Despite Higher Costs, Electric Utilities Increasingly Favor Undergrounding

Update EEI Report Says Aerial Lines Remain Far More Economical
By Jeff Griffin, Senior Editor | December 2013, Vol. 68 No. 12

The question invariably is asked after severe weather or other disasters knocks out electrical power and communications services: “Why don’t they put those overhead lines underground where they’re protected?”
That question has been asked many times in many places over the past few years as heavy winter storms, tornadoes and hurricanes have affected much of the country, knocking out power, communications and other vital services.

Without going to the record books, most people believe the intensity and duration of storms these days are more intense than in past years. In October 2012, Hurricane Sandy alone affected 24 U.S. states, killing 285 people, caused tens of billions dollars of damage and left more than six million customers without power for weeks and in some cases longer.

Immediately after a major storm is not the time to replace aerial plant with underground infrastructure – the immediate need is to restore services. However, for many, the question remains why there is no concentrated effort to replace overhead cable with new cable buried in the ground.

Construction goes underground
For more than 40-years, cable in new residential developments, commercial complexes, educational and government campuses and other facilities have been placed underground.

In older neighborhoods of most American cities, distribution lines – many long past due for replacement – remain suspended from utility poles, often in areas with many trees, and these are the lines usually most vulnerable to wind and ice storms. Even when aerial lines are replaced because they no longer provide dependable service, they often are again suspended from poles, rather than being buried. The reason is simple: cost. Billions of dollars would be required to move existing communications and power cable from up to under. Who would pay that cost?

The Edison Electric Institute (EEI), an association of shareholder-owned electric companies, conducts an ongoing study and gathers data about “undergrounding,” replacing overhead power cable with underground cable. Cost figures in EEI studies relate specifically to power cable, but the methods of placing electric cable and communications cable in the ground are basically the same and it is reasonable to expect cost for undergrounding for each would be similar.

EEI has released Out of Sight, Out of Mind 2012, an updated study of undergrounding overhead power lines. The report was prepared for EEI by Kenneth Hall, P.E., Hall Energy Consulting Inc.