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Definition of Adequate Level of Reliability. Industry Webinar May 23, 2012, 1:00-3:00 p.m. ET. Outline. Background Definition and Reliability Objectives Supporting Documents Industry Feedback Next Steps Questions and Answers. Background. Background.
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Definition of Adequate Level of Reliability Industry Webinar May 23, 2012, 1:00-3:00 p.m. ET
Outline • Background • Definition and Reliability Objectives • Supporting Documents • Industry Feedback • Next Steps • Questions and Answers
Background • Adequate Level of Reliability Task Force (ALRTF) charged with: • Reviewing current definition of ALRTF (filed for information with FERC in 2008) • Determining if existing definition and characteristics need enhancement in coordination with the Member Representatives Committee’s (MRC’s) Bulk Electric System (BES)/ALR Policy Group • Task Force includes representatives from each of the Standing Committees : Standards Committee, Compliance and Certification Committee, Operating Committee, Planning Committee, Critical Infrastructure Protection Committee • Has met regularly since June 2011
Background • Goal: • Develop definition that encompasses NERC’s responsibility to ensure reliability • Define objectives and characteristics that are measurable* • Enable the ERO enterprise to focus on and align its activities with specific characteristics of ALR that have the greatest impact on BES reliability • Definition must be: • Concise, yet self-contained • Self-explanatory to BES planners and operators • Meaningful to policymakers; placing a premium on translation in the ALRTF Report *Qualitative only; quantitative measures to be developed via standards.
Background • Input from MRC’s BES/ALR Policy Group directed group to consider: • Cost/benefit • Load loss distinctions • Definition of Cascading
Draft Definition: Overview • Seven Reliability Objectives • Associated Expected Performance Outcomes • Expressed in four time frames: • Steady State • Transient • Operator response • Recovery and system restoration • Associated Disturbances • Both predefined and beyond the scope of predefined Disturbances
Draft Definition: Preambles • Reliability objectives are “what’s” not “how’s” • Not bound by jurisdictional implications • Reliability objectives support standards development • But not every reliability objective requires or will result in a standard • Each objective has some expected performance outcomes under specific events • i.e., when subject to predefined Disturbances • Expected performance outcomes are presented qualitatively at a high level, in different time frames • Predefined Disturbances are “categorized,” not details
Draft Definition: Time Frames • Time frames for expected performance outcomes: • Steady State – pre-disturbance • Transient – during the disturbance, from milliseconds to seconds, with automatic responses and control actions • Operator response – from seconds to minutes/hours, with some automatic actions plus operator actions • Recovery and system restoration – post disturbance, from minutes to hours, with actions to re-establish a sustainable operating state and then a new steady state that meets specific reliability objectives established by the circumstances of the Disturbance
Predefined Disturbances • Predefined Disturbances – the events under which the performance outcomes are expected • Predefined Disturbances set the scope of expected performance outcome for Reliability Objectives 1 to 5 • Not applicable to Objectives 6 and 7 as these two address post-Disturbance situations • Predefined Disturbances are deterministic, but are deemed to have a reasonable probability of occurring • To scope the design, planning and operation of BES • e.g., loss of single transmission circuit due to lightning strike
Predefined Disturbances • Predefined Disturbances – specific events or grid Disturbances in 3 categories: • Steady state, no contingencies: everything more or less as expected/forecast • Events resulting in loss of BES element(s) in a single protection zone • e.g., due to equipment failure, lightning strike on a transmission tower tripping a single circuit • Events resulting in loss of two or more BES elements not in a common protection zone • e.g., due to protection or breaker failure to clear initial faults; lightning strike on a transmission tower tripping two circuits
Predefined Disturbances • Beyond Predefined Disturbances – specific events or Disturbances in two categories: • Extreme Events: Two or more dependent or separate events occurring simultaneously, or in close time proximity, resulting in the removal of two or more BES elements not common to a single zone of protection • e.g., tornadoes removing circuits on the same right of way; common cause resulting in the loss of a substation or a generating plant • High-Impact, Low-Frequency (HILF) Events: A class of improbable events with the potential to significantly affect the reliability of the BES • e.g., Geomagnetic Disturbances (GMD); coordinated cyber and/or physical attacks
Reliability Objective #1 • The BES is free from instability, uncontrolled separation, Cascading, and voltage collapse under normal operating conditions and when subject to predefine Disturbances. • Expected performance outcomes: • Stable frequency and voltage within predefined range • Adequate reactive reserve maintained • No Cascading • Applicable Time Frames (1, 2, 3): • (1) Steady State • (2) Transient • (3) Operator Response
Reliability Objective #2 • BES frequency is maintained within defined parameters under normal operating conditions and when subject to predefined Disturbances. • Expected performance outcomes: • Stable frequency within predefined range • BES equipment frequency limits satisfied • Frequency oscillations experience positive damping • Applicable Time Frames (1, 2, 3): • (1) Steady State • (2) Transient • (3) Operator Response
