Recent blackouts in US/Canada and continental Europe: Is liberalisation to blame?

1. Recent blackouts in US/Canada and continental Europe: Is liberalisation to blame? Janusz W. Bialek University of Edinburgh, Scotland

2. The Oregonian, 24 August 2003, after C. Taylor

3. Recent major blackouts • 6 blackouts within 6 weeks affecting 112 million people in 5 countries • 14 August 2003, USA/Canada: max ~62 GW lost, ~50M people, restoration up to a few days • 28 August 2003, south London, 724 MW lost, 410k people + Tube & Rail at rush hour, restoration: 40 min. • 5 September 2003, east Birmingham, 250 MW lost, 220k people, restoration: 11 min. • 23 September 2003, Sweden and Denmark, 5M people, restoration 4 hours • 28 September 2003, whole Italy except Sardinia, 57M people, restoration: 4 hours. • Who’s next?

4. What’s important for people and policy makers? • Electricity prices • Environmental effect • Security of supply

5. Recent blackouts • All blackouts were transmission-based • No problem with generation adequacy • Systems were not stressed prior to blackouts • Two categories: • Cross-border trades: continental Europe, USA • UK: different, single TSO • What went wrong?

6. US/Canada • 50M people affected, 11% of Eastern Interconnection • Widely covered • Here only short description after US/Canada Power System Outage Task Force “Interim Report: Causes of the August 14th Blackout in the United States and Canada” Nov. 2003.

7. NE of USA/Canada: before

8. NE of USA/Canada: after

11. How it all started: tree flashover Source: Gerry Cauley, NERC

12. Effect of a line trip: increased loading on other lines

13. Effect of a line trip: depressed voltage

16. Summary for US blackout • Root causes: • tree growth caused flashovers (FE), • inadequate situational awareness at FE due to computer failures • inadequate diagnostic support from MISO due to state estimator failure • Interim report identified root causes but failures do happen • Why a local failure was not contained? • What are the REAL underlying reasons? • Common features with European blackouts

17. Normal load • 1.1 GW nuclear plant trips in south. Sweden • 5 min later substation fault trips 1.8 GW nuclear plant and 2 lines in south. Sweden • Total: 2.9 GW + 2 lines lost: system not designed to handle • Local blackout perhaps unavoidable but why a cascade? Danish/Swedish blackout: 5 M people

18. Increased power transfers over fewer lines • Voltage dropping in Southern Denmark and Sweden • Additionally power and voltage swings • further lines tripped • Voltage collapse, power stations trip and separation • Blackout

19. Danish/Swedish blackout: summary • Again problems at the border but insufficient coordination less of the issue • Single mechanical fault in a separator triggered double busbar fault– very rare, need to investigate • Dependence of Eastern Denmark on supplies from Sweden • Most “technical” of the blackouts

20. Italy

21. 3 am: import 6.6 GW 24% of total demand, 300 MW over agreed level • Fully-loaded CH line touches tree and trips • Unsuccessful reclosing due to angle stability • 3.11 am: ETRANS informs GRTN (disputed) • GRTN reduces imports by 300 MW (not enough)

22. 3.25 another CH overloaded line sags and trips on tree flashover • Italy loses synchronism with UCTE • Dynamic interactions cause fast voltage collapse in Italy • Tie-lines trip almost instantaneously • Island operation: 6.4 GW generation deficit leads to frequency collapse • 10 GW of load shed automatically but 21 out of 50 thermal plants trip by under-voltage relays • Blackout 2.5 minute after separation: whole Italy, except of Sardinia.

23. Italy: summary • Largest blackout in Europe since WW2 • Over-dependence on imports: • 1987 referendum blocked nuclear power • Not enough power stations built • Relatively weak and congested tie-lines • Weak coordination between ETRANS and GRTN • ETRANS did not assess the urgency as the consequences of first outage were in Italy • GRTN could not assess the situation as the first outage was in CH • Angle instability and voltage collapse prevented successful island operation of Italy

24. Common features of US/Canada and European blackouts • Happened at the boundaries between control areas (countries) • Import areas dependent on transmission from export area • Were allowed to spread due to the insufficient coordinated response (to a lesser extent in Scandinavia) • What are the common underlying reasons? • Interconnection brings significant benefits but may be also a threat

25. North America • 3 interconnections (Eastern, Western, Texas) • 10 regional reliability councils and over 130 control areas! • balkanisation

26. Balkanisation

27. Europe's synchronous areas DC connection Source: P. Bonnard, 2003 IEEE Trans. Distr. Conf

28. Common patterns in US and Europe • Historically: self-sufficient utilities serving native load • Interconnections: • sharing generation reserves • help each other to deal with disturbances • Also limited coordinated exchanges • Maintaining conservative security margins • Liberalisation: • Uncoordinated cross-border trades (8% of generation in Europe, 4 times increase since 1998 in US) • Transmission systems run closer to the limits

29. Parallel flows: northern France – Italy trade Source: H-J Haubrich, W. Fritz

30. Unexpected flows in bottlenecks Source: P. Bonnard, 2003 IEEE Trans. Distr. Conf

31. Main generic reason for recent cascading blackouts • It is not liberalisation to blame but the way utilities operate • Operational procedures developed in the world of monopolistic, vertically integrated utilities cannot deal effectively with liberalisation, open access and cross-border trades • Phone-based communication • None sees the big picture • Limited exchange of real-time data • No automatic coordinated response to emergencies

32. The future • Is Mega-TSO a solution? • would probably create more problems than solve • politically unacceptable • New technical, organisational and political solutions needed for coordinated but decentralised operation • Alternative: more blackouts or restrain cross-border trades • Need to limit exchange of commercially sensitive information • Trade off between protecting local area and the whole interconnection

33. Fallacy: transmission investment will prevent blackouts • Bill Richardson, former US Energy Secretary: “we are superpower with third world grid”. • Underinvested grid suffers from bottlenecks but it may still be operated safely • Converse true • Increase in transmission capacity will be sooner or later used up • back to square one although at higher level Source: D. Kirschen, G. Strbac: “Why investments do not prevent blackouts” UMIST, 2003

34. Fallacy cntd. • Transmission investment enables competition and reduces prices but does not necessarily improve security in the long term • Operational rules are the key • They need to be adapted to the new situation

35. UK

36. UK blackouts • Birmingham and London: local blackouts • Remarkably similar to each other but different from US/European ones • NGC single grid operator in E&W, soon GB • In both cases recently commissioned protection equipment tripped due to wrong settings • Questions asked about commissioning procedures, use of outside contractors, maintenance scheduling, excessive downsizing • Findings not published

37. Conclusions • The blackouts were disasters waiting to happen • Underlying common reason: utilities need to adapt to liberalisation, open-access and cross-border trades • New framework of decentralised yet coordinated operation needed • It is not over yet!

38. Recent blackouts in US/Canada and continental Europe: Is liberalisation to blame? Janusz W. Bialek University of Edinburgh, Scotland