Experimental performance evaluation of a solar powered evaporative cooling system for preservation of agricultural produce in tropical region

Year 2025, Volume: 11 Issue: 3, 858 - 879, 16.05.2025

Mfon O. Udo Sunday O. Oyedepo , Sunday A. Afolalu Samson O. Ongbali Oluwaseun Kilanko Richard O. Leramo Bahaa Saleh Joseph O. Dirisu James A. Omoleye Gbolahan Odewole Philip O. Babalola Samson K. Fasogbon Ejike C. Solomon Blessed Bolarinwa Odunayo Idemili O. Uchechukwu

Abstract

Lack of suitable power supplies and storage facilities are major contributors to post-harvest loss of fruits and vegetables in low- and middle-income nations. The problem of food security can be greatly alleviated by solar-powered cooling systems that store agricultural produce in a decentralized manner. In addition to decreasing food loss and waste, this approach promotes green economic growth by lowering greenhouse gas emissions. In view of this, a direct active solar-powered evaporative cooling system is developed and its performance was assessed. In this investigation, the temperature and humidity within the evaporative cooling system were recorded using a Floureon RC-4HC data logger. The data logger was configured to capture data every half an hour for six to seven hours. The wet and dry bulb temperatures of the surrounding area were recorded using a combination wet bulb and dry bulb hygrometer. To determine the relative humidity values, a psychometric chart was utilized in conjunction with the hygrometer data. To measure the air velocity entering the evaporative cooling system, a digital anemometer was employed. Readings were taken consecutively over four days with varying pad thicknesses (from 20mm to 80mm) under no load conditions and for eight days under load conditions. Results of the study shows that the temperature of the cooling chamber reduced to 25oC with a drop range from 3 to 10oC and the highest relative humidity of 88.2% was recorded inside the cooling chamber while relative humidity of 66.5% was recorded for the surroundings. The cooling efficiency of the cooling chamber was found to vary from 61.4 to 87.5% under no load conditions and 47.06 to 91.1% under load conditions. Moreover, the rate of evaporation, cooling capacity and saturation efficiency vary respectively from 0.00116 kg/s to 0.00198 kg/s; 5.284 kW to 7.736 kW and 61.40% to 87.50%. Additionally, it was observed that agricultural produce such as tomatoes, peppers, and okra stored in the evaporative cooler retained their freshness and color after 8 days, whereas those stored under room conditions lost both after 3 days. This demonstrates effectiveness of the developed solar-powered evaporative cooling system to preserve agricultural produce. Small-scale farmers in rural areas, which account for about two-thirds of all farm produce losses, the private sector, Non-Governmental Organisations and some government agencies working to promote decentralized cold-storage facilities are expected to find great value in this study.

Keywords

Ambient Temperature , Cooling Efficiency , Cooling Pad , Evaporative Cooling System , Rate of Evaporation , Relative Humidity , Solar PV

