New technology could help ease the burden of expanding electricity transmission and distribution to meet spiralling demand.
Engineers from the university and EPL Composite Solutions developed an insulating composite cross-arm that can be retro-fitted to electricity pylons to increase their voltage rating.
The devices, which are now manufactured and sold by university spin-out company Arago Technology, have been installed on pylons in some of the most stark and remote areas of the UK to test their resistance to extreme weather and are also being tested for an eventual use with 400kV systems at a coastal site in Scotland.
Tests have also been carried out at the university’s High Voltage Laboratory, which has subjected them to lightning strikes of more than 1.4MV.
The results of the modelling show in some cases the cross-arms are capable of increasing the power carrying capability of a pylon by up to 2.5 times.
Now Arago is planning to install 12 cross-arms with energy companies Scottish Hydro Electric Transmission (SHETL) and National Grid, with a view to further roll-out.
The original aim of the research at Manchester University was to develop an enabling technology to up-rate the operating voltage of existing infrastructure from 275kV to 400kV without the need to replace the pylon towers, but it will also enable smaller towers to be used for new lines.
Another benefit is lower EMF (electro-magnetic field) at ground level.
For the up-rating of existing lines, the composite cross-arm allows tower voltages to be increased without any change to the overall tower structure or height.
All that is required is an upgrade in the conductor to handle the increased voltage.
Significant improvements in power transfer capability can be achieved through the combination of the cross-arm with the use of a low sag conductor to increase current.
“It’s great to see research being translated into solutions for society,” said Professor Simon Rowland, from the University’s School of Electrical and Electronic Engineering, said.
“If the insulated cross-arms can help to connect renewable energy sources with lower cost and less visual impact, everybody will benefit.”