1. Experience you can trust. Hurricane Hardening Commission Staff Workshop on Electric Utility Infrastructure Richard E. Brown, PhD, PE rebrown@kema.com Tallahassee, Florida January 23 rd 2006

2. Page 2 © 2006 KEMA Inc. About the Presenter Richard E. Brown is a management and technical consultant for the electric power industry. He has published more than 70 technical papers related to power system reliability and infrastructure management; is a regular instructor on these topics; is author of the book Electric Power Distribution Reliability; and is a registered professional engineer. He is a senior member of the IEEE, chair of its working group on Distribution Planning and Implementation, and recipient of the Walter Fee Outstanding Young Engineer award. Richard earned his BSEE, MSEE, and PhD from the University of Washington in Seattle, and his MBA from the University of North Carolina at Chapel Hill. rebrown@kema.com

3. Page 3 © 2006 KEMA Inc. Agenda  Design criteria  Hurricanes  Hardening

4. Page 4 © 2006 KEMA Inc. Power Systems Generation Plant Generation Substation Transmission Substation Subtransmission Distribution Substation Distribution Transformer Service Drop Customer

5. Page 5 © 2006 KEMA Inc. Should a system be designed to withstand this? Page 5 © 2006 KEMA Inc.

6. Page 6 © 2006 KEMA Inc. Design Criteria  National Electrical Safety Code (NESC) – Grades of Construction – Extreme Wind Conditions  Reliability – Sometimes set by regulators – Sometimes set by utilities  Economic – Improve spending efficiency – Spend money to save money

7. Page 7 © 2006 KEMA Inc. NESC for Distribution Poles  Freeway crossings“Grade B”  Railroad crossings“Grade B”  Most other locations“Grade C”  Grade B is 50% stronger than Grade C

8. Page 8 © 2006 KEMA Inc. Distribution Pole Strength* *Grade C is the minimum requirement for most distribution poles. Extreme wind based on 145 mph gusts.

9. Page 9 © 2006 KEMA Inc. Hurricanes Page 9 © 2006 KEMA Inc.

10. Page 10 © 2006 KEMA Inc. Damage  Wind only  Trees  Debris  Flooding Page 10 © 2006 KEMA Inc.

11. Page 11 © 2006 KEMA Inc. Wind Only Hurricane Wilma was strong enough to snap concrete poles

12. Page 12 © 2006 KEMA Inc. Trees Tree damage is usually not preventable by the utility

13. Page 13 © 2006 KEMA Inc. Debris Flying debris is usually not preventable by the utility

14. Page 14 © 2006 KEMA Inc. Flooding Flooding can delay restoration efforts

15. Page 15 © 2006 KEMA Inc. Hardening Page 15 © 2006 KEMA Inc.

16. Page 16 © 2006 KEMA Inc. Wind on Pole Wind Forces on a Pole Wind on Conductors Wind on Attachments

17. Page 17 © 2006 KEMA Inc. Design for Extreme Winds  Based on 3-second gusts  Extreme wind rating (equivalent) – Grade B104mph – Grade C85mph  Florida extreme winds – Southern Coast145mph – North Central95mph

18. Page 18 © 2006 KEMA Inc. Extreme Wind Speeds (3 second gusts)

19. Page 19 © 2006 KEMA Inc. Hurricane Categories 1 minute average 3 second gust 104 85 145

20. Page 20 © 2006 KEMA Inc. “Storm Hardening” Toolkit  Stronger poles  More guying  Shorter spans  Anti-cascading  Conductor size  Fewer attachments  Undergrounding  Vegetation management

21. Page 21 © 2006 KEMA Inc. Cost of Hardening  New 3-Phase Construction – Typical Overhead:Typical cost – Hardened Overhead:2 to 4 times typical – Underground:5 to 10 times typical  Existing System – Much more expensive – Much more complicated – Could take 15 to 30 years

22. Page 22 © 2006 KEMA Inc. Hardening “Roadmap” Some Hardening Approaches  Entire system  New construction  Critical customer facilities  Customer-driven  Targeted hardening 10-20 Years Now

23. Page 23 © 2006 KEMA Inc. Richard E. Brown, PhD, PE rebrown@kema.com 919-593-2860