References

• [1] Chaudhari BD, Tushar RS, Patil DM, Dube A. A review on evaporative cooling technology. Int J Res Adv Technol 2015;3:88–96.
• [2] Dvizama AU. Performance evaluation of an active cooling system for the storage of fruits and vegetables [Ph.D. thesis]. Nigeria: University of Ibadan; 2000.
• [3] Amer O, Boukhanouf R, Ibrahim HG. A review of evaporative cooling technologies. Int J Environ Sci Dev 2015;6:111–117. [CrossRef]
• [4] Sukumar SR, Gopichand A, Janardhana U, Satish Kumar V, Chanti VB. Design and fabrication of water refrigeration system by creating vacuum. Int Rev Innov Res Sci Eng Technol 2015;4:2428–2433. [CrossRef]
• [5] Basediya AL, Samuel DVK, Vimala Beera V. Evaporative cooling system for storage of fruits and vegetables - a review. J Food Sci Technol 2013;50:429–442. [CrossRef]
• [6] Sajjad U, Abbas N, Hamid K, Abbas S, Hussain I, Ammar SM, et al. A review of recent advances in indirect evaporative cooling technology. Int Comm Heat Mass Transf 2021;122:105140. [CrossRef]
• [7] Kulkarni RK, Rajput SPS, Gutte SA, Patil DM. Laboratory performance of evaporative cooler using jute fiber ropes as cooling media. Int J Eng Res Appl 2014;4:60–66.
• [8] Carrasco AD, Pittard R, Kondepudi SN, Somasundaram S. Evaluation of direct evaporative roof spray cooling system. Proceedings of the Fourth Symposium on Improving Building Systems in Hot and Humid Climates, Houstan, TX, September 15-16, 1987. pp. 94–101.
• [9] Oropeza-perez I, Østergaard PA. Active and passive cooling methods for dwellings: a review. Renew Sustain Energy 2018;82:531–544. [CrossRef]
• [10] Ndukwu MC, Manuwa SI. Review of research and application of evaporative cooling in preservation of fresh agricultural produce. Int J Agric Biol Eng 2014;7:85–99.
• [11] Kapilan N, Isloor AM, Karinka S. A comprehensive review on evaporative cooling systems. Result Eng 2023;18:101059. [CrossRef]
• [12] Tiwari GN, Jain D. Modeling and optimal design of evaporative cooling system in controlled environment greenhouse. Center for Energy Studies, Indian Institute of Technology. Int J Energy Convers Manag 2003;43:2235–2250. [CrossRef]
• [13] Olosunde WA. Performance evaluation of absorbent materials in the evaporative cooling system for the storage of fruits and vegetables [MSc thesis]. Nigeria: University of Ibadan; 2006.
• [14] Manuwa SI, Simon OO. Evaluation of pads and geometrical shapes for constructing evaporative cooling system. Modern Appl Sci 2012;6:45–53. [CrossRef]
• [15] Al-Suleiman F. Evaluation of performance of local fibers in evaporative cooling. Energy Convers Manag 2002;42:2267–2273. [CrossRef]
• [16] Olosunde WA, Igbeka JC, Olurin TO. Performance evaluation of absorbent materials in evaporative cooling system for the storage of fruits and vegetables. Int J Food Eng 2009;5:1–15. [CrossRef]
• [17] Deshmukh AM, Sapali SN. Design, development and fabrication of a mist spray direct evaporative cooling system and its performance evaluation. J Therm Eng 2019;5:42–50. [CrossRef]
• [18] Shojaei MH, Mortezapour H, Jafarinaeimi K, Maharlooei MM. An estimation method for greenhouse temperature under the influence of evaporative cooling system. J Therm Eng 2021;7:918–933. [CrossRef]
• [19] Waseem Amjad W, Munir A, Akram F, Parmar A, Precoppe M, Asghar F, et al. Decentralized solar-powered cooling systems for fresh fruit and vegetables to reduce post-harvest losses in developing regions: a review. Clean Energy 2023;7:635–653. [CrossRef]
• [20] Munir A, Ashraf T, Amjad W, Ghafoor A, Rehman S, Malik AU, et al. Solar-hybrid cold energy storage system coupled with cooling pads backup: a step towards decentralized storage of perishables. Energies 2021;14:7633. [CrossRef]
• [21] Chopra S, Müller N, Dhingra D, Pillai P, Kaushik T, Kumar A, et al. Design and performance of solar-refrigerated, evaporatively-cooled structure for off-grid storage of perishables. Postharvest Biol Technol 2023;197:112212. [CrossRef]
• [22] Kilanko O, Oyedepo SO, Joseph JO, Dirisu JO, Leramo RO, Babalola PO, et al. Typical meteorological year data analysis for optimal usage of energy system at six selected locations in Nigeria. Int J Low Carbon Technol 2023;18:637–658. [CrossRef]
• [23] Adebisi OW, Igbeka JC, Olurin FO. Performance evaluation of absorbent materials in evaporative cooling system for the storage of fruits and vegetables. Int J Food Eng 2009;5:1–15. [CrossRef]
• [24] Mogaji TS, Olorunisola FP. Development of an evaporative cooling system for the preservation of fresh vegetables. Afr J Food Sci 2011;5:255–266.
• [25] Ndukwu MC. Development of a low-cost mud evaporative cooler for preservation of fruits and vegetables. Agric Eng Int CIGR J 2011;13:333–336.
• [26] Abdulrahman TM, Sohif BM, Sulaimana MY, Sopiana K, Abduljalil AA. Experimental performance of a direct evaporative cooler operating in Kuala Lumpur. Int J Therm Environ Eng 2013;6:15–20.
• [27] Hisham ED, Hisham E, Ajeel EZ. Performance analysis of two-stage evaporative coolers. Chem Eng J 2004;102:255–266. [CrossRef]
• [28] Zakari MD, Abubakar YS, Muhammad YB, Shanono NJ, Nasidi NM, Abubakar MS, 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.
