November 11, 2016
When comparing overhead or underground power lines, there are pros, cons and questions. Is it more safe, and less susceptible to damage to place the lines underground? What is the cost difference? Is the additional cost justified? And in the end...what is the best solution for the community?
One of the biggest advantages of underground lines is the protection that they offer from the elements. When installed properly, it's estimated that underground lines can operate for years without issue. With limited exposure to weather and other environmental factors, the risk of damage is lessened, however, when a problem occurs, both the cost of repair and duration of work can be extensive.
Problems on overhead power line can often be easily located and repaired, and simple modifications can be completed quickly, however if a storm is too strong for repairmen to work through, and outages mount, repair timelines increase with the sheer amount of work.
Locating a problem underground is much more difficult and time consuming compared with overhead lines, and once a problem has been located, the labor cost is different and the amount of work required is greater.
Cost varies greatly between the two types of lines. Initial costs of underground lines are significantly more than that of overhead lines; the difference in each state is about five times greater for underground than overhead. Regardless of underground line reliability and improved technology, the installation costs remain high due to the labor required to trench the area during installation. An argument can be made that cost-savings come into play as underground lines should not require repairs for several years after installation.
Cost of Repair and Maintenance
The cost to repair underground lines can be up to ten times more expensive than the more easily accessible overhead lines.
An article by Frank Alonso, P.E. and Carolyn A. E. Greenwell, P.E. on Electric & Power's website explores the cost comparison:
"'They can be, but it's expensive,' is the proverbial answer concerning underground power delivery, but the time is quickly approaching when utility customers and government officials will demand an answer that provides a more in-depth, independent look at how much more expensive underground power delivery is compared with overhead power delivery. Changes will be precipitated by power outages associated with natural disasters, citizens who don't want their homes devalued by nearby overhead lines, and competitive economic forces that drive utilities to consider placing power lines underground."
Click here to read the entire article on the Electric Light & Power website.