Wind curtailment powered flexible direct air capture

Direct air capture (DAC) has emerged as a pivotal negative emission technology for mitigating climate change. A DAC system integrated with renewable electricity can maximize its carbon capture efficiency; however, the existing DAC systems are incompatible with the intermittency and fluctuations of renewable electricity. This study develops an optimal model aiming to enable flexible operation of the DAC, thereby enhancing the utilization of wind electricity. Transferable and curtailable loads are applied to develop a new operational paradigm for adsorption-DAC systems. A linear programming optimization model is developed to enhance the adaptability of the DAC, ensuring complete utilization of curtailed electricity from wind farms. The case analysis pinpoints the requisite DAC deployment capacity, enabling the nullification of wind electricity curtailment within an actual power profile. Deploying DAC facilities with an annual CO₂ capture capacity of 43,500 tons is likely to eliminate the electricity curtailment of a wind farm of 400 MW in the optimal scenario. Techno-economic analysis indicates that deploying DAC facilities with an annual CO₂ capture of nearly 30,000 tons, along with an impressive 68 % curtailed electricity utilization rate, is the optimal financial choice for the wind farm. This study confirms that the feasibility of flexible DAC operation is essential for coupling with renewable electricity.