Design and Testing of a Desiccant-Enhanced Evaporative Cooler

Nnamdi V. Ogueke; Ekene S. Mbonu; Victor A. Jumbo; Desmond O. Nwadike; Januarius C. Njoku; Damaris A. Onyebuchulam

doi:10.53941/tsa.2026.100015

Abstract

Evaporative cooling is one method that could help reduce post-harvest losses. However, its increased acceptability has been hindered by its poor performance in humid regions or during humid periods of the day or year, resulting in its inability to produce cooling during those periods. To address this challenge, an enhanced evaporative cooler for the preservation of fruits and vegetables was designed and tested. The system, an active direct evaporative cooler type, incorporated desiccant (activated carbon) and addressed the challenge of frequent desiccant saturation by using a sensor to control the regeneration process. Its major components are a desiccant wheel made of galvanised steel sheet, driven by a 12 V DC motor; a 220 V, 0.14 A-rated extractor fan; a 12 V DC, 70 W adsorbent regeneration heater-fan assembly; a humidification pad; and a water tank. Activated carbon was used as the desiccant. From the results obtained, when the system was tested during humid periods, the storage chamber temperature was maintained below the ambient value throughout the experimental periods, with an average difference of 4.14–5.13 °C. The average cooling power was 259–323 W, while the average COP was 2.95–3.67. Relative humidity within the storage chamber remained above 88% throughout the period. Thus, the designed system can produce cooling, even in a very humid region.

