Flexible operation of solar-assisted carbon capture power plants considering interval-enhanced CVaR

Abstract

Solar-assisted carbon capture power plants (SACCPPs) leverage solar thermal energy to mitigate power output loss and expand the net output range of carbon capture units, enhancing energy economy, reserve capacity, and carbon emission reduction. However, assessing the flexible operation benefits of SACCPPs in power systems with high wind power penetration is challenging due to complex thermodynamic models and limited risk assessment methods. This study addresses these gaps by proposing an innovative modeling approach and benefits evaluation framework. First, a linear flexible operation model is developed, focusing on the technical features of SACCPPs relevant to power system operation and scheduling. This model elucidates the intercoordination in power generation, carbon capture, and thermal storage. The operating ranges of various carbon capture power plants are quantitatively analyzed using a two-dimensional coordinate diagram, highlighting the flexible regulation advantages of SACCPPs. Second, an Interval-Enhanced CVaR method is introduced, which considers random variables with unknown probability distributions, refining the current CVaR-based knowledge. This method is used for a quantified risk assessment to evaluate supply-demand imbalance risks in power systems, providing a foundation for assessing SACCPPs' risk mitigation benefits. Third, a risk-aware operation scheduling model is developed to explore SACCPPs' capability in enhancing the system's energy economic benefits, risk mitigation, and carbon emissions reduction. This model aids energy administration in evaluating system gains from SACCPPs and in developing rational system-wide planning and retrofit projects. Finally, numerical simulation and sensitivity analysis results on the modified IEEE-39 bus system validate the robust adaptability and effectiveness of the proposed models and methods.