Integrating a novel pumped thermal electricity storage system with industrial applications: Simultaneous achievements in flue gas heat recovery, carbon capture, and energy storage

Pumped thermal electricity storage (PTES) has emerged as a promising medium-long-term energy storage candidate, demonstrating geographical independence through thermomechanical decoupling, along with inherent safety features and modular scalability for grid integration. However, the power-to-power conversion efficiency of current PTES systems is relatively low and constrained by low-grade heat sources. To address this issue, this paper proposes a novel industrial process-integrated Pumped Thermal Energy Storage (PTES) system. This system utilizes low-grade industrial flue gas as the PTES low-temperature heat source, simultaneously reducing flue gas temperatures to facilitate absorption-based carbon capture. A high-temperature heat pump subsequently elevates and stores thermal energy, which drives thermally driven regeneration of the absorbent solution, achieving synergistic heat-electricity utilization. Furthermore, monetization of captured carbon through trading directly reduces the levelized cost of electricity storage for the PTES system. Comprehensive performance evaluation using five key metrics—power-to-power (PTP) efficiency, exergy efficiency, heat recovery efficiency, carbon capture efficiency, and levelized cost of storage (LCOS)—analyzes system configurations and identifies the optimal solution. The results show that the power-to-power efficiency for Basic-PTES coupled with carbon capture (B-CCPTES), Regenerative-PTES coupled with carbon capture (R-CCPTES), and Preheating and Regenerative-PTES coupled with carbon capture (PR-CCPTES) are 50.24 %, 66.37 %, and 62.53 %, respectively; the exergy efficiency are 30.42 %, 37.19 %, and 35.11 %, respectively; and the LCOS values are 0.53 $/kWh, 0.47 $/kWh, and 0.51 $/kWh. Among these configurations, the R-PTES configuration demonstrates the optimal overall system performance. The maximum values of heat recovery efficiency and carbon capture efficiency are 55.25 % and 95 %, respectively.