TY - JOUR AB - Purpose The purpose of this study is to address the efficiency of power losses representation while still reducing the computational burden of an optimal power flow (OPF) model in transmission expansion planning (TEP) studies.Design/methodology/approach A modified TEP model is formulated with inclusions of linearized approximation of power losses for a large-scale power system with renewable energy sources. The multi-objectives function determines the effect of transmission line losses on the optimal power generation dispatch in the power system with and without inclusion of renewable energy sources with emphasis on minimizing the investment and operation costs, emission and the power losses.Findings This study investigates the impact of renewable energy sources on system operating characteristics such as transmission power losses and voltage profile. Sensitivity analysis of the performance for the developed deterministic quadratic programming models was analyzed based on optimal generated power and losses on the system.Research limitations/implications In the future, a comparison of the alternating current OPF and direct current (DC) OPF models based on the proposed mathematical formulations can be carried out to determine the efficiency and reduction of computation process of the two models.Practical implications This paper proposed an accurate way of computing transmission losses in DC OPF for a TEP context with a view of achieving a minimal computation time.Originality/value This paper addresses the following objectives: develop a modified DC OPF with a linearized approximation of power losses in TEP problem with large integration of RES. Investigate the impact of RES on system operating characteristics such as transmission power losses and voltage profile. VL - 18 IS - 5 SN - 1726-0531 DO - 10.1108/JEDT-11-2019-0291 UR - https://doi.org/10.1108/JEDT-11-2019-0291 AU - Gbadamosi Saheed Lekan AU - Nwulu Nnamdi I. PY - 2020 Y1 - 2020/01/01 TI - Optimal planning of renewable energy systems for power loss reduction in transmission expansion planning T2 - Journal of Engineering, Design and Technology PB - Emerald Publishing Limited SP - 1209 EP - 1222 Y2 - 2024/04/24 ER -