Thermodynamic Performance Optimization of Adiabatic Compressed Air Energy Storage Systems Through Multi-Parameter Coupling Analysis

In response to grid peak-shaving requirements under renewable energy integration, this study investigates the thermodynamic performance of a 300 MW adiabatic compressed air energy storage (A-CAES) system, with a focus on optimizing electro-thermal efficiency through parametric analysis. A detailed thermodynamic model was developed to systematically evaluate the effects of compression/expansion stage configurations (2–4 stages), pressure ratios (4–6), and inter-stage outlet temperatures (120–190 °C) on system performance. The results demonstrate that variable-pressure operation improves round-trip efficiency by a 1.8% per unit compression ratio increase, while optimized inter-stage cooling (150 °C) reduces exergy destruction by 22.5%. Thermal efficiency monotonically improves with additional expansion stages, whereas electrical efficiency peaks at three stages (70%) before declining due to parasitic losses. Exergy analysis reveals that compressors and turbines account for 65% of total destruction, emphasizing the need for enhanced heat exchanger design. These findings provide actionable insights for balancing efficiency gains with operational constraints in large-scale A-CAES deployment.