To accommodate the intermittent renewable energy sources in existing power systems, the expansion of networks, storage integration, back-up capacities and efforts for a flexible consumption are required, otherwise grid can be overloaded. The transmission expansion planning (TEP) has the purpose to ensure two important objectives: economic trade and engineering reliability. TEP can increase the competitiveness of the market participants, providing the reliability and safety of the power grid. In this paper, TEP problem is formulated for establishing the optimal decisions in a large real network with classical generators and high share of RES to minimize load-shedding costs and to facilitate energy exchange between consumers and producers. The analysis results were obtained considering the variation of investment budget for a certain number of new transmission lines.