Distribution Line Undergrounding Gaining Traction for Grid Hardening

Distribution line undergrounding is becoming an increasingly popular storm hardening tactic because it shields these lines from falling trees, vehicle accidents, ice accumulation, and high winds to name just a few.  Duke Energy, Florida Power & Light, and PEPCO are examples of electric utilities that are pursuing this tactic, which makes sense given the expected increase in the frequency of severe weather going forward. 

The Push for Distribution Line Undergrounding

Emergency preparedness has always been important in the utility industry, and its importance has continued to increase – there has been an increased emphasis on preparedness ever since Hurricane Sandy battered the East Coast in 2012.  More and more utilities have appropriately increased their focus on training, exercises & drills, cybersecurity, and storm hardening.  And one aspect of storm hardening that is clearly gaining favor is ditching overhead power lines in favor of burying them underground.     

PEPCO, the DC-based electric utility, is the latest to move toward distribution line undergrounding.  In 2017 the DC Public Service Commission (PSC) approved a $500 million initiative to do just that (the initiative was recently reaffirmed by the DC Court of Appeals).  The company has also proposed burying certain transmission lines, and this proposal is currently under review. 

The 8-year distribution line initiative, called DC PLUG, will be paid for in part by ratepayers via the 2017-passed Electric Company Infrastructure Improvement Emergency Amendment Act.  According to PEPCO, which fronted the first $250 million in costs, the undergrounding will improve the reliability of the impacted feeders by a whopping 95%. 

Overall, distribution line undergrounding makes a lot of sense.  And, although it obviously comes at a cost, the price tag for ratepayers is relatively easy to swallow at $1.68 extra per year for the first year, and only $0.60 extra a year each year thereafter.  Definitely a small price to pay for increased reliability!