This paper proposes a novel method for transmission network expansion planning (TNEP) that take into account uncertainties in loads and renewable energy resources. The goal of TNEP is to minimize the expansion cost of candidate lines without any load curtailment. A robust linear optimization algorithm is adopted to minimize the load curtailment with uncertainties considered under feasible expansion costs. Hence

the optimal planning scheme obtained through an iterative process would be to serve loads and provide a sufficient margin for renewable energy integration. In this paper

two uncertainty budget parameters are introduced in the optimization process to limit the considered variation ranges for both the load and the renewable generation. Simulation results obtained from two test systems indicate that the uncertainty budget parameters used to describe uncertainties are essential to arrive at a compromise for the robustness and optimality

and hence

offer a range of preferences to power system planners and decision makers.