Abstract
In an ever increasing power system, it is one of the major challenges to make a balance between load and the generation especially in unbundled or deregulated power systems. At the same time the enhancement or expansion of the transmission system becomes a critical factor while balancing later two. There are several approaches given in such an environment based upon different constraints, in this paper one of the approach which is based on MW-mile method is used which utilizes economic index approach as an optimization factor for the transmission expansion.