Staggered FRP Poles Strengthen Ameren’s Grid

High-speed, straight-line winds and tornadoes are regular events in the Midwest, with winds often exceeding 100 miles per hour. Winds this strong can rip wood poles from the ground or snap them. As a pole falls, it takes its power line with it, which can pull other poles down in what forms a “cascading outage.” A cascade can create days and days of overtime work as line crews work as quickly as they safely can to restore the lines. Costs double or triple when this work has to occur in active storm conditions. Ameren needed a solution that could minimize cascading outages. Or eliminate them.

Ameren chose the single-layer TridentStrong pole with a 14-inch diameter for poles 60 to 70 feet and 15 inches for poles over 75 feet. Ameren also uses TridentStrong multi-layer poles at corners, dead-ends and other unguyed locations where needed.

Fiber Reinforced Polymer (FRP) was the ideal solution: significantly less conductive and lighter than steel but more resilient than wood. They have an excellent modulus of elasticity and are nonporous and non-corroding, allowing them to bend and flex under high winds and to have a longer service life.

But these benefits came at a higher initial cost than wood. So Ameren came up with a “staggeringly” creative solution: installing a TridentStrong pole every fifth pole. By integrating a more resilient pole in between the number of poles a line crew could safely install in a day, Ameren hoped to reduce any cascading outage to a single day’s work.

It was a resounding success. Tested by nature, the staggered composite poles remained standing between wood poles that had bent over or snap. The TridentStrong poles have withstood straight-line winds, terrible ice storms and tornadoes that have taken out wood poles along the 20-mile spans Ameren hardened with FRP. The poles show no signs of age after 10 years installed, evidence of their superior total cost of ownership.

Even better, the poles are sourced from CCG’s Granite City facility, so Ameren can support a hometown business.