Benefits of coal-fired power generation with flexible CCS in a future northwest European power system with large scale wind power

Coal-fired power generation with carbon capture and storage (CCS) is projected as a cost-effective technology to decarbonize the power sector. Intermittent renewables could reduce its load factor and revenues, so flexible capture unit operation strategies (flexible CCS) have been suggested to increase profits: CO2 venting and lean- and rich-solvent storage. In this study we quantify the benefits of flexible CCS for both the power plant operator and the total Dutch power system. We use a unit commitment and dispatch model of the northwest European electricity system to simulate the hourly operation of two coal-fired power plants with flexible CCS in 2020 and 2030. We find that flexible capture unit operation hardly affects electricity generation (revenues) because the flexible operation capabilities are not often utilized. CO2 venting is hardly used due to high CO2 prices (43 €/tCO2 in 2020 and 112 €/tCO2 in 2030). The impact of rich-solvent storage is limited because of regeneration constraints of the base-load power plant. The main benefit of flexible CCS is an increase in reserve capacity provision by the power plant of 20-300% compared to non-flexible operation