Cost and reliability comparisons of underground and overhead power lines

This paper outlines the benefits of undergrounding power lines. We present research that reveals the reliability and operation and maintenance (O&M) impacts of electric underground lines relative to overhead lines. This research uses a comprehensive dataset from 163 US electric utilities. Holding the effects of other important operating variables constant, our research indicates that undergrounding reduces O&M cost and enhances reliability by reducing power outage durations. We also provide a brief discussion of other considerations that are important when weighing the benefits and cost of placing power lines underground.

► We model the effect of underground power lines on O&M cost and reliability.
► We find these reduce O&M cost of power distribution.
► They also improve power reliability as measured by shorter outage durations.
► There is a need to balance these favorable effects with the cost of undergrounding.