August 14 th NE Blackout and Common Roots of Blackouts Damir Novosel, PhD President KEMA Inc., T&D Consulting BLACKOUT AMERICANO E ITALIANO: LUNEDÌ, 10 MAGGIO 2004 ROMA

2 System Blackouts: Description and Prevention 1. US Grid 2. Descriptions of the August 14 th NE Blackouts 3. Common Roots of Blackouts 4. Conclusions

3 The US at night: the transmission grid Sparse load: Sparse network Dense load: Dense network 140 GW 650 GW 60 GW

4 Areas of retail competition

5 Regional reliability coordinators

6 Reliability coordinators & control areas: Complexity

7 Regional Councils and NE Blackout Effects ASCC Blackout Area n August 14, NE USA (8 states) and Canada (2 provinces) affected:  50 million people  34,000 miles of transmission  ~290 Generating units  ~61,800 MW  Restoration efforts  A day to restore power to NY City  Two days to restore power to Detroit Regional Councils

8 14 August temperatures

9 10:05:44Conesville Unit MW 1:14:04 Greenwood Unit MW 1:31:34 Eastlake Unit MW Aug. 14th NE Blackout: Initial Generator Outages

10 2,200 MW Power Reversal to Northern Ohio overloading the lines and causing voltage to decline 2:02Stuart-Atlanta 345kV trips due to a fault 3:05Harding-Chamberlain 345 kV sags into a tree 3:32Hanna-Juniper 345kV sags into a tree, other 345 kV lines disconnect => 16 of 135kV lines overload and trip 4:06 Sammis-Star 345kV trips on overload 4:09Galion-Ohio 345kV Central-Muskingum 4:09 East Lima-Fostoria 345kV August 14th Blackout – Some Key Events

20 Generators around Lake Erie (app. 2,174 MW) tripped Michigan lines trip 1256 MW Generator trips Transmission system separation Another power reversal, power flow (2,800 MW) to Northern Ohio through Ontario and Michigan The cascading events proceeded including apparent voltage decline. August 14th Blackout - Some Key Events Cascading Failure Complete at 4:13 PM

Four transmission lines between New York and Pennsylvania disconnect Further line and generation tripping in Ohio, New Jersey, and New York 4:10:46New York – New England Transmission Lines Disconnect 4:10:48New York Transmission Splits East to West August 14th Blackout - Some Key Events

:10:50Ontario system separates from New York 4:10:43Long Mountain – Plum Tree (345 kV Line) 4:10:45Remaining lines between Ontario and Eastern Michigan separate August 14th Blackout - Some Key Events

14 NE Blackout - Cascading Failure Complete at 4:13

15 August 14th Blackout - Power Plants Tripped

16 August 14 th Blackout Cascade Sequence

17 Common Roots of Blackouts n Caused by multiple contingencies with complex interactions  Usually no “single” cause  Sequence of low probability events difficult to accurately predict  Practically infinite number of operating contingencies, different from the expectations of system designers  Operators cannot act fast enough for fast developing disturbances

18 Pre-conditions and Factors for Blackouts n Congested grid  No lines & generators in my backyard!  Not enough reactive support n Tight operating margins, with less redundancy n Regulatory uncertainty n Low level of investment in recent years  How and who to invest?  How to recover costs? The bulk power system was not designed to transfer large amounts of power, but to improve network security

19 Pre-conditions and Factors for Blackouts n Inadequate right-of-way maintenance  FE failed to adequately trim trees n Aging equipment, prone to failures n Insufficiently coordinated equipment maintenance and generation scheduling n Weather (high temperatures; wind, thunderstorm, fog, etc.)

20 How Do Disturbances Turn Into a Blackout? Cascading events that cause disturbances to propagate n Sequential tripping due to overloads, power swings, and voltage fluctuations  Protection involved in ~70% of blackout events in North America  In some cases, protection miss-operation or unnecessary actions: incorrect settings, uncovered application design flows, or HW failures n Inadequate or faulty EMS/SCADA system (alarm burst)  E.g. FE lost its system condition alarm system around 2:14 pm  MISO (FE’s reliability coordinator) had an unrelated software problem and was unable to tell that FE’s lines were becoming overloaded n Insufficient reactive support where and when required n Inability of operators to prevent further propagation  Sacrifice own load or cut interties or get support from neighbors

21 Contributing Factors that Allow Blackout to Spread n Lack of coordinated response during developing disturbances  PJM saw the growing problem, but did not have joint procedures in place with MISO to deal with the problem quickly and effectively  Should we help or should we separate? n Inadequate planning/operation studies  FE didn’t ensure the security of its transmission system because it didn’t use an effective contingency analysis tool routinely n Lack of inadequate Special Protection Schemes to prevent spreading of the disturbance :  Prevent further overloading of the lines  Arrest voltage decline  Initiate pre-planned separation of the power system for severe emergencies

22 Conclusions n North-American Grid not designed for large transfers n Increase in the number and frequency of major blackouts n Analysis of recent disturbances reveals some common threads among them, leading to conclusions that:  Propagation can be arrested  Impact of disturbances/outages can be reduced n Various cures to reduce the possibility of future outages  A need for deployment of well-defined and coordinated overall plans (planning, operations and maintenance)

23 Evolution of the US grid Isolated Plant Individual System Regional Inter- Regional

24 How we got here n The “Golden Age”  Constantly lower prices  Constantly lower costs  Constant technology developments n The “Crush”  Fuel-price load-growth crisis  Environmental pressure  Extreme capital costs n The “Big Uneasy”  High prices force industry calls for restructuring  Restructuring uncertainty enervates utilities  Stranded cost obstacle to new generation  Fear of competition freezes new transmission n ???