AEP Sustainability - Grid Resilience

Grid Resilience

Resilience is our ability to maintain optimal grid performance and recover quickly from system disruptions. Many external factors influence how AEP addresses the resilience of the grid, including severe weather, cyberattacks, terrorism, theft, electromagnetic impulses, vandalism and supply chain disruptions.

Weather remains one of the greatest threats to the electric power grid, and the impacts caused by significant storms can be long-lasting and widespread.

Making the grid more resilient goes hand-in-hand with grid modernization. Today, we are using technology to help us find, fix and restore service faster. For example, we are putting sensors on power lines and circuits that can quickly tell us where a system fault has occurred so we can dispatch crews to make repairs. Without the sensors, our crews would first have to find the problem before they could make repairs. These initiatives have the support of state utility commissions because these types of activities improve system reliability and satisfaction for all customers.

Grid “hardening” refers to the ability of the grid to withstand and recover from abnormalities and external forces. Actions that we take to harden the grid include replacing infrastructure when needed or before assets fail in severe weather. Grid hardening incorporates higher-strength line designs, effective tree trimming and vegetation management and strategic system reinforcements (e.g., storm guys) to assure a reliable delivery of energy to customers.

Building out our fiber communication systems and cybersecurity protections allows us to manage the system remotely. We are implementing several telecommunications projects that will modernize the grid and improve the speed and efficiency by which AEP can relay and respond to information in the field. We have also invested significantly to modernize our underground networks on our distribution system to give us real-time visibility to how the system is working.

Severe Weather

Weather remains one of the greatest threats to the electric power grid, and the impacts caused by significant storms can be long-lasting and widespread. In 2017, AEP Texas experienced its strongest storm in 44 years when Hurricane Harvey hit the southeastern Texas coast, knocking out power to approximately 220,000 customers. While power was restored to all remaining customers following the storm, the work of repairing transmission lines and poles, substations and service centers continues today.

As part of these restoration efforts, AEP Texas is executing a long-term plan to enhance the resiliency of the system against future severe weather events. This includes using stronger transmission poles and shorter line spans between towers.

In 2018, we completed an expedited rebuild project near Aransas Pass, Texas, to replace a 69 kV transmission line knocked out during Hurricane Harvey. The new line spans an eight-mile section between substations in Aransas Pass and Mustang Island and will serve to strengthen the local power grid.

During the course of one week in April 2018, five tornados touched down in the state of Ohio, including an EF-1 tornado that caused significant damage in Grove City. The storm knocked down 32 wooden poles and cut power to 8,500 people. In the immediate aftermath of the tornado and before our crews began restoring power, they safely rescued nearly a dozen people trapped in their cars under downed power lines. We were able to restore power to nearly all customers within a few hours thanks to creative solutions to route power around the damaged areas and minimize the disruption to our customers. As a result of that storm, we replaced 24 wooden transmission structures with new steel poles.

The electric utility industry has a longstanding mutual aid agreement that provides support – people and equipment – to utilities in the wake of a natural disaster. AEP has helped other utilities in states across the U.S., and we have also received help when we needed it. The original agreement did not provide for mutual aid to utilities off the mainland, so when Hurricane Maria struck Puerto Rico in 2017, the industry worked with Edison Electric Institute (EEI) and the island’s utility to extend the agreement to Puerto Rico.

Recovery efforts in Puerto Rico continued well into 2018, during which time AEP deployed 157 employees, including incident command teams and frontline workers, in support of the mission. In total, nearly 60 electric companies and public power utilities sent more than 3,000 employees, plus equipment and/or materials to Puerto Rico. Eleven months after Hurricane Maria struck the island, the Puerto Rico Electric Power Authority (PREPA) announced that power had been restored to its customers, ending the longest blackout in U.S. history.

Each year, EEI recognizes member companies who show outstanding efforts to restore service to areas following severe weather or other natural disasters. In 2018, EEI presented AEP with the 2018 Emergency Assistance Award for Puerto Rico Power Restoration. This award was also given to each AEP operating company and AEP Transmission for their support in the emergency power restoration mission after Hurricane Maria.

Grid Assurance

While the nation has improved its ability to respond to major grid disasters and power outages that frequently result from catastrophes, there are increasing threats – including more frequent and extreme weather events and physical, cyber or electromagnetic attacks – which present new challenges for protecting and recovering quickly from a catastrophic power outage. Maintaining an adequate inventory of vital equipment needed to replace critical infrastructure in the case of such an event is one challenge to improving grid resiliency.

Transmission components are expensive and often difficult to transport over long distances, and the manufacturing process itself is complex, with many components being hand-assembled at the factory. This dramatically increases lead time in ordering new equipment, and it is not uncommon to wait 18 months for delivery of some components. As a result, it is expensive for individual companies to purchase and keep a large quantity of spare transmission equipment on standby. For this reason, in 2018, AEP joined seven other major utility companies in becoming founding subscribers of Grid Assurance, LLC.

Grid Assurance was designed to help restore power more quickly following a high-impact, low-frequency event by providing subscribers a cost-effective method of meeting the collective resilience needs of the transmission grid. The new company houses and maintains long-lead-time critical transmission equipment, such as transformers, in secure storage facilities throughout the country. Grid Assurance also offers pre-planned transportation and logistics support for equipment delivery. As a subscriber, AEP has faster access to both the equipment and logistical support necessary for quickly deploying equipment to an affected location following a catastrophic event.