Operating the biggest dynamic line rating network in the UK

Dynamic line rating (DLR) is ideal for increasing wind power transmission capacity and has the potential to make the GB electricity grid more efficient, in the best interests of consumers – and SSEN Transmission are leading the way in implementing the cutting-edge, infrastructure-monitoring technology – now operating the biggest DLR network in the UK.

Over the last few months, the company has installed the technology across over 300km of overhead transmission lines as part of its north of Beauly DLR project, with full operation expected by the end of 2025.

DLR uses real‑time environmental data, including temperature, wind speed, solar radiation, and cloud cover to calculate the true, live capacity of overhead lines. This differs from static line ratings, which are fixed conservative ratings that often leave capacity unused. With DLR, high winds cool lines, enabling higher power voltages to flow safely.

The sensors transmit live conductor temperatures to cloud-based algorithms. The algorithms then calculate real-time and forecast ratings, which are communicated to the National Energy System Operator (NESO), who use the data in making decisions on how to balance generation and manage potential constraint on the network.

And whilst network reinforcement ultimately has a greater impact on increasing capacity, DLR provides a boost to the grid that, working alongside reinforcement, can help to maximise efficiency across the network and cam ultimately save energy consumers money, by alleviating constraints.

Brant Wilson, SSEN Transmission’s Innovation Portfolio Manager, said:
“Operating the UK’s largest dynamic line rating network is a major milestone for us here at SSEN Transmission. It demonstrates our commitment to innovation and unlocking every ounce of capacity from the existing network to accelerate the transition to net zero.

"By making smarter use of the grid, we’re enabling more renewable electricity to flow from where it is generated to where it will be used – and alleviating constraint on the network at the same time too.

“With all sensors now installed, a rigorous period of calibration and monitoring will now take place over the coming months. After that, SSEN Transmission and NESO will work together to perform communication testing, aiming to roll out the system for full operation by the end of the year. At the same time, we’re looking at options for installing more DLR technology across our region."

Watch the installation of DLR technology on our network below: