Nearly a decade ago, BC Hydro, an electric utility serving British Columbia saw that its transmission line stretching across 40 rugged miles along the northwest coast was nearing the end of its useful life. The wooden crossarms supporting the conductors that transmit electricity were beginning to rot. Furthermore, the utility realized it needed a better option to carry the additional electricity required for the region’s growing industry. It investigated a composite solution.

BC Hydro approached Grant Lockhart, CEO of Transmission Innovations Inc. in Vancouver, Canada, who remembers the conversation: “They said, ‘We have a problem. Wood is failing in certain areas along the coast … and steel is increasingly harder to get. It’s expensive, it’s got a huge carbon footprint, it’s heavy, you can’t put it in energized – there is a world of problems with it. Can you come up with an idea that could help us?’”

High-pressure injection molding technology is used to form the GFRP utility transmission crossarms.

High-pressure injection molding technology is used to form the GFRP utility transmission crossarms.

Transmission Innovations proposed a GFRP transmission crossarm capable of carrying up to half a million volts. After performing finite element analysis to prove that the product would support the needs of the new line, Transmission Innovations contracted with Creative Pultrusions Inc., an Alum Bank, Pa.-based manufacturer of FRP composite profiles, to create 24 46-foot long samples for testing at Power Tech Laboratories. The products underwent more than five years of laboratory and real-life applications before approval was given.

The final product, now being installed in the Canadian mountains, features a 6 x 14 x ½-inch C-channel shape for each transmission arm, which range from 46 to 50 feet long. “It is unique that they’re using FRP for transmission arms,” says Dustin Troutman, director of marketing and product development for Creative Pultrusions. “It’s been done in the past, but I don’t think it’s been done to this magnitude or for this size voltage.”