Composites can help the U.S. build a stronger infrastructure capable of withstanding nature’s blows.
Hurricanes, wildfires, floods and tornadoes battered the U.S. in 2017, inflicting millions of dollars in damage on roads, bridges, power grids and other infrastructure. While that repair bill is high, it’s only part of the story. To get the infrastructure in good shape, the American Society of Civil Engineers (ASCE) estimates that the U.S. would have to spend $4.6 trillion by 2025 to make the necessary repairs and replacements.
The use of composite materials can help the country get the best value for its investment – and it’s not just industry insiders who are saying that. In testimony to Congress in April 2018, Joannie W. Chin, deputy director of the engineering laboratory at the National Institute of Standards and Technology (NIST), enumerated composites’ advantages. “Advanced composites are often stronger, lighter, and longer lasting than traditional building materials, thereby offering many cost savings,” she said. “The longer lifespans for infrastructure components that include advanced composites mean fewer service days lost to maintenance of the bridges, roads, dams, levees, highways, railroads, utility poles and other elements that support movement of the goods and services that underpin our economy.”
Hurricanes, ice storms and high winds frequently bring down wooden telephone poles, cutting power to thousands of homes and businesses. Resilient FRP poles help utilities keep the lights on.
There are many examples. When Hurricane Odile hit Mexico’s Baja Peninsula in 2014, only the electric lines that had been hardened by replacing every fifth wood pole with an FRP pole remained standing. In the Grand Bahamas, hurricanes in 2011 and 2015 took out 2,700 wooden poles, but all 450 composite poles the utility had installed remained intact.
Composite poles are more environmentally friendly, don’t require the use of chemical preservatives like creosote and are easier to install in difficult-to-access locations. Highland Composites, for example, makes FRP poles in 13-foot sections that can be joined together on site, eliminating the need for cranes to lift heavy wooden poles into tight places.
Composite poles cost two to four times more than wooden poles, and that has discouraged many utilities from installing them. But FRP poles have a lifespan of 60 to 80 years, twice that of a wood pole. In the long run, power companies that use FRP poles save money because they’re paying installation costs only once in 60 years instead of twice.
But utilities tend to use much shorter time frames when figuring costs, so they usually overlook that equation, according to Scott Holmes, director of business development, Highland Composites. “Utilities are more receptive to looking at some of the other benefits, like the environmental ones or hardening the grid against future storms,” he says. “They may also look at a case where using a composite pole will make installation safer and easier because the location is difficult to access.”
Direct comparison of fiberglass and wood poles is difficult because they are measured or rated by different standards. FRP pole manufacturers use ASCE 111, Reliability Based Design of Utility Structures, which rates a material’s strength based on its variability. It’s the same standard used for rating composite materials for bridges and other building applications. Wood poles, however, are measured on their average mean strength, which is expressed as a class rating. To make comparisons easier, ACMA’s Utility and Communication Structures Council has developed a wood equivalent class rating system for composite poles.
The FRP pole market could get a big boost from a recent decision by the Federal Emergency Management Agency (FEMA) in the U.S. Virgin Islands. FEMA has previously allowed recovery funds to be spent only for a like-for-like replacement – a wood utility pole for another wood pole. But after reviewing the performance of FRP utility poles in recent hurricanes, FEMA agreed that federal funds could be used to replace several thousand wood utility poles with composite poles. “That really is unprecedented,” Holmes adds.
News about the superior performance of FRP poles is spreading. After a 2017 windstorm cut power to more than 170,000 customers in Rochester, New York, the utility companies there signed an agreement with the New York State Public Service Commission to improve their infrastructure. They will be spending $1.25 million to replace many wooden utility poles with the stronger, more resilient fiberglass poles.