Air‑cooled vapor‑compression chillers are increasingly deployed because they are compact and easy to install, yet their efficiency lags behind water‑cooled machines of comparable size. This study evaluates whether adiabatic pre‑cooling of condenser‑inlet air can offset that handicap while simultaneously curbing electricity use and the virtual water embodied in power generation. A first‑principles thermodynamic model was formulated for a 1,403 kW (400 RT) Carrier 30XA‑1352 chiller and validated against catalogue data. Hourly weather files for Mashhad, Tabriz, and Yazd drove year‑long simulations. Pre‑cooling lowered condenser air temperature, thereby boosting the annual coefficient of performance (COP) by 41 %, 36 %, and 47 % in Mashhad, Tabriz, and Yazd, respectively. Corresponding electricity savings reached 29 %, 26 %, and 32 %. Although the evaporative system consumed 5.9–11.1 × 10³ m³ of water per year, the reduction in power demand trimmed virtual water withdrawals at power plants by 1.1–3.2 × 10³ m³. Benefits were most pronounced in Yazd’s hot–dry climate, highlighting the climate sensitivity of adiabatic pre‑cooling effectiveness and offering a scalable, cost‑effective retrofit option.
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Saeedi,A and Rokhsat,J . (2025). Evaluation of Power Consumption and Virtual Water Use of Air-Cooled Chillers with Adiabatic Pre-Cooling in Three Representative Iranian Climates. Science and Technology in Mechanical Engineering, 4(1), 147-164. doi: 10.22034/stme.2025.523299.1129
MLA
Saeedi,A , and Rokhsat,J . "Evaluation of Power Consumption and Virtual Water Use of Air-Cooled Chillers with Adiabatic Pre-Cooling in Three Representative Iranian Climates", Science and Technology in Mechanical Engineering, 4, 1, 2025, 147-164. doi: 10.22034/stme.2025.523299.1129
HARVARD
Saeedi A, Rokhsat J. (2025). 'Evaluation of Power Consumption and Virtual Water Use of Air-Cooled Chillers with Adiabatic Pre-Cooling in Three Representative Iranian Climates', Science and Technology in Mechanical Engineering, 4(1), pp. 147-164. doi: 10.22034/stme.2025.523299.1129
CHICAGO
A Saeedi and J Rokhsat, "Evaluation of Power Consumption and Virtual Water Use of Air-Cooled Chillers with Adiabatic Pre-Cooling in Three Representative Iranian Climates," Science and Technology in Mechanical Engineering, 4 1 (2025): 147-164, doi: 10.22034/stme.2025.523299.1129
VANCOUVER
Saeedi A, Rokhsat J. Evaluation of Power Consumption and Virtual Water Use of Air-Cooled Chillers with Adiabatic Pre-Cooling in Three Representative Iranian Climates. STME. 2025;4(1):147-164 (In Persian). doi: 10.22034/stme.2025.523299.1129
Science and Technology in Mechanical Engineering