Integrated grid, coal-fired power generation retirement and GESS planning towards a low-carbon economy

To cope with climate change and achieve sustainable development, power systems need a low-carbon transformation. The use of renewable energy and the retirement of traditional coal-fired power plants (CFPP) are two essential transition pathways for power system de-carbonization. How to gradually retire CFPP or install renewable energy generation while maintaining system security and reliability in the energy transition is an emerging yet important research topic. This paper proposes a power grid augmentation planning model based on low-carbon targets, aiming to plan the retirement of CFPP and the installation of renewable energy. In this model, carbon tax is used as an effective limit on greenhouse gas (GHG) emissions. In order to make renewable energy coupled well with the existing grid, gas energy storage system (GESS) is also considered. GESS is an integrated system that combines Power-to-Gas (P2G) technology with hydrogen turbine (HT), which can store electricity generated by renewable energy and reuse it when appropriate. In this way, the system operating pressure is alleviated effectively, and the overall CO2 emissions can be reduced at the same time. In case studies, this paper attempts to find the optimal emission reduction per unit cost by comparing the ratio of carbon emission reduction to total system cost. Based on the numerical results, the proposed model can provide a useful transformation roadmap for the transition towards low-carbon energy grids.