Leading the way on dynamic line rating
A blog, first published in Utility Week, by SSEN Transmission’s Innovation Portfolio Manager, Brant Wilson.
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 at SSEN Transmission we’re leading the way in implementing the cutting-edge, infrastructure-monitoring technology.
As part of our North of Beauly DLR project we are installing the largest DLR system in the UK, with full operation expected by the end of 2025. There is real alignment between wind power and the technology, making it ideal for maximising network efficiency in areas where it is windy. Put simply, the higher the wind speed, the better - as it cools conductors down, which in turn, allows us to increase the amount of power flowing through the line.
How does it work?
DLR uses sensors to monitor power lines, taking into account environmental temperature, wind speed, solar radiation, and cloud cover to determine the maximum amount of power that can be safely carried, without making conductors sag beyond our safety standards.
Our pilot project covers the network between Beauly and Dounreay, covering 10 circuits. Currently 42km of DLR has been installed on our network between Connagill and Gordonbush. Soon though, our DLR network will cover more than 300km of network – across the ten circuits – which will make it the largest system of its type in Britain.
Sensors installed on the lines send data about conductor temperature into a cloud-based algorithm which calculates the real-time conductor rating, and forecasted rating. This dynamic rating is then communicated to the National Energy System Operator (NESO) and is then considered as part of NESO’s operation of the balancing mechanism and generation constraints.
DLR installation on high voltage electricity infrastructure in the north of Scotland
And whilst network reinforcement ultimately has a greater impact on capacity, DLR provides a boost to the grid that, working alongside reinforcement, can help to maximise efficiency across the network and ultimately saves the energy consumer money, by alleviating constraints.
“DLR and reinforcement work go hand in hand. DLR can provide you with extra capacity – that boost – but you still need reinforcement projects and to build out the network to accommodate the country’s needs.”
And the best way for DLR to have a positive impact for everyone in the GB market, would be for the three GB transmission operators to continue working on a collaborative approach, led by NESO, aligning on a system that would see the technology being implemented across the electricity grid further, in a way that would provide one consistent set of data for NESO to work with in managing the flow of power.
So far, DLR technology has been relatively low-cost to install, with sensors being fitted by teams using mobile elevated work platforms in the field, requiring short-term power outages – but as the technology evolves, it is likely that installation will be carried out by drones on live wires, without the need to any interruption to power supplies.
What else could we do with DLR?
In a perfect engineering world, when identifying the optimal routes for new overhead transmission lines, you could pick the most-rating preferable route – although selecting overhead line routes already comes with a number of factors that need to be balanced, but DLR optimisation is something that could come into play in the future.
What’s certain is that at SSEN Transmission we’re really keen to keep leading the way with DLR, and work with partners across the industry to make sure that we embrace the opportunity that comes with the technology.