Using numerical weather forecast to predict power losses on transmission lines

The paper presents the first version of a method developed to forecast resistive power losses associated to transmission lines. In the first stage the procedure computes the conductor temperature, taking into account a non-steady-state heat balance equation. The terms of the heat balance are evaluated using as input data the numerical weather forecast combined with GIS mapping of the line assets, and the day ahead hourly forecast of the power flow. The resulting conductor temperature is then used to correct the value of the electrical resistance and finally to evaluate the resistive power losses. The method was applied for two existing 400 kV transmission lines, and several forecasts obtained for the conductor temperature and specific power losses are presented.