Lately, Vaidya has seen a trend toward reinforcements beyond typical ECR glass fibers to adjust the modulus of elasticity of composites. “Here, pultruded sections reinforced by high-modulus glass fibers or fabric composites enable a step change for composites performances,” he says.
In addition, polyurethane-based resin systems are emerging as a popular resin choice alongside polyester and vinyl ester resin systems. “We’re seeing this resin being used because of the benefits that material offers in terms of damage resistance as compared to other types of systems, including polyester and vinyl ester,” Vaidya says.
Ultimately, Haddad predicts, closer collaboration with the client could simplify the specification process for FRP utility poles. Currently, a specification may just note an ANSI-required pole tip circumference that’s largely irrelevant for FRP poles. “We’re hoping [in the future] they give us a groundline requirement and a deflection requirement in terms of inches per thousand pounds so that it’s truly an apples-to-apples comparison among the competitors that make composites distribution poles,” Haddad says.
Hurricane Grid Hardening
Of course, fires aren’t the only disaster that have led utility companies to consider grid hardening. In 2005, Hurricane Wilma damaged about 12,000 utility poles across Florida. Utilities in the state began moving some lines underground and switching to composite and concrete poles. Even so, more grid hardening is required as 2018’s Category 5 Hurricane Michael took out more than 6,800 utility poles in the Florida panhandle.
There’s ample evidence that FRP poles can stand up to high winds. RS Technologies installed about 500 poles in a 69kV transmission line in the Bahamas a decade ago. “That line took a direct hit from Category 4 Hurricane Matthew in 2016,” Fecht says. While Grand Bahama lost several thousand wood poles to the 140 mph winds, there was no damage to the composite structures, which were designed to withstand 150 mph winds.
Last year, RS Technologies was called in for a new project to support the island’s grid resiliency. The fabricator provided a small line of poles to connect a new solar farm and battery depot to Grand Bahama Power’s main substation. Shortly after completing that project, Hurricane Dorian devastated the island. Not only did the new project withstand the sustained 160 mph winds, but so did the initial 500-pole line.
Today, RS Technologies is replacing nearly 9,000 poles in the U.S. Virgin Islands. “FEMA came in and said if we’re going to rebuild, it’s going to have to be different than wood because we keep replacing wood poles that have failed in hurricanes,” Fecht says.
Installation Cost Case
FRP poles remain popular in areas where their benefits have already been proven. “There’s always going to be that need for limited access areas and woodpecker-prone areas where utilities want to be proactive and put composites in,” Troutman points out.
What is changing in those areas, however, is that utilities are now less likely to balk at the higher upfront cost of FRP poles. They’ve already seen the healthy return on investment in composite poles and crossarms.
“There are a number of utilities we work with that, as soon as they have a woodpecker hole, that pole comes out and a composite pole goes in,” Fecht says. The reason? Installing a $500 wood distribution pole might ultimately cost closer to $13,000. That includes higher costs for equipment to install wood poles, plus future maintenance costs of sending out crews to inspect and patch woodpecker holes at easily $1,000 per hole. And because the conductor-induced vibration of a wood utility pole suggests to woodpeckers that there’s insect activity inside the pole, one hole quickly leads to dozens more. Those costs rise fast.
The case for return on investment is also being made in difficult-to-access instances. Fecht cites an example of an installation in Australia where the utility had planned to build an $80,000 road to move heavy equipment in and replace a single wood utility pole. “You can rent a helicopter for a day for a lot less than $80,000,” Fecht says. While it may seem counterintuitive, the ability to transfer lightweight composite products by helicopter has demonstrated tremendous cost savings.
An installation of 140 H-frame structures for a Scottish and Southern Electricity Networks wind farm transmission line connection in northern Scotland also demonstrated how helicopters could lead to savings. The installation of these 90-foot FRP structures took only three days, with a cost of $16,500 per hour of helicopter use. It’s a tough number to swallow, until calculating the cost of months of transporting massive wood structures across the difficult terrain. In addition, the line was completed well ahead of schedule, allowing the line to be energized and deliver revenue sooner.
Crossarms have also helped make the cost case for FRP transmission and distribution structures. “A majority of utilities have now adopted composite crossarms in place of wood,” Schoenoff says. “They get significant grid hardening benefits in addition to a much lower total ownership cost due to the improved service life of fiberglass crossarms.”
“There’s probably more of a turn across the nation away from wood and toward FRP crossarms than has been seen in the last 20 years,” agrees Jim Bob Wiles, senior manager, Valmont Composite Structures. “I dare say that in 10 years wood will be in lower usage compared to fiberglass.”
As Wiles points out, crossarms have now had over a decade to prove their cost benefit: “FRP crossarms were introduced in 1992, and it takes 20 to 25 years before utilities believe that it really works. That’s where we are now.”
New Competitors
With composite products suddenly becoming mainstream for utilities, long-time FRP crossarm and pole manufacturers are finding the market is filling up with a new competitor — first-time FRP manufacturers. Long used to defending their product against steel and wood, the experienced manufacturers are now educating end users on exactly what makes a reliable product.
“Across the whole composites industry, whenever there’s a market that sees a bubble – and that goes from bathtubs to boats – we get people coming in that don’t do such a good job,” Wiles says. “It muddies the water, and that’s why fiberglass composites, frankly, get a bad name.”
As Fecht points out, when a utility specifies a wood pole, they can go to lots of suppliers and get virtually the same product. “They might have some subtle differences in how they treat them, but those poles all come from the forest,” he says. “But with composite materials, when you ask for that 50-foot Class 1 pole, you can get that from any number of manufacturers who use different manufacturing methods, different raw material inputs, including different resin systems, and you can end up with very different products under the same broader category and a resulting range of performance across many dimensions.”
Fecht works to educate end users on factors that can undermine an FRP pole’s durability, such as insufficient UV protection that could lead to structural deficiencies due to resin loss from fiber blooming. Meanwhile, manufacturers across the board continue to adjust formulas to further strengthen their products. “There’s been a focus now for several years on increasing the reliability,” Troutman says.
The case has already been made that FRP might be the right solution for more jobs than previously imagined. As Fecht puts it, “Ten or 15 years ago we were saying, the pole can do all these great things and utilities were looking at it and looking at the price and saying, ‘Sure, but give us some examples.’ Now with installations on all five continents, we can say, ‘What about this in the Bahamas and this in Scotland and this in Norway and this in California?’”
