Most HVAC (high voltage alternating current) transmission lines use technology that was developed in the early 1900’s. The power lines are primarily a core of steel strands wrapped by aluminum strands. These lines are subject to thermal limitations; the lines can overheat, they can sag, and they can break causing power outages and even fires. Because of this, steel core lines are operated at lower loads significantly reducing their transmission capacity. Recent technology relying on advanced conductors uses a stronger and lighter carbon fiber core with outer strands of denser fully annealed aluminum arranged in trapezoidal fashion allowing doubling the current carrying capacity of the lines without the need for new infrastructure or certain permits.

Where pipelines and power lines are collocated in common utility corridors there is a risk from the powerline currents being induced on the pipeline. The resulting increase in power line load capacity could result in electric shock hazards and even AC corrosion.

A case study is discussed predicting the safety and corrosion integrity of a 105 mi long pipeline when the reconductoring program will be executed. A computer model simulates the increase of induced voltage and current density on the pipeline which could not be reduced sufficiently with the existing mitigation system. The impact on the mitigation and monitoring costs is calculated resulting in a significant investment to secure personnel safety and pipeline integrity.