Dynamic Thermal Rating

Dynamic Thermal Rating

Dynamic Thermal Rating is an international award winning engineering scheme that will enable us to increase the amount of renewable wind generation connected to our network. This innovative solution will enable our existing network to be operated more efficiently and facilitate quicker and more cost effective network connections for wind farms.

The principle behind Dynamic Thermal Rating is the measurement and calculation of the cooling effect that meteorological conditions have on overhead lines the same meteorological conditions that are a prerequisite for wind generation.

During normal operation, current passing through the lines creates heat which in turn causes the line to sag, the network is therefore designed up to a defined line temperature so that the lines do not sag excessively, e.g. 50?C. At present the rating of the lines to transmit electrical energy is calculated using the heating effect of the current it transmits offset by the cooling effect of assumed static meteorological conditions, e.g. wind speed 0.5m/s, ambient temperature 20?C (summer). When ‘real time’ meteorological conditions are utilised in the same calculations it is possible to obtain a rating of 150% of the lines traditional rating that occurs in sync with times of maximum export from the wind farms.

Over the next 2-3 years we are delivering a large scale trial of Dynamic Thermal Rating on our 132,000volt network in North-Wales utilising the Ofgem Low Carbon Network Fund. Its aim is to deliver an industry leading operational scheme that will increase the connection of renewable wind energy in North-Wales and the necessary learning for similar schemes to be rolled out across the UK.

Our New Dynamic Thermal Rating Brochure is Available to Download

Ashton Hayes Brochure</a> (2.3Mb pdf)