Work

Comparative parametric analysis of solar adsorption cooling systems driven by evacuated tube and parabolic trough concentrators in hot arid climates

Year: 2026

Type: article

Abstract: The growing global energy demand, especially for air conditioning in hot, dry climates such as the Middle East, necessitates clean technology alternatives to conventional vapor compression systems. This article presents a comprehensive parametric study comparing solar adsorption cooling systems comparing Evacuated Tube Collectors (ETCs) and Parabolic Trough Concentrators (PTCs) in a hot arid climate. Transient simulations for four peak days in July in Baghdad, Iraq, utilized a 9 kW silica gel/water chiller model in TRNSYS 18. Results indicate the PTC consistently achieved higher outlet temperatures (107.93 °C vs. 91.3 °C) and energy acquisition rates (peak 32.17 kW vs. 24.82 kW) than the ETC model. Increasing collector area was linearly proportional to higher Coefficient of Performance (COP) and operating hours. A 55 m² PTC system, for instance, maintained continuous COP of 0.70–0.75, while a 55 m² ETC achieved COP as high as 0.83. Although higher storage tank capacities reduced overall operating hours, PTC-driven chillers consistently had longer operated hours across tested tank capacities compared to ETCs. The techno-economic analysis shows that the ETC system enjoys both a lower levelized cost of cooling at 0.096 $/kWh and a significantly reduced simple payback period of 6.6 years compared with the PTC system, which scored 0.099 $/kWh and 12.9 years, respectively, hence giving it a clear economic advantage under the analyzed conditions.

Source: Scientific Reports

DOI: 10.1038/s41598-025-33313-y