Multiobjective generation expansion planning considering power system adequacy

•A multi-period multiobjective generation expansion planning model is presented.•The model simultaneously optimizes three objectives: costs, emission, and reliability.•A probabilistic approach is implemented to evaluate the system reliability.•A MNBI method is proposed to solve the multiobjective problem.

A Multi-period Multi-objective Generation Expansion Planning (MMGEP) model incorporating sustainable energy sources is presented in this paper. The proposed model simultaneously optimizes three objectives: costs as well as environmental impact minimization, and reliability maximization. The optimization model decides the optimal size, time and technology types of the generating units through a multistage planning horizon. An analytical probabilistic approach is proposed to evaluate the system reliability of long-term planning period. In this paper, in order to identify Pareto optimal solutions of the MMGEP problem, a Corrected Normal Boundary Intersection (CNBI) method is implemented. A lexicographic optimization method is employed to improve the performance of the NBI method. A synthetic test system including seven types of candidate units is considered for MMGEP in a 6-year planning horizon. The results of CNBI method are compared with those of the classical weighted sum and ordinary NBI methods.