Energy Performance study of a Cooling supply system with an Lithium bromide absorption chillers using Geothermal heat

Objective. The aim of the study is to determine the boundary conditions for the efficient operation of a lithium bromide absorption refrigeration machine operating on geothermal water.
Method. The study is based on thermodynamic analysis methods.
Result. A mathematical model based on mass and energy conservation laws for the generator, condenser, evaporator, absorber, and solution heat exchanger is developed. The simulation covers geothermal water inlet temperatures from 70 to 110°C, with constant cooling water and chilled water parameters. The study investigates the impact of the heat source temperature on the generator load, cooling capacity, and the coefficient of performance (COP). The results indicate that raising the driving temperature from 70 to 110°C improves the COP from 0.52 to 0.81. A sharp decline in performance is observed below 75°C due to poor vapor generation conditions. Optimal flow rate ratios between the geothermal fluid and the chilled water are identified to maximize cooling output. Incorporating a solution heat exchanger enhances the COP by 40-45% compared to a basic cycle.
Conclusion. The findings provide practical guidance for designing efficient geothermal cooling systems and selecting appropriate operational strategies.

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