SUMMARYThe work carried out in this paper is to deal with a proposed conductor temperature rise computation algorithm. This simple algorithm gives more accurate calculation, making use of the load current and the weather data parameters, particularly the amount of solar incidental radiation upon the conductor and the conductor material properties. The calculation is based on the heat transfer mechanisms occurring in the stranded exposed overhead transmission lines (OHTL) conductors in a natural environment. In this paper, the mathematical models for the use of the natural and forced convections are presented by using Numbers of Grashof and Reynolds, respectively, in the determination of the temperature rise of the OHTLs. Skin effect and iron losses are also taken into account in order to determine the alternating current resistance of an Aluminium Conductor Steel Reinforced in the process of iteration's heat balance equation. The surface area factor of the stranded conductors that increases the loss by radiation from the conductor surface is also used to calculate the temperature rise of the stranded OHTL.