First New Pylons in 90 Years
Pylons are those great steel structures dotted around the country, supporting the overhead cables that carry high voltages of electricity. They make up the UK’s electricity transmission network and started when the first ever pylon was built new Edinburgh in 1928.
Since then, around 88,000 pylons have been built, but a new design hasn’t been constructed in all of that time. With more focus being placed on alternative, non-conventional energy sources, it makes more sense to construct a new type of pylon than try to update those currently in existence.
And this is where the T-Pylon comes in, so-named because of their two-armed shape. In 2011, an international competition was held by the National Grid, which is responsible for the construction and maintenance of pylons and the electricity network.
The winners of the competition would be those who came up with the best new and modern design of pylon. Danish engineering company Bystrup emerged triumphant with their T-Pylon design.
“Our aim was to minimise visual impact and create a design that could adapt well to the English landscape,” said Bystrup’s project manager, Brian Endahl. He explained that pylons of a similar design to the T-Pylon have already been constructed in Denmark, and they were found to work particularly well in hilly areas.
The first T-Pylons have been build in the National Grid’s training centre in Nottinghamshire. At the moment, they are only being used for testing and training, and so haven’t been hooked up to the main grid yet.
To begin with, the new pylons are being used to train staff and contractors. There are certain factors of the new pylons that are very different to the steel pylons, such as the technique used for stringing the cables, or conductors as they are properly called.
You might be thinking that the new towers will make the existing giants become obsolete, but they will, in fact, be working alongside one another. T-Pylons will mainly be used when constructing new power lines in England and Wales, and connecting the new nuclear power station at Hinkley Point to the UK’s electricity network. The main purpose of the T-Pylon will be transferring energy from sources of wind, solar and nuclear power.
The main differences between the century-old pylons and the T-Pylons are their height and shape. While the steel pylons stand at a towering 165ft (50m), the T-Pylon is only 120ft (36m) tall – quite short by comparison.
National Grid CEO Nick Winser believes the new tower design to be a great improvement on the old pylons. He explained that because the T-Pylon is shorter and lighter, as well as the design being so simple, it would fit into the UK’s landscape more easily. “The design of the electrical components is genuinely innovative and exciting!” he added.
The T-Pylons may not be as tall, but they are still capable of operating at 400,000 volts – the same amount as steel lattice towers – because of the way the conductors are held in place. Instead of them being attached to six arms on a standard pylon, a diamond hangs from each of the T-Pylon’s two arms, which can carry the cables off in a much smaller space.
The arms need to be strong, with the ability to carry 60 tonnes, including additional weight that could accumulate from ice on the cables. With only eight main structural components (plus bolts), the new pylons only take a day to build instead of a week like their predecessors. And despite their lighter build, they can withstand wind gusts of more than 80mph (130kph).
Maintenance will also be easier and safer for operators as they will not have to climb the towers to work on them. Instead, they will be able to work from elevated platforms that are positioned alongside the pylon. On top of all this, the T-Pylon will also be more difficult to vandalise because of its smooth and impenetrable surface.
“We developed the new style of pylon so that we could have a 21st-century design to offer as we plan new transmission routes,” said National Grid Director of Electricity Transmission David Wright in a press release.
He concluded by confirming the new pylon wouldn’t be replacing the existing structures. “It’s a new option,” he said. “In some landscapes, its shorter height and sleeker appearance can offer real advantages.”