# Presentation: 877158

## Emergency Operations March 9-10, 2005

- The Structure Group
- 2000 W. Sam Houston Pkwy. South
- Suite 1600
- Houston, TX 77042

- Copyright 2004 by The Structure Group.  All rights reserved.  Proprietary and Confidential

## Emergency Operations Emergency

- Emergency:
- An abnormal system condition that requires manual or automatic action to prevent or limit loss of transmission facilities or generation resources that could adversely affect the reliability of the electric system.
- A condition where an LSE is, or expects to be, unable to provide its customer’s energy requirements, and has been unsuccessful in locating other systems from which to purchase, or cannot schedule resources due to system limitations, e.g., AFC or transmission loading relief.

***As the Reliability and Balancing Authority for the CCA footprint, Grid West will be responsible to direct and implement emergency procedures.***

- Copyright 2004 by The Structure Group.  All rights reserved.  Proprietary and Confidential

## Emergency Operations Current State vs. Future State

- Current state:
- Each control area has reliability authority and balancing responsibilities over its territory - including directing and implementing emergency procedures.
- PNSC, NWPP and control areas work together to identify and declare emergency conditions as necessary.
- Future state:
- Each control area (including CCA over combined territory of consolidating TOs) will continue to have reliability authority over its territory.
- Grid West is also TSP and TxOp over entire Grid West footprint
- Still open how will this with work without RA over the same footprint
- PNSC, NWPP and control areas will continue to work together to identify and declare emergency conditions.

***Reliability Authority responsibilities - Current vs. Future***

- Copyright 2004 by The Structure Group.  All rights reserved.  Proprietary and Confidential

## Emergency Operations SOL and IROL

**System Operating Limit (SOL)**. The value (such as MW, MVar, Amperes, Frequency or Volts) that satisfies the most limiting of the prescribed operating criteria for a specified system configuration to ensure operation within acceptable reliability criteria. System Operating Limits are based upon certain operating criteria. These include, but are not limited to:
- Facility Ratings (Applicable pre- and post-Contingency equipment or facility ratings)
- Transient Stability Ratings (Applicable pre- and post-Contingency Stability Limits
- Voltage Stability Ratings (Applicable pre- and post-Contingency Voltage Stability)
- System Voltage Limits (Applicable pre- and post-Contingency Voltage Limits)
**Interconnection Reliability Operating Limit (IROL). **The value (such as MW, MVar, Amperes, Frequency or Volts) derived from, or a subset of the System Operating Limits, which if exceeded, could expose a widespread area of the Bulk Electric System to instability, uncontrolled separation(s) or cascading outages.

***NERC defined quantities used to determine emergency conditions***

- Copyright 2004 by The Structure Group.  All rights reserved.  Proprietary and Confidential

## Emergency Operations Monitored System Conditions

- Key System Conditions
- Thermal facilities actual and post-contingency flows: transmission paths, transmission lines, transformers, PARs.
- Voltage – actual and post-contingency
- Generation facilities – status, active and reactive outputs, response capability
- Active and reactive reserves – requirements, actual amount and location
- ACE, system frequency, total system load and generation, actual interchange, scheduled interchange, short-term load forecast
- Neighboring systems: major facilities, ACE, reserves
- Status/outage of generator and transmission facilities
- Status of RAS and system conditions requiring RAS operations
- System disturbances
- Computer and communication Systems
- Environmental conditions, natural disasters, man-made conditions

***Grid West will monitor system conditions and declare emergencies as appropriate ...***

- Copyright 2004 by The Structure Group.  All rights reserved.  Proprietary and Confidential

## Emergency Operations Actions

- Warning has been issued
- Discretionary exports halted
- Scheduled maintenance of transmission and generation facilities may be shifted
- Explore option for increasing exports
- Resources may be operated beyond “soft limits” to nameplate capacity
- Assistance from external areas may be arranged
- Options to reduce load from applicable contracts may be exercised
- Violation is imminent
- Re-dispatch generation
- Re-configure transmission
- Manage interchange transactions
- Reduce system load until interchange transactions can be reduced
- If violation occurs or condition progresses
- Implement a local (Regional, Interregional, or subregional) transmission loading relief procedure or an Interconnection-wide procedure

***Grid West will undertake actions to mitigate violations ...***

- Copyright 2004 by The Structure Group.  All rights reserved.  Proprietary and Confidential