Environmental shutdown of coal-fired generators for greenhouse gas reduction: A case study of South Korea

•Hourly economic dispatch problem with annual CO2 emission constraint is solved.•The problem is complicated due to two different time horizons.•Environmental shutdown method is proposed to find the near optimal solution.•It is confirmed that the proposed method works well for large-scale power system. Recently, concerns about greenhouse gas reduction in the power generation sector have increased significantly. The introduction of environmental economic dispatch is being discussed in depth, particularly in countries where there is insufficient investment in fundamental greenhouse gas mitigation measures, such as renewable energy, or carbon capture and storage. The most significant problem with the existing environmental economic dispatch studies for greenhouse gas reduction is that they do not consider the time horizon difference between the greenhouse gas emission target (allocated on an annual basis) and environmental economic dispatch formulation (optimized on an hourly basis). Most of the existing environmental economic dispatch studies assume that hourly greenhouse gas emission targets are given, or if they are formulated as an annual optimization problem, they only deal with relatively small systems. In this paper, we propose a novel environmental shutdown method that can find the near optimal solution to the environmental economic dispatch problem for greenhouse gas reduction, simultaneously considering the hourly allocation problem and environmental economic dispatch optimization. In order to verify the effectiveness of the proposed method, it is applied to a large-scale power system with actual system and technical parameters. As a result, the proposed method is considered to be one of the effective methods of environmental economic dispatch that can be used to achieve short-term greenhouse gas reduction targets in countries where investment in renewable energy is not sufficient.