Reliability Objective #3 • BES voltage is maintained within defined parameters during normal operating conditions and when subject to predefined Disturbances. • Expected performance outcomes: • Stable voltage within predefined range • BES equipment voltage limits satisfied • Voltage oscillations experience positive damping • Applicable Time Frames (1, 2, 3): • (1) Steady State • (2) Transient • (3) Operator Response
Reliability Objective #4 • Sufficient transfer capability of the BES transmission system is provided and maintained to meet required BES demands during normal operating conditions and when subject to predefined Disturbances. • Expected performance outcome: • Deliver sufficient resources to meet load obligations using the BES while operating within established operating parameters (e.g. thermal, voltage, equipment ratings) • Applicable Time Frames (1, 2, 3): • (1) Steady State • (2) Transient • (3) Operator Response
Reliability Objective #5 • Sufficient resource capability on the BES is provided and maintained to meet required BES demands during normal operating conditions and when subject to predefined Disturbances. • Expected performance outcome: • Have sufficient resources to meet load obligations within established operating parameters (e.g., ancillary services). • Applicable Time Frames (1, 2, 3): • (1) Steady State • (2) Transient • (3) Operator Response
Reliability Objective #6 • Adverse Reliability Impacts on the BES resulting from conditions beyond the scope of predefined Disturbances (e.g., multiple contingences, unplanned and uncontrolled outages, cyber security events, malicious acts) are minimized. • Expected performance outcomes: • Propagation of cascading or collapse limited • The BES is returned to a stable state with resources and load restored efficiently • Applicable Time Frames (2, 3, 4): • (2) Transient • (3) Operator Response • (4) Recovery and System Restoration
Reliability Objective #7 • The system has the ability to recover from major system Disturbances, such as blackouts and widespread outages, by restoring BES Facilities in a controlled manner that rebuilds BES integrity and restores supply to load. • Expected performance outcome: • Recover the BES and restore available resources and load to a stable interconnected operating state expeditiously after a major system Disturbance • Applicable Time Frames (4): • (4) Recovery and System Restoration
Examples of Expected Performance Outcome • BES is stable and exhibits positive damping after a predefined Disturbance • Steady state frequency at 60 Hz +/- a margin • Disturbance Control Standard (DCS): • Recovery in 15 minutes • Steady state voltage at nominal value +/- a margin • Sufficient transmission transfer capability to deliver resource to meet system demand under peak load condition • Loss of load probability at x day/y years
Technical Document Technical Report Supporting Definition of Adequate Level of Reliability” • Introduction • Overview of ALR Definition Structure • Performance Outcomes • Causes of Disturbances • Comparison with current ALR definition with the proposed ALR definition • Appendix: Means to Meet Reliability Objectives (with examples for illustration)
Other Associated Work • Discussion Draft: Mapping of Adequate Level of Reliability for the Bulk Electric System to Standards Development Reliability Principles • Discussion Paper: Risk Tolerance for Widespread Bulk Electric System Outages with Significant Socio-Economic Impacts of Reliable BES Operations
Discussion Paper:Risk Tolerance for Widespread BES Outages with Significant Socioeconomic Impact
Optimizing Risk Mitigation to the Risk • What is the “right” balance of costs of risk prevention vs. the cost of the risk itself? • Society cannot afford the cost of a power system immune to blackouts • Society cannot afford too many blackouts • We know how to measure costs, but, how do we measure risk? • Probabilistic Risk Management framework • We do not currently have the data necessary to perform this risk analysis, but, we are already working towards it…
Defining a Risk Tolerance • What are the magnitudes of risk and probability of risk that society can and cannot tolerate? • Magnitude • Society has a fairly high tolerance for localized distribution outages • Society has a low tolerance for widespread blackouts • What magnitude of risk/blackout is worth managing from a continental, socioeconomic perspective? (e.g., how much water makes a flood?) • Frequency • It cannot be never • It cannot be once a year • Is there a metric similar to the 30 year flood plain that we can develop? • Risk Tolerance = fulcrum point balancing of social cost of mitigation vs. social cost of the outage risks
Managing Risk 3. High Impact, Low Probability 1. High Impact, High Probability High Severity 2. Low Impact, High Probability 4. Low Impact, Low Probability Low High Low Probability
Managing Risk • Quadrant 1: High Impact, High Probability • Plan, design and operate to prevent risks from residing in this quadrant • Quadrant 2: Low Impact, High Probability • Establish deterministic criteria, e.g., operate within limits for a single contingency • Quadrant 3: High Impact, Low Probability • Two strategies: • Emergency preparedness and response to reduce both impact and probability of an event (acts of nature, extreme “bad luck”) • Defense in depth (acts of aggression) • Quadrant 4: Low Impact, Low Probability • Learning opportunities
Should We Head in This Direction? • Migrate from ALR criteria largely deterministic in nature to criteria more probabilistic in nature? • Develop stochastic analytical methods to define ALR based on many variables and a balance of cost of risk mitigation vs. the cost of the risk itself? • Similar to Loss of Load Probability (LOLP)/Loss of Load Expectation (LOLE) analyses that are used to determine resource adequacy at the State/Province level • If so, what are the recommended next steps?
