Survey of power system planning models and optimization techniques

Power system planning is important for technical and economic efficiency and adequacy of future electricity networks. The expansion of the power system is a challenging problem due to its large-scale, long-term and non-linear nature. Since the computer science revolution, there are several emerging techniques proposed to solve power system optimization problems. This paper will present an overview of existing power system planning approaches and optimization techniques, published in the international technical literature. Subsystems and systems with short-term time horizon (years) have been successfully solved. However, it still remains a hard task to solve large-scale systems in a dynamic way with a long-term time horizon (decades). Recent developments in the electricity system even further increase the complexity of planning in the electricity sector (e.g. liberalized market, unbundling of vertically integrated energy companies, and ongoing energy transition). In addition, many stakeholders are involved with multiple objectives of interest, sometimes also conflicting. Appropriate multiobjective planning methods that consider these aspects can reduce investment risks for different stakeholders (e.g. network operators), which eases the integration of renewable energy sources and maintains a reliable electricity supply. However, this has not been done so far.