• [29] Jain SK, Chavan PP, Khedekar VP. Effect of evaporative cooling on storage of vegetables. Int J Agric Eng 2013;6:403–408.
• [30] Oyedepo SO, Omoleye JA, Kilanko O, Ejike CS, Bolarinwae-Odunayo BF, Idemili U, et al. Dataset on performance of solar powered agricultural produce cooling storage system under tropical conditions. Data Brief 2019;27:104649. [CrossRef]
• [31] Ndukwu MC, Manuwa SI, Olukunle J, Oluwalana IB. 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.
• [32] Nimkarde PG, Khod RN, Sedani SR. Development and performance evaluation of evaporative cooler for storage of fruits and vegetables. J Ready Eat Food 2019;6:31–36.
• [33] Camargo JR, Ebinuma CD, Silveria JL. Experimental performance of a direct evaporative cooler operating during summer in Brazilian city. Int J Refrig 2005;28:1124–1132. [CrossRef]
• [34] Wyehead Design. Workspace Cooling. Available at: http://www.workspacecooling.co.uk/psychr.html. Accessed May 12, 2025.
• [35] Ndukwu MC, Usoh G, Akpan G, Akuwueke L, Ekop I, Etim P, et al. Development of a small dual-chamber solar PV-powered evaporative cooling system for fruit and vegetable cooling with techno-economic assessment. AgriEngineering 2024;6:2553–2576. [CrossRef]
• [36] Onwuzuruike JA, AminU MA. Experimental determination of panel generation factor for Apo area of Federal Capital Territory in Nigeria. J Sci Res Rep 2019;24:1–5. [CrossRef]
• [37] Linden D. Handbook of Batteries. New York: McGraw-Hill; 2002. pp. 3.1–3.24.
• [38] Olarewaju RO, Ogunjuyigbe ASO, Ayodele TR, Yusuff AA, Mosetlhe TC. An assessment of proposed grid integrated solar photovoltaic in different locations of Nigeria: technical and economic perspective. Cleaner Eng Technol 2021;4:100149. [CrossRef]
• [39] Hassan Z, Misaran MS, Siambun NJ. Performance of the direct evaporative cooler (DEC) operating in a hot and humid region of Sabah Malaysia. J Adv Res Fluid Mech Therm Sci 2022;93:17–27. [CrossRef]
• [40] Dhamneya AK, Rajput SPS, Singh A. Thermodynamic performance analysis of direct evaporative cooling system for increased heat and mass transfer area. Ain Shams Eng J 2018;9:2951–2960. [CrossRef]
• [41] Sachdeva A, Rajput SPS, Kothari A. Performance analysis of direct evaporative cooling in Indian summer. Int J Res Aeronaut Mech Eng 2015;3:131–141.
• [42] Dowdy JA, Karabash NS. Experimental determination of heat and mass transfer coefficient in rigid impregnated cellulose evaporative media. ASHRAE Trans 1987;93:382–395.
• [43] Khater EG. Performance of direct evaporative cooling system under Egyptian conditions. J Climatol Weather Forecasting 2014;2:1–10. [CrossRef]
• [44] Sellam SH, Moummi A, Mehdid CE, Rouag A, Benmachiche AH, Mohammed-Melhegueg A, et al. Experimental performance evaluation of date palm fibers for a direct evaporative cooler operating in hot and arid climate. Case Stud Therm Eng 2022;35:102119. [CrossRef]
• [45] Ahmadu TO, Sanusi YS, Usman F. Experimental evaluation of a modified direct evaporative cooling system combining luffa fiber—charcoal cooling pad and activated carbon dehumidifying pad. J Eng Appl Sci 2022;69:1–18. [CrossRef]
• [46] Nugroho A, Mamat R, Xiaoxia J, Bo Z, Jamlos MF, Ghazali MF. Performance enhancement and optimization of residential air conditioning system in response to the novel FAl2O3–POE nanolubricant adoption. Heliyon 2023;9:e20333. [CrossRef]
• [47] Nugroho A, Mamat R, Bo Z, Azmi WH, Alenezi R, Najafi G. An overview of vapor compression refrigeration system performance enhancement mechanism by utilizing nanolubricants. J Therm Anal Calorim 2022;147:9139–9161. [CrossRef]
• [48] Nugroho A, Mamat R, Bo Z, Azmi WH, Yusaf T, Ghazali MF, et al. A comprehensive investigation of low proportion TiO2–POE nanolubricant stability for residential air conditioning system application. In: Johari NH, Wan Hamzah WA, Ghazali MF, Setiabudi HD, Kumarasamy S, eds. Proceedings of the 2nd Energy Security and Chemical Engineering Congress. Lecture Notes in Mechanical Engineering. Singapore: Springer; 2022. pp. 147–163. [CrossRef]
• [49] Nugroho A, Mamat R, Bo Z, Azmi WH, Yusaf T, Khoerunnisa F. Experimental assessment of TiO2–POE nanolubricant stability and optimization process using one factor at a time (OFAT) based on response surface methodology. J Therm Eng 2023;9:461–477. [CrossRef]
• [50] ASHRAE. Handbook of Standards. American Society of Heating and Refrigeration and Air Conditioning; 1982.
• [51] Mogaji TS, Fapetu OP. Development of an evaporative cooling system for the preservation of fresh vegetables. Afr J Food Sci 2011;5:225–266.
• [52] Nkolisa N, Magwaza LS, Workneh TS, Chimphango A. Evaluating evaporative cooling system as an energy-free and cost-effective method for postharvest storage of tomatoes (Solanum lycopersicum L.) for smallholder farmers. Sci Hortic 2018;241:131–143. [CrossRef]
• [53] Woldemariam HW, Abera BD. Development and evaluation of low-cost evaporative cooling systems to minimise postharvest losses of tomatoes (Roma vf) around Woreta, Ethiopia. Int J Postharvest Technol Innov 2014;4:69–80. [CrossRef]
• [54] Taylor JR. An Introduction to Error Analysis. The Study of Uncertainties in Physical Measurements. Sausalