OHL assessment and risk evaluation based on environmental and inspection data

•LiDAR inspection data provide input to characterize OHL spans.•Grid and environment data centralized in geo-referenced database.•Risk models calculating severity and fault probability for circuits were developed.•Results for short and medium term used for operation and planning.

REN – Rede Eléctrica Nacional, S.A., Portuguese Transmission System Operator (TSO), has been using LiDAR technology in their aerial inspections. The acquired three-dimensional data in this Power Line Maintenance System are automatically processed, with support of the video inspections and geo-referenced systems. The national transmission grid was fully characterized at span level with urbanization and vegetation growth rate indices.The collection of historical data, together with the knowledge of asset characteristics and system operation conditions, is structured in a generalized relational database, extended with a comprehensive set of different environmental, meteorological and geographic data over the years.A methodology to evaluate operational risk was developed, taking into account the probabilistic nature of contingencies and their severity under specific operating conditions. Risk indices provide an insight to operators of the network state and of the constraints that operators face. Different optimization tools are also being developed.