Composites in 2019: Why Are We Still Making Wood Utility Poles?

Every time you turn around it seems like someone is doing something spectacular with a composite material. Take a flight on a Boeing 787 Dreamliner and you’ll be traveling in an aircraft with a fuselage and wings made almost entirely of carbon fiber. Visit any car show and you’ll see composites on full display in wheels, interiors, and entire car bodies.

Knowing what we know about materials like carbon fiber and fiberglass, why are we still manufacturing utility poles with wood? Why is every storm that knocks down power lines followed by an army of utility trucks replacing damaged poles with new poles made from wood?

The tried-and-true wood utility pole has been an American institution for generations. Since the earliest days of electric and telegraph service, wood polls have carried cables from coast-to-coast. Maybe it’s time to change that. Perhaps carbon fiber or fiber glass would be a better choice.

Standing up to Forest Fires

If you’re wondering just how well a composite utility pole would stand up to nature, look no further than a Canadian company that has produced a remarkable pole made with a combination of glass fiber and a specially designed resin. Putting the two materials together produces a fiber-reinforced polymer capable of withstanding forest fires.

Composites Manufacturing magazine reports that the company’s prototype was first tested in a controlled setting in a lab. After passing that test, the company got permission to install their pole in an actual forest and conduct a controlled burn to simulate real-world conditions. Their fiberglass pole performed admirably.

According to Composites Manufacturing, the pole survived the fire without demonstrating any structural failure. The only damage was to the pole’s fire barrier, but even that was minor. The pole even self-extinguished as the fire passed beyond it. That’s pretty amazing.

If you know anything about fiberglass and carbon fiber, you know that both materials are stronger than steel and aluminum. That makes them stronger than wood too. And if they can withstand the punishment of a forest fire, it’s likely the two materials can withstand significant wind as well. They certainly don’t rust, so that’s not an issue.

Composites Are Expensive

So, why are we still making utility poles out of wood? Rock West Composites out of Salt Lake City, Utah says it is probably a cost issue. It costs significantly more to produce utility poles with carbon fiber or fiberglass as compared to wood. To make a wood utility pole, you simply cut down a tree and trim it to size. That’s it.

Making utility poles out of fiberglass or carbon fiber is much more involved. You first have to create virgin fibers, which is time-consuming and expensive. Then those fibers either have to be woven into fabric that can be laid in a mold to fabricate the poll, or they have to be fabricated utilizing a braiding or pultrusion process. At any rate, it’s not cheap.

Next time you are out driving, count the number of wood utility poles you pass along the way. Travel just a few miles and you could easily count hundreds of them. That all adds up. Cities, counties, and states just don’t have the money to replace all those wood poles with fiberglass or carbon fiber.

As great as composite materials are, they have limited applications when cost is a factor. That is not necessarily a bad thing, by the way. Wood utility poles are adequate for their intended purpose. Where wood is not adequate, pole manufacturers turn to steel and aluminum – because they work.