The Grid’s Growing Tree Demand

As the world electrifies and expands grid infrastructure, there is suddenly a Paul Bunyan-size demand for trees.

Background: Transmission and distribution are key to transporting electricity from source to user, with most the world’s grid above aboveground sitting atop utility poles. In North America, wood is the preferred material of choice for those poles because of its cost-effectiveness.

• For our Ron Swanson readers, utility poles are typically made using highly-durable douglas fir, western red cedar, red pine, or southern pine. The wood is chemically treated to increase its tolerance to wear from environment and increase its lifespan.

And there’s a lot of poles.

By the numbers: There are an estimated 160 million wooden poles across the continent, most of them built out in the 1960s and 1970s. And much like the polyester leisure suits from the era, they are not aging well.

Wooden poles typically last ~50 years, which is why there are so many that require upgrades right now.

Money doesn’t grow on trees, but the grid will

It’s estimated that 30 percent of transmission lines need to be replaced, which alone could cost up to $1 billion per year. That doesn’t even factor in the cost of required growth of the grid.

Annual spending on the electric transmission system by major US utilities
billion USD

The International Energy Agency predicts that 80 million kilometers of transmission lines need to be added or refurbished by 2040, which could come at a cost of up to $1 trillion by 2050.

In 2019, the US spent $45 billion dollars in new investment and in upgrading their existing system, with roughly $5 billion spent just on utility poles. There has been a clear increase in demand for utility poles with sales doubling over the past decade, paired with shortages that have caused the prices to spike. 

Alternatives: While steel poles or composite poles made with fibreglass and resin are other options for utility poles, they are significantly more expensive.

Direct cost of different types of transmission lines

There is also the option of burying power lines underground rather than having them aboveground. This would protect them from weather events, but it is 10-20 times more expensive.

Wildfire risk: In a hotter and drier world, electricity infrastructure is increasingly causing fires, with the number of wildfires caused by power generation and power lines increased by a factor of 5 over the past two decades. Evidence shows that powerlines were the probable cause of the devastating wildfire in Lahaina earlier this year.

Incidences of US wildfires caused by power generation, transmission, or distribution

Many utility companies are looking to shift from class 4 poles to class 2 poles, which are thicker and stronger, making them better able to withstand increased environmental impacts.

Zoom out: The required expansion and upgrades to the grid will be expensive and rely heavily on natural resources, and very specific resources. With a move towards the larger class 2 poles, the trees used for utility poles will need to be much older, something that can’t just be accelerated with technology.