Erecting the pylons takes a day, rather than a week with conventional types. Daniel Jones/National Grid
Contractor Balfour Beatty is completing a series of six “next generation” electricity pylons being built at the National Grid’s Eakring training academy in Nottinghamshire.
The new T-pylon was adopted by the National Grid after an international design competition – organised by the RIBA and the Department of Energy and Climate Change in 2011 – was won by Danish architect Bystrup.
The training line demonstrates five technical variations in the family of T-pylons – although they look near-identical, each is designed to perform a different function on the transmission network.
The ground works, foundations and erection of the T-pylons at Eakring have been carried out by Balfour Beatty, with steel manufacturer Mabey Bridge producing the monopole and “T” cross section of the pylons as well as doing the final painting of the structure at its factory in south Wales.
The new design is a monopole with a T-shaped cross arm with two hanging diamonds to hold electricity wires. At 35 metres high, it is up to a third lower than the conventional steel lattice pylon.
It is made up of eight main structural components, meaning that, according to the BBC, erection and installation will take a day rather than a week for the traditionally designed pylon.
William McElwain, UK territory director at Balfour Beatty, said: “We’re delighted to be working in partnership with National Grid to deliver this landmark project. As part of the construction process, we’ve supported the development of methodologies and processes to determine the safest way to build all five of the new designs which is a fantastic opportunity for Balfour Beatty. After years of planning, it’s great for everyone involved to finally see the T-pylons become a reality.”
David Wright, director of electricity transmission asset management at National Grid, said: “We’ve been able to answer yes to the hundreds of questions that need to be asked before we can introduce a new type of pylon.
“The training line has enabled us to learn so many lessons about how to manufacture and build the T-pylon. I’m incredibly proud of the high standard of engineering that brought us to this point.
“We developed the new style of pylon so that we could have a 21st century design to offer as we plan new transmission routes. The T-pylon is not a replacement for the steel lattice pylon, but it’s a new option and in some landscapes its shorter height and sleeker appearance can offer real advantages.”
The first use of the T-pylon on the national grid could be to connect Hinkley Point to the grid as part of a new line between Bridgwater and Avonmouth.
The five different proposed T-pylons being built at the Eakring training academy in Nottinghamshire include:
- a standard suspension pylon that is designed to carry the cables in a straight line;
- a D30 pylon which can allow for the greater pressure and weight of turning the cables at an angle of up to 30 degrees;
- an F10 flying angle suspension pylon which can allow a turn of up to 10 degrees – the first time such a pylon has been used in the UK;
- a pair of terminal diamond pylons which end a line at a substation or take the cables underground;
- a gantry terminal which is an alternative design of terminal pylon with the same function as the diamond terminal pylon.