WECC Annual Meeting 9/11/2018 Cameron Warren

Entergy’s Transmission System Entergy Overview HQ in New Orleans, LA Approximately $11 B revenues More than 13,000 employees ~15,700 circuit miles of transmission lines (operated at 69kV to 500kV) and ~1,500 substations Approximately 30,000 MW of generating capacity, including 9,000 MW of nuclear power Reliably serves 2.9 million utility customers in AR, LA, MS, MO, TX Regulated by FERC, APSC, LPSC, MPSC, PUCT, and City Council of New Orleans 161 kV lines 115 kV lines 500 kV lines 230 kV lines 138 kV lines 69kV lines Entergy’s Transmission System

Entergy Reliability Coordination History 1998 – Entergy leaves Southwest Power Pool (SPP), picking up the role of Reliability Coordinator 2006 – Entergy receive FERC approval for Independent Coordinator of Transmission (ICT) SPP, in an independent oversight role, administers the Entergy Tariff and serves as the Reliability Coordinator for Entergy 2012 – MISO becomes the ICT for Entergy November 2012, MISO begins administering the Tariff and serving as Entergy’s RC 2013 – Entergy joins the MISO RTO December 2013

Congestion Management along Seams Entergy has ties with multiple utilities with many having different RCs RCs: MISO, SPP, SOCO, TVA, ERCOT(emergency tie) Some are in MISO or SPP market, and some are not Methods of controlling congestion along seams Established joint operating agreements Standing Operating guides NERC TLR process As a TOP if Entergy observes congestion at the seams or congestion being impacted by another utility, Entergy works with MISO as the RC to address Neighboring TOPs communicate directly for outage coordination and the operating of tielines. RCs are kept informed and get involved if necessary to resolve conflicts.

Real-Time Modeling Past studies indicated how much of the neighboring system needed full topology and how much could be equivalenced . Entergy taking an approach to go to full topology for all first tier neighbors. Model expanding from ~ 4,000 buses to ~16,000 buses. Better representation under varying conditions (loop flows) Easier external model updates Prepares a pathway for utilizing CIM model exchange within SERC Better alignment with our RC Coordination among neighboring entities SERC RMWG Utilize information from MISO model

Contact info Cameron Warren Mgr., Transmission Operations Engineering cwarre1@entergy.com Tel: (501)228-2899