Nashville Electric Service Dealing With a Disaster and Its Effect on the Utility Operation UTA Fall Conference Florence, Alabama October 12-14, 2011
Outline Who We Are Typical Emergency Response Challenges of a Flood How We Responded Outrageous Successes /Areas for Improvement Conclusions Q & A
Who We Are Our official name is the Electric Power Board of Metropolitan Government of Nashville and Davidson County. NES is one of the 12 largest public electric utilities in the U.S. We serve more than 357,000 customers. We have 986 employees.
Mission To provide safe, reliable, and economical electric power for our customers
Service Area Our service area is more than 700 square miles. We serve all of Nashville and Davidson County and portions of the six surrounding counties.
Financial Total revenue in fiscal year 2010 - $1.06 billion NES has a AA+ bond rating with Fitch and Standard & Poors. In April 2010, NES received APPA's "Reliable Public Power Provider" (RP 3 ) Diamond designation, one of only six public power utilities to receive the award.
The NES System NES has no generating capacity and purchases all energy requirements from TVA. NES interconnects with the TVA power system at 24 locations across our 700-square-mile service area. NES purchases power at 161,000 volts (161 kv) and receives power from two hydroelectric facilities at 69,000 volts (69 kv). NES operates an extensive 69 kv sub-transmission system interconnecting some 50 substations. NES utilizes distribution circuit voltages of 4,160 volts (4 kv), 13,800 volts (13.8 kv) and 23,900 volts (23.9 kv). NES summer peak system demand - 2,700 MW.
Major Facilities Headquarters in downtown Nashville Executives, engineering, human resources, accounting, call center, data center/staff, customer lobby, control center, underground/substation construction and maintenance, metering, garage, fuel station. Donelson Service Center on east side of Nashville One-half of overhead line crews, bucket trucks, augers, poles, crossarms, OH transformers, OH cable, OH materials. Garage, fuel station, substation. West Service Center on west side of Nashville One-half of overhead line crews, bucket trucks, augers, poles, crossarms, OH transformers, OH cable, OH materials. Garage, fuel station, substation.
Power Outages Caused By: Equipment Failure Outside Influences Animals Drunk Drivers Weather Ice Wind Lightning Trees Falling on Lines Typical Emergencies
Typical Responses Identify Outages SCADA Customer Calls to IVR Field Damage Assessment Sectionalize Mobilize Resources Repair
Emergency Response Plan Crisis Classification System Crisis Management Team Contact Lists Restoration Priorities Contracts in Place Line Crews Contractors and Other Utilities Vegetation Management Crews Arrangements in Place Hotels Restaurants Parking Fuel Communications
The Problem
The resulting floods and subsequent rising of the Cumberland River would: Cause extensive damage to NES West Service Center and three major substations. Force NES system control to disconnect portions of the downtown underground network from service. Cause widespread damage to the general overhead and underground distribution system across Nashville. During the time period from 7:30 a.m. Saturday, May 1, until 7:00 a.m., Monday, May 10, almost 90,000 of NES 355,000 customers experienced an outage. The maximum number of customers without power at any one point in time occurred at 1:58 p.m., Sunday, May 2, when 43,677 customers were without power.
Riverfront Downtown Nashville
Schermerhorn Symphony Center
Country Music Hall of Fame
LP Field
West Service Center
Challenges of a Flood Identify Outages SCADA Customer Calls to IVR Field Damage Assessment impeded by road closures Sectionalize impeded by road closures and flooded vaults downtown
Challenges of a Flood Mobilize Resources Headquarters fully intact control center, call center, data center/staff, telecommunications Most employees were able to report for work Lost West Service Center Had to rescue workers who were trapped by flood waters Lost 37 vehicles buckets, augers, similar large vehicles Employees lost about 40 personal vehicles Lost half of NES overhead materials poles, crossarms, OH transformers, OH cables, other OH materials Lost many tools and rubber goods Had to address environmental issues from fuel spillage Had to address problem of materials floating onto adjacent roadway
Challenges of a Flood Repair Tremendous amount of work for underground and substation crews Water leaked into underground conduits potential long-term failure Water rose through conduits into customer switch gear
How We Responded Identify Outages SCADA Customer Calls to IVR Field Damage Assessment Sectionalize Water receded rapidly except downtown Recruited high capacity pumps from downtown convention center contractor to pump out downtown vaults
How We Responded Mobilize Resources Called in contractor buckets Leased bucket trucks for NES crews Moderate overhead damage reduced strain for overhead materials Moved West Service Center crews to downtown headquarters Initially parked in the street Later rented a nearby building
How We Responded Repair Lots of overtime especially for underground and substation crews
Outrageous Successes Proactive phone calls to 75 key accounts Press releases to media and on web site Social networking Mayor s daily news conference Streamlined energy efficiency credit process Temporary overhead service to Opryland
Temporary Service for Gaylord Opryland May 3 early A.M. Service disconnected at customer request May 4 A.M. First meeting with Gaylord May 4 P.M. On site engineering May 5 11:30 P.M. Completed temporary overhead service Sixteen poles; nine anchors One 3-phase meter Four 3-phase transformer banks with secondaries 3,015 feet of 3-phase conductor; 220 feet of secondary
Areas for Improvement Protection of our resources Assistance for our employees (they had no way to get home on Sunday evening May 2 because their personal vehicles were under water) Problems re-energizing meter bases that had been under water No way to waive minimum bills
Conclusions Preparation for a crisis is good Communication and responsiveness during a crisis is even better
vhatridge@nespower.com Questions/Answers