of outage info (gen and trans) Compliance Address IRO and TOP standards Address September 8 event recommendations

ECC Phase I Provides situational awareness to RC Current hour – uses SE for topology Look ahead hours – starts with SE topology but adds generator and transmission outage data Visualizes “layers” of impacts e-Tags Market Flows Dynamic Transfers ACE / RBC Flows Network & Native Load RSG Flows

ECC Phase II Implementation of FERC-approved curtailment methodology Transition from webSAS to ECC for support of UFMP on 6 Qualified Paths Redispatch and curtailment to manage congestion on defined elements as needed to support reliability Collaborative effort with entities when implemented

ECC Interactions with Scheduling e-Tagging Source/Sink Granularity BA A BA A BA B BA B = Contract (On) Path = Off Path

ECC Interactions with Scheduling Dynamic Transfers Catalog Effort for Peak Telemetry Forecast Data Dynamic Schedules – energy profile accuracy? Pseudo-Ties – options e-Tag Build in ECC EIR Registration

ECCTF Task Force advising Peak on ECC Reorganized under Peak MAC Chair → Raj Hundal Meetings open to public

ECC Information https://www.peakrc.com/whatwedo/ECC/Pages/default.aspx