Climate change a growing problem for power network

Criss-crossing the south of England are the thousands of miles of overhead cables bringing power to homes and businesses.

Keeping those lines clear of trees and vegetation is a never ending task for power distributors like Scottish and Southern Electricity Networks (SSEN).

The company is spending £25m a year surveying and clearing its lines.

With climate change meaning longer growing seasons, the company that supplies power across Hampshire, Dorset, the Isle of Wight, Berkshire and Oxfordshire, says it is likely to become a bigger problem.

Resource & Scheduling Manager Russell Turner explains: "On average, I think we forecast back in 2021, it was 1.2m of growth per year.

"And that is only going to increase with climate change going the way that it's going.

"Growing seasons seem to mean that we're experiencing larger growth and of course we need to cut more to stay on top."

SSEN is responsible for around 40,000 miles (64,267km) of overhead lines across the region.

Each span, the distance between poles, is checked every three years for tree growth and obstructions.

The south has the most densely vegetated network.

During the past two years, teams have surveyed 190,000 spans - the equivalent to 9,500 miles (15,288km).

Out of those spans checked, 114,000 were identified as needing cutting.

Jack Perrins is a Quality Safety Inspector. He is one of a team of 20 line walkers who physically check each span.

"I do about 20,000 steps a day," he says.

"In the summer you can get out a bit earlier, it's lighter because you can't really do this job in the dark.

"I came from a tree cutting background so I understand the trees and I'm still outside, I'm still enjoying it."

By walking the length of a line, Jack can spot problem areas as well as talk to landowners and identify access issues for cutting teams.

"The best way to do it is on foot," he says.

"So although we do have Lidar, they don't pick up what is on the ground, what needs cutting, what the ground conditions are like. The best way to do it is on foot."

The information gathered by the team of line walkers is ed on to utility arborists like Archie-blu Cupper: "We will have a circuit which we are given and we will work our way through that circuit.

"We will start at one pole and then work our way through the entire line. Some of them can take weeks - it depends on how bad the growth is.

"Once we are done with one circuit we will move on to the next circuit in the area and we're basically moving around chasing our tail essentially."

Three point one million customers rely on SSEN's network in the south.

If power is lost due to a fallen tree the company faces penalties from the regulator Ofgem.

According to the distributor, recent investment in line clearance has seen a 20% reduction in power cuts over the past 12 months.

For the teams on the ground access to the power lines isn't always straight forward.

Whilst the company has emergency powers to get onto land to fix lines brought down by trees, day-to-day maintenance can prove more challenging.

"Land owner refusals is a big one – people don't want us on their land cutting their trees," says tree cutting manager Gary Ellcome.

"Crops in farmer's fields is a bit of a problem.

"We have got to time cutting around that and a big one is bird-nesting season so we've got to be really careful."

While technology is being developed to use satellites to identify tree species and monitor power lines, for now line walkers like Jack will continue to follow the network wherever it takes them.

He says where the cables go the line walkers follow: "Over barbed wire fences, over ditches, rivers – we'll find a way and walk the route.

"You go through many a sock."

You can follow BBC Hampshire & Isle of Wight on Facebook, X, or Instagram.