Here’s an article of interest: https://www.utilitydive.com/news/pge-pacific-gas-wildfires-power-lines-earnings/689272/
Many challenges ahead for PG&E. How fast can they satisfy their critics? Burying lines is taking more time than anticipated especially when compared with covered conductors and aggressive tree trimming/removal.
PG&E states “Based on the type and condition of the equipment, environmental terrain and surrounding fuel conditions, we determine whether to complete undergrounding or another risk mitigation such as overhead hardening,” he said, adding that burying power lines provides the highest level of risk reduction at the lowest long-term cost to customers.”
The “lowest long term cost” or “total cost of ownership” over the life of the asset is the best way to evaluate OH vs UG options.
The industry needs to step-up with better and faster methods of designing and building underground lines. Ideas like the re-use of native materials, slurry backfills, smaller trench width and depth standards, temporary and permanent road and pavement restoration techniques, and the use of above grade cable trays for temporary underground installations that bridge the permit to construction time gap. Let’s be creative.