Corrosion Management in Ageing Transmission Infrastructures

Abstract

The majority of electric utility infrastructure in North America and across much of the Europe was built from the 1930s onwards using galvanised steel. As these assets age, corrosion is becoming a key risk to the steel structures as metal loss leads to a reduction in structural strength, potential asset failures, reduced system reliability and costly replacement. Engineers are becoming increasingly aware of the corrosion issues faced by their ageing infrastructure, and there is some concern that the depth of understanding and state of corrosion practice across the electric power transmission industry is limited and vary quite widely. Furthermore, because the mitigation of corrosion in electric utilities is based on other industrial applications and not focused on the materials and installations typical to electric utilities, there are some gaps in current knowledge. This study provides an overview of corrosion issues commonly experienced by electric utilities including some ‘best practice’ corrosion risk assessment, mitigation techniques and the business drivers for setting appropriate levels of investment by an electric utility business. Overall, this study demonstrates that while corrosion is an emerging issue for electric utilities, it can be managed effectively using skilled personnel and with some modification to typical industry practices.