Question 1 • ALRTF chose to develop the ALR definition by presenting the performance state that the design, planning, and operation of the BES will achieve by meeting a set of reliability objectives • Do you agree with this approach?
Question 2 • Reliability Objectives #1, #2, and #3 are aimed at maintaining BES integrity and normal operating state (voltage and frequency ranges) • Do you agree with these reliability objectives and their associated performance outcomes?
Question 3a • Reliability Objectives #4 and #5 are aimed at maintaining adequate BES capabilities (resource and transmission) to meet required BES demands. • Do you agree with these reliability objectives and their associated performance outcomes?
Question 3b The ALRTF concluded that: • Meeting required BES demands is the fundamental reason for ensuring BES integrity and maintaining normal operating states (voltage and frequency). • Adequate resource and transmission capabilities need to be provided to meet forecast demands. • EPA 215 does not provide FERC and NERC the authority to require or enforce provision of these capabilities, • The ALRTF proposes these reliability objectives only to aid assessment of future needs but does not prescribe how or by whom the required BES capabilities will be provided. • Do you agree that this is an acceptable approach?
Question 3c • In Reliability Objectives #4 and #5, the ALRTF uses the phrases “required BES demands” and “meet load obligations” to refer to transmission and resource adequacy. • Do you believe this language is clear?
Question 4 • Reliability Objectives #6 and #7 are aimed at responding to BES events that go beyond those covered in Reliability Objectives #1-5 (beyond the predefined Disturbances) • Do you support these objectives?
Question 5 • Performance Outcomes and Disturbances • Technical Report provides additional detail, but at a high level • Specific performance outcomes and Disturbances will be developed in the standards development process • Do you support this approach?
Question 6 • Time Frames • The Technical Document presents four time frames for performance outcomes. • Does this help fully describe each performance outcome?
Question 7 • Does the ALRTF’s proposed definition of ALR improve upon the current definition? • Current definition was filed with FERC for information in 2008 Current definition of ALR: http://www.nerc.com/files/Adequate_Level_of_Reliability.pdf
Question 8 • NERC’s 8 Reliability Principles and ALR: • Reliability Principles are approved by NERC’s Board and are incorporated into the Standards Processes Manual • As of now, new standard requirements must be tied to one of the principles • Are both the Reliability Principles and ALR Definition necessary? Reliability Principles: http://www.nerc.com/files/Reliability_Principles.pdf
Question 9 • BES v. Bulk-Power System (BPS) v. System • BES: NERC Glossary Term • BPS: Specific statutory definition applicable within the U.S. • System: Used in the current Board-approved definition of ALR, but is very broad • ALRTF chose to use BES; do you support this approach?
Question 10 • Other comments or feedback?
Schedule • April 23 - June 23, 2012: Public comment period • May 23, 2012: Webinar • June 28, 2012: ALRTF Meeting • July - August, 2012: Revise Draft ALR Definition and Technical Document based on comments; prepare and submit package for Board of Trustees endorsement/consideration; consider next steps on Socio-Economic Impact Discussion Paper.
Questions? Allen Mosher ALRTF Chair (202) 467-2944 amosher@publicpower.org Mallory Huggins ALRTF NERC Coordinator (202) 644-8062 mallory.huggins@nerc.net