AEP Sustainability - Aging Infrastructure

Managing an Aging Infrastructure

At AEP, we constantly evaluate the performance and condition of the grid. We prioritize investments by identifying the aging facilities that have historically caused customer outages and using analytics to help us predict where failures will occur in the future. Making the investments necessary to upgrade and replace our aging transmission and distribution grid is essential to maintaining the highest levels of reliability and resiliency.

Making investments to upgrade and replace our aging transmission and distribution grid is essential to maintaining the highest levels of reliability and resiliency.

The Edison Electric Institute (EEI) estimates that at least 30 percent of the U.S. transmission system is at or near the end of its useful life. AEP is a part of this aging system; we own and operate the largest transmission network in America, with approximately 40,000 miles of transmission lines spanning across 11 states. The average age of these lines is 47 years. In addition, the average age of our transformers is 34 years. As a result, replacement parts for certain pieces of equipment are no longer available. This poses a substantial challenge to keeping our system in working order. While AEP has always invested in our transmission system, at this time, there is significant focus on renewing aging transmission infrastructure which is why we are currently investing billions of dollars to modernize the power grid, make it more resilient and increase customer value.

AEP’s distribution system is no exception. The average age of our distribution poles is 32 years, with an expected life of 45 years. Throughout AEP’s service territory, there are more than 86,000 miles of small conductors that are at least 40 years old.

As we rely on a system that is at or near the end of its useful life, we become more susceptible to experiencing more frequent and prolonged power outages from equipment failure. In addition, older transmission and distribution equipment is not compatible with newer grid technology, such as digital meters and sensors, which poses an increasing challenge to grid modernization efforts.

Some recent examples of our progress in replacing our aging infrastructure include:

  • In Shreveport, Louisiana, Southwestern Electric Power Company (SWEPCO) is investing $9 million to replace a three-mile stretch of 69 kV transmission line and 60-year-old wooden poles and upgrade two substations. The installations will improve reliability of the local grid, and the project is scheduled to go into service in 2019.
  • AEP Ohio is rebuilding approximately 55 miles of a 138-kV system built in 1954 in Athens and Hocking counties, Ohio. The $62 million project is expected to go online in mid-2019.
  • In southern West Virginia, Appalachian Power is investing approximately $100 million to make significant upgrades to the existing transmission system. The two-phase project will strengthen the grid in Boone and Kanawha counties by replacing aging equipment with modern technology. The project is expected to be completed by the end of 2020.
  • With more than 210,000 wooden power poles to maintain, a Kentucky Power initiative targeted poles that are 50 years or older to be treated, reinforced or replaced. Treated and reinforced poles are less likely to topple during storms and can last as many as 20 additional years, reducing replacement costs.

We rely on having instantly available accurate data to manage and operate the electric power grid. The two systems integral to operating and managing the grid are the Energy Management System (EMS) and the Supervisory Control and Data Acquisition (SCADA) system. These are critically important because of the wide range of age, health and complexities of the network that makes up the North American Transmission Systems (Eastern Interconnect, Western Interconnect and Texas Interconnect). To help us gain greater visibility of all elements of the grid we have been increasing the scale of these systems to gain more real-time monitoring and assessments. During the last three years, AEP has added up to 130,000 points per year to the SCADA system and up to 5,000 nodes to the EMS system. These enhancements help us detect equipment failures as well as gain advance notice of potential trouble spots before they can affect customers. The investments we are making to enhance these systems also strengthen the resilience of the grid.