References

1.
Food and Agricultural Organization of the United Nations [FAO]. FAOSTAT Statistical Database. 2022. Available online: https://www.fao.org/faostat/en/#data (accessed on 26 January 2025).
2.
Kapilan, N.; Isloor, A.M.; Karinka, S. A comprehensive review on evaporative cooling systems. Results Eng. 2023, 18, 101059. https://doi.org/10.1016/j.rineng.2023.101059.
3.
Anyanwu, E.E. Design and measured performance of a porous evaporative cooler for preservation of fruits and vegetables. Energy Convers. Manag. 2004, 45, 2187–2195. https://doi.org/10.1016/j.enconman.2003.10.020.
4.
Khatun, A.; Singh, R.P.; Kumar, A. Development of a low-cost evaporative cooling storage structure for perishable commodities. Food Sci. Res. J. 2019, 10, 221–231. https://doi.org/10.15740/HAS/FSRJ/10.2/221-231.
5.
Islam, M.P.; Morimoto, T. Zero energy cool chamber for extending the shelf-life of tomato and eggplant. Jpn. Agric. Res. Q. 2012, 46, 257–267. https://doi.org/10.6090/jarq.46.257.
6.
Prabha, A.; Sharma, H.R.; Goel, A.K.; et al. Changes in Ascorbic Acid Content of Lemon Fruit Stored in Zero Energy Cool Chamber and under Ambient Atmosphere. J. Dairy. Foods Home Sci. 2006, 25, 73–75.
7.
Ronoh, E.K.; Kanali, C.L.; Ndirangu, S.N.; et al. Performance Evaluation of an Evaporative Charcoal Cooler and Its Effects on Quality of Leafy Vegetables. J. Postharvest Technol. 2018, 8, 60–69.
8.
Ronoh, E.K.; Kanali, C.L.; Ndirangu, S.N. Effectiveness of an evaporative charcoal cooler for the postharvest preservation of tomatoes and kales. Res. Agr. Eng. 2020, 66, 66–71. https://doi.org/10.17221/52/2019-RAE.
9.
Ohagwu, C.J.; Nwakaire, J.N.; Ugwu, S.N.; et al. Evaluation of Fresh and Fleshy Cucumber Quality and Shelf-Life Using Charcoal Cooler Bin in the Tropics. Agric. Eng. Int. CIGR J. 2023, 25, 285–295.
10.
Defraeye, T.; Schudel, S.; Shrivastava, C.; et al. The charcoal cooling blanket: A scalable, simple, self-supporting evaporative cooling device for preserving fresh foods. Biosyst. Eng. 2024, 238, 128–142. https://doi.org/10.1016/j.biosystemseng.2023.12.001.
11.
Güzelel, Y.E.; Olmuş, U.; Büyükalaca, O. Performance evaluation of different types of indirect evaporative coolers: A CFD-based comparative study. J. Build. Eng. 2024, 96, 110399. https://doi.org/10.1016/j.jobe.2024.110399.
12.
Muñoz, R.C.; Diuco II, L.T.; Martinez, S.M.S.; et al. Automated Electronic Evaporative Cooler for Fruits and Vegetables Preservation. Int. J. Eng. Sci. Res. Technol. 2017, 6, 352–364. https://doi.org/10.5281/zenodo.814406.
13.
Awafo, E.A.; Nketsiah, S.; Alhassan, M.; et al. Design, Construction, and Performance Evaluation of an Evaporative Cooling System for Tomatoes Storage. Agric. Eng. 2020, 24, 1–12. https://doi.org/10.1515/agriceng-2020-0031.
14.
Babaremu, K.O.; Adekanye, T.A.; Okokpujie, I.P.; et al. The Significance of Active Evaporative Cooling System in the Shelf Life Enhancement of Vegetables (Red and Green Tomatoes) for Minimizing Post-Harvest Losses. Procedia Manuf. 2019, 35, 1256–1261. https://doi.org/10.1016/j.promfg.2019.06.084.
15.
Ndukwu, M.C.; Manuwa, S.I.; Olukunle, O.J.; et al. Development of an Active Evaporative Cooling System for Short-Term Storage of Fruits and Vegetable in a Tropical Climate. Agric. Eng. Int. CIGR J. 2013, 15, 307–313.
16.
Adekanye, T.; Babaremu, K.; Okunola, A. Evaluation of an Active Evaporative Cooling Device for Storage of Fruits and Vegetables. Agric. Eng. Int. CIGR J. 2019, 21, 203–208.
17.
Mogaji, T.S.; Fapetu, O.P. Development of an Evaporative Cooling System for the Preservation of Fresh Vegetables. Afr. J. Food Sci. 2011, 5, 255–266.
18.
Zakari, M.D.; Abubakar, Y.S.; Muhammad, Y.B.; et al. Design and Construction of an Evaporative Cooling System for the Storage of Fresh Tomato. ARPN J. Eng. Appl. Sci. 2016, 11, 2340–2348.
19.
Langat, V.K.; Kanali, C.L.; Ronoh, E.K.; et al. Performance evaluation of an evaporative charcoal cooler utilizing thin-film photovoltaic system for preservation of avocado. Int. J. Agric. Environ. Res. 2022, 8, 290–302. https://doi.org/10.51193/IJAER.2022.8206.
20.
Ndukwu, M.C.; Usoh, G.; Akpan, G.; et al. Development of a Small Dual-Chamber Solar PV-Powered Evaporative Cooling System for Fruit and Vegetable Cooling with Techno-Economic Assessment. Agri. Eng. 2024, 6, 2553–2576. https://doi.org/10.3390/agriengineering6030149.
21.
Amer, O.; Boukhanouf, R.; Ibrahim, H.G. A Review of evaporative cooling technologies. Int. J. Environ. Sci. Dev. 2015, 6, 111–117. https://doi.org/10.7763/IJESD.2015.V6.571.
22.
Obura, J.M.; Banadda, N.; Wanyama, J.; et al. A Critical Review of Selected Appropriate Traditional Evaporative Cooling as Postharvest Technologies in Eastern Africa. Agric. Eng. Int. CIGR J. 2015, 17, 345–354.
23.
Mekonen, T.N.; Delele, M.A.; Molla, S.W. Development and Testing of Solar Powered Evaporative Air-Cooling System with an Improved Performance. Cogent Eng. 2023, 10, 2178115. https://doi.org/10.1080/23311916.2023.2178115.
24.
Samer, M.; Abdelsalam, E.; Abd Elhay, Y.B. Enhancing the Efficiency of Evaporative Cooling Pads for Livestock Barns and Greenhouses by Moisture Adsorption. Agric. Eng. Int. CIGR J. 2016, 17, 36–63.
25.
Lee, Y.; Park, S.; Kang, S. Performance analysis of a solid desiccant cooling system for a residential air conditioning system. Appl. Therm. Eng. 2021, 182, 116091. https://doi.org/10.1016/j.applthermaleng.2020.116091.
26.
Chen, L.; Deng, W.; Chu, Y. Experimental study on desiccant evaporative combined chilled air/chilled water air conditioning systems. Appl. Therm. Eng. 2021, 199, 117534. https://doi.org/10.1016/j.applthermaleng.2021.117534.
27.
Kashif, M.; Niaz, H.; Sultan, M.; et al. Study on Desiccant and Evaporative Cooling Systems for Livestock Thermal Comfort: Theory and Experiments. Energies 2020, 13, 2675. https://doi.org/10.3390/en13112675.
28.
Zhang, Y.; Chen, Y.; Yang, H.; et al. Experimental performance investigation on a desiccant-assisted two-stage evaporative cooling system in hot and humid areas. Appl. Energy 2025, 377, 124704. https://doi.org/10.1016/j.apenergy.2024.124704.
29.
Hussain, G.; Aleem, M.; Sultan, M.; et al. Evaluating Evaporative Cooling Assisted Solid Desiccant Dehumidification System for Agricultural Storage Application. Sustainability 2022, 14, 1479. https://doi.org/10.3390/su14031479.
30.
Raza, H.M.U.; Sultan, M.; Aleem, M.; et al. Experimental study on advanced indirect evaporative cooling and desiccant dehumidification systems for agricultural greenhouses. Int. Commun. Heat. Mass. Transf. 2026, 172, 110321. https://doi.org/10.1016/j.icheatmasstransfer.2025.110321.
31.
Mahmood, M.H.; Sultan, M.; Miyazaki, T. Solid desiccant dehumidification-based air-conditioning system for agricultural storage application: Theory and experiments. Proc. Inst. Mech. Eng. Part. A J. Power Energy 2019, 234, 534–547. https://doi.org/10.1177/0957650919869503.
32.
Hraiech, I.; Zallama, B.; Belkhiria, S.Z.G.; et al. Experimental characterization of silica gel adsorption and desorption isotherms under varying temperature and relative humidity in a fixed bed reactor. Sci. Rep. 2025, 15, 29041. https://doi.org/10.1038/s41598-025-14677-7.
33.
Chairunnisa; Miksik, F.; Miyazaki, T.; et al. Development of biomass based-activated carbon for adsorption dehumidification. Energy Rep. 2021, 7, 5871–5884. https://doi.org/10.1016/j.egyr.2021.09.003.
34.
Cimbala, J.M. Experimental Uncertainty Analysis. 2013. Available online: https://www.me.psu.edu/cimbala/me345/Lectures/Exper_Uncertainty_Analysis.pdf (accessed on 11 October 2025).
35.
Liao, C.M.; Singh, S.; Sen, T. Part A: Toxic/ Hazardous Substances and Environmental Engineering Characterizing the performance of alternative evaporative cooling pad media in thermal environmental control applications. J. Environ. Sci. Health 1998, 33, 1391–1417. https://doi.org/10.1080/10934529809376795.
36.
Delele, M.A.; Ngcobo, M.E.K.; Getahun, S.T. et al. Studying airflow and heat transfer characteristics of a horticultural produce packaging system using a 3-D CFD model. Part I: Model development and validation. Postharvest Biol. Technol, 2013, 86, 536–545. https://doi.org/10.1016/j.postharvbio.2013.08.014.
37.
Stull, R. Wet-Bulb Temperature from Relative Humidity and Air Temperature. J. Appl. Meteorol. Climatol. 2011, 50, 2267–2269. https://doi.org/10.1175/JAMC-D-11-0143.1.
38.
Eldessouky, H. Performance Analysis of Two-Stage Evaporative Coolers. Chem. Eng. J. 2004, 102, 255–266. https://doi.org/10.1016/j.cej.2004.01.036.
39.
Jain, D. Development and testing of two stage evaporative cooler. Build. Environ. 2007, 42, 2549–2554. https://doi.org/10.1016/j.buildenv.2006.07.034.
40.
Heidarinejad, G.; Bozorgmehr, M.; Delfani, S.; et al. Experimental investigation of two-stage indirect/direct evaporative cooling system in various climatic conditions. Build. Environ. 2009, 44, 2073–2079. https://doi.org/10.1016/j.buildenv.2009.02.017.
41.
Velasco-Gómez, E.; Tejero-González, A.; Jorge-Rico, J.; et al. Experimental investigation of the potential of a new fabric-based evaporative cooling pad. Sustainability 2020, 12, 7070. https://doi.org/10.3390/su12177070.
42.
Doğramaci, P.A.; Riffat, S.; Gan, G.; et al. Experimental study of the potential of eucalyptus fibres for evaporative cooling. Renew. Energy 2019, 131, 250–260. https://doi.org/10.1016/j.renene.2018.07.005.
43.
Awafo, E.; Addo, A.; Bart-Plange, A. Performance analysis of a desiccant evaporative cooling system for mango fruit storage in the savannah and transitional zones of Ghana. Agric. Eng. 2019, 23, 1–14. https://doi.org/10.1515/agriceng-2019-0021.
44.
Ogueke, N.V.; Jumbo, V.A.; Njoku, J.C.; et al. Evaporative Cooling for Agricultural Preservation: Technologies, Challenges, and Future Prospects. Therm. Sci. Appl. 2026, 1, 122–137. https://doi.org/10.53941/tsa.2026.100009.
45.
Mugwaneza, E.; Nyaanga, D.; Wafula, N. Performance evaluation of experimental solar evaporative cooling systems. J. Eng. Agric. Environ. 2024, 10, 1–10. https://doi.org/10.37017/jeae-volume10-no2.2024-2.

Scilight Press

Author Information

Abstract

Keywords

References

About Scilight

Journals

Publishing Policies

Contact Us