SSEN Transmission has activated dynamic line rating (DLR) north of Beauly, creating the first DLR-enabled circuit on its transmission network in the north of Scotland and unlocking additional capacity on existing lines.

DLR allows transmission operators to optimise the use of current infrastructure by assessing in real time how much electricity overhead lines can safely carry. By increasing available capacity when conditions allow, it helps cut network constraint costs that ultimately feed through to consumers' bills.

Constraint costs arise when the grid cannot transport all the electricity being generated, meaning some output—often from wind and other renewables—must be curtailed. SSEN Transmission is tackling these costs through targeted engineering measures now, while also investing in long-term network upgrades to drive them down further.

In 2025/26, the company delivered nearly £300m in savings for electricity consumers, largely through reduced constraint costs.

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Over recent months, SSEN Transmission has installed DLR equipment on more than 300km of overhead lines between Beauly and Dounreay, and the north of Beauly project is now fully operational.

Traditionally, overhead lines run to static ratings. In practice, weather conditions often permit higher safe power flows. DLR uses live environmental data—such as air temperature, wind speed, solar radiation and cloud cover—to calculate true, real-time capacity. For example, stronger winds increase cooling on conductors, allowing ratings to be adjusted and power flows raised when safe to do so.

Sensors fitted to the network feed data to specialist software that determines how much electricity can be transported at any moment. This information is shared with the National Energy System Operator (NESO) to support real-time management of electricity flows across Great Britain.

While large-scale upgrades ultimately deliver the biggest step-ups in capacity, DLR provides a valuable, immediate boost that improves efficiency across the grid.

Building on this milestone, SSEN Transmission is preparing to deploy live-line drone installation of monitoring sensors as DLR is rolled out to other optimal locations on its network.

Dave McKay, Network Director, SSEN Transmission, said: "This is a major milestone in SSEN Transmission's delivery of innovation and efficiency in the electricity grid - the first DLR-enabled circuit on the transmission network in the north of Scotland.

"Making the best possible use of the existing network, alongside investing in grid upgrades, is helping us reduce costs for consumers while supporting Scotland's energy security and clean power ambitions."