Allam cycle-based integrated energy storage system for cross-sector decarbonization

To combat climate change and reduce CO 2 emissions, carbon capture, utilization, and storage (CCUS) has emerged as an effective solution, alongside the utilization of renewable energy sources. However, these technologies encounter several obstacles, including the energy penalties associated with carbon capture and the intermittency of renewables, which complicate the electrical grid's stability. This study proposes an innovative integration of an Allam cycle, coordinated energy storage, and a polygeneration system that effectively combines renewables with CCUS, thereby enhancing sustainability and cost-effectiveness over existing energy storage alternatives. The system achieves an exergy round trip efficiency of 47.7 % and a levelized cost of storage of $47.6/MWh, outperforming conventional Power-to-X systems. A comprehensive component sensitivity analysis reveals that the electrolyzer significantly affects cost and efficiency. Enhancing its performance could substantially improve the system's overall effectiveness and economic viability, thereby supporting the transition to cleaner energy sources. • Novel storage system combines PtG and Allam cycle, achieving 47.7 % round-trip efficiency. • Electrolyzer costs dominate at 87 % of the investment, highlighting key areas for improvement. • Innovative system to bridge the gap from fossil fuels to renewable energy infrastructure. • Allam cycle and Power-to-X integrate to solve renewable intermittency issues. • The multi-source approach boosts energy security while improving resource efficiency.