Hybrid absorption–compression versus absorption refrigeration cycle: a thermo-economic approach-based assessment

Conventional absorption cooling systems, while environmentally beneficial through the recovery of low-grade industrial waste heat, face inherent limitations particularly their dependence on stable high-temperature thermal sources and their narrow operational range. These constraints significantly restrict their applicability, especially under fluctuating or insufficient thermal input, leading to decreased reliability and economic inefficiency. To overcome these drawbacks, this study investigates a novel hybrid refrigeration configuration that couples mechanical compression with a single-effect LiBr/H2O absorption cycle. A compressor is introduced between the evaporator and the absorber, enabling the system to operate efficiently at lower generator temperatures while enhancing thermal adaptability. A numerical simulation approach is developed and validated to evaluate the thermal and economic performance of the system under varying operating conditions, particularly within a generator temperature range of 50–110 °C. The simulation results demonstrate that the hybrid configuration improves the coefficient of performance by more than 10%, while maintaining stable and continuous operation even below 70 °C, a threshold at which conventional absorption systems typically fail. Beyond the thermal performance, this work places a strong emphasis on thermo-economic evaluation, which remains largely underexplored in such hybrid configurations. Using the levelized cost of refrigeration as a key economic indicator, the study quantifies the economic viability of the proposed system under realistic boundary conditions. The results show a refrigeration cost reduction of up to 3.27% compared to traditional absorption setups, with enhanced cost-effectiveness at lower driving temperatures and under favorable electricity pricing conditions (e.g., below $0.16/kWh). This dual thermal and economic optimization demonstrates the hybrid system’s potential as a technically robust and economically viable alternative to conventional absorption machines. The findings provide new insights into the integration of hybrid cycles for low-grade heat utilization and open up promising perspectives for real-world implementation in industrial waste heat recovery, solar-assisted cooling, and decentralized refrigeration applications.