AEP Corpus Christi TDC Advance Outage Scheduling Initiative

Goal  Focus on preferred windows for most critical circuits  To have transmission outages submitted in a greater lead time frame with respect to the intended outage date  To comply with ERCOT Nodal Operating Guides (Section 9) which dictates monitoring programs for TSP’s Outage Scheduling and Reporting

Transmission Clearance Windows List  Transmission Clearance Window List - detailing outage scheduling windows and seasons – developed among TS and TO. Enforcing the timeframe windows

Window Preference  Long restoration planned outages for critical circuits are blocked from winter and summer periods  Defined preference for long restoration outage times to fall and early spring  Quick restoration and critical circuit outages are best done in winter for our south area

Pre Arranged Outage Request Timelines  Type 1) 48 CALENDAR DAYS - PREARRANGED OUTAGE REQUEST form required Requests that can lead to cascading outages and load shedding should be requested 48 calendar days in advance. ERCOT requires 45 day notice for load shedding situations. Examples of these are the Airline autos, Victoria autos and the 345kv lines into the Valley and the cross Valley 345kv line.  Type 2) 12 BUSINESS DAYS - PREARRANGED OUTAGE REQUEST form required Requests that are on the defined critical component list developed with Transmission Services should be requested with 12 business days in advance. These critical components are ones in which there is likely to be difficult scheduling problems with generation or must be done in a small time window of the year to be typically accepted by ERCOT. This also locks in an approval response time from ERCOT of 4 days and the ability to have replacement requests within the minimum ERCOT request time of 3 days. Examples of these are the remaining 345kv lines, buss clearances and components that typically create local constraints.  Type 3) 6 BUSINESS DAYS - PREARRANGED OUTAGE REQUEST form required Requests for non load shedding and non critically defined components should be requested with 6 business days in advance. Examples of these would be all remaining components that will affect the network through flows.  Type 4) 3 FULL CALENDAR DAYS – or fax required, Use of form encouraged. Fall back or filler requests that do not change the network through flows but must be approved by ERCOT will be allowed with the ERCOT minimum of 3 full calendar days. An to "TDispatch" with "No network MW flow through change clearance request" in the subject line and with a follow up verbal call to the Transmission Dispatcher is required. Examples of these are a single breaker on a double breakered line and a total clearance outage time of 1 hour or more.  Type 5) DAY BEFORE THE WORK – or fax required. Use of form encouraged. Fall back or filler requests that do not change the network through flows and can be done well within 1 hour total outage time will be allowed when other jobs have been cancelled. An to "TDispatch" with "Well less than 1 hour and no network MW flow through change clearance request" in subject line and with a follow up verbal call to the Transmission Dispatcher is required. These Requests should be received the day prior to the work unless the situation precludes doing this. Examples of these are relay testing requiring less than a total outage time of 1 hour and that do not take a line out.

Generation Versus Transmission  Valley 345kv cross arm replacement was rejected or rescheduled 3 times this past year because of generation scheduling  500 MW plant displacing an 1100 MW line capability – Does this make sense?  ERCOT needs tools to allow these more critical lines to have preference

What Are Some of the Pitfalls  Unexpected weather and restoration efforts interrupting a previously planned and scheduled outage  Unexpected construction delays due to material, permitting, contractor issues, etc..  Forced outages within the system that pulls crews away from intended work

What AEP Groups Can Do  HELP and ASSIST to accomplish our goals as best we can by communicating your plans Project Managers – Communicate information and schedules regarding your projects as early as possible with the TDC Coordinators – Even if its too early to pin down clearance dates, we can determine date ranges for clearances and look at optimal outage windows. Also, the energizing new stations/devices need to be coordinated with model changes and those strict deadlines. Keep TDC in the loop for all project meetings please – we will try our best to have someone present Substation – Set dates for required outages for work plan maintenance and capital improvement work as soon as plan is obtained from the asset management group or work order has been approved. Dates should be set as early as possible and worked towards. TCR’s – Submit clearance requests as soon as PM schedule indicates target clearance date and be in constant communication with TDC Coordinators for changes needed.

Questions ?