Introduction: Current overhead line (OHL) ratings are applied on a seasonal basis and do not consider the geographical location of the assets and associated variances in meteorological conditions. As such, line ratings may be unnecessarily constrained, limiting power flows and prompting unnecessary investment for load related upgrades.

Objectives: To reduce the need for load related investment in locations where higher thermal ratings are available due to favourable weather conditions. The scale of this reduction will be determined by the extent to which weather conditions vary dependent on geographical location.