pwr_october-2023 - 36

TRANSMISSION & DISTRIBUTION
The Benefits of Fiber-Reinforced
Polymer in Power Transmission
Wood, steel, and concrete are commonly used materials for power poles. However,
fiber-reinforced polymer (FRP) offers a relatively lightweight, safe, and resilient
alternative, which also offers a long service life.
Dustin Troutman
s humans try to move toward
" greener " pastures to combat
climate change, our power grid
is under immense strain. The U.S. grid
got its last major overhaul more than 70
years ago, and these now-ancient poles
and lines simply cannot step up to the
challenge of increasing electrification.
A boom in electric vehicles and a surge
in 5G build-out ask more of our power
infrastructure and utility poles than they
can handle, even without the destruction
of an increasing number of severe
weather events.
Beyond ever-present shortages of
funding and labor, grid modernization
must face nature's supply chain problem:
trees for high-strength poles. Let's look
at what's happening with wood first.
Then, let's consider how, as power professionals,
we've got to expand our toolbox
to include composites.
A
in greater live and dead loads that can
support our electrification plans and can
survive more-severe thunderstorms, hurricanes,
wildfires, and more. This means
not just more poles but stronger ones.
Table 1 shows the American National
Standards Institute's (ANSI's) pole class
ratings and their traditional suitability.
Pole materials are more varied now, but
ANSI ratings are based on wood, the
only available material for poles originally.
But the realities behind this chart
are changing.
Storms especially have gotten meanMore,
Stronger Poles Needed
The modern power grid has to factor
Class
10
9
7
6
5
4
3
2
1
H1
H2
H3
H4
H5
Table 1.
Horizontal Load
(in pounds)
370
740
Telecom
1,200
1,500
1,900
2,400
3,700
4,500
5,400
6,400
7,500
8,700
Suitable for...
er. They hit our power grid with more intensity
than traditional Class 5 or 6 poles
can handle. The answer has been either
to increase the number of lower-class
poles or to upgrade to higher-class ones.
Even distribution poles can sometimes
approach Class 1 or H-class, and transmission
poles have mostly moved into
the H-classes from Class 1, 2, or 3.
Because of this move to higher classes,
a second problem emerges: wood
supply. Wood utility poles can come
from only certain tree types and heights.
Suitable trees make up less than 10% of
the average forest. A single tree needs
more than a quarter century to grow to
usable size, and even then, some will
be disqualified for utility use due to size
or qualities. And this doesn't even consider
the demand for high-strength, longlength
poles for non-utility industries.
This is why, especially for transmission,
utilities have largely transitioned
to steel. The American Iron and Steel
Institute's 2013 life cycle assessment
(LCA) study stood steel and wood up
against each other and found steel often
outperforms wood on durability and environmental
impact. Other utilities have
looked to concrete for a solution.
The massive overhaul our grid needs
requires that we arm ourselves with
as many tools as possible to meet the
demand for stronger, safer, more sustainable
utility
poles. Fiber-reinforced
polymer (FRP), a composite, is another
available option that is up to the challenge
of even power transmission.
Distribution
3,000 Distribution and
Transmission
Transmission
10,000
The data in this table is taken
from the National Wood Pole Standards.
Source: Nelson Research
36
1. To use the chart, locate the desired wood strength classification, class, and length. The color
of the box corresponds to the equivalent fiber-reinforced polymer (FRP) pole. For example, if you
required a 70-foot Class H2 ANSI 05.1/GO95 pole, the red box indicates the 16-inch diameter
TU460 pole as the equivalent. Creative Composites Group is constantly expanding its offerings
to meet market needs, which is why an 18-inch pole will soon be available. Courtesy: Creative
Composites Group (CCG)
www.powermag.com
POWER | October 2023

http://www.powermag.com

PWR_ October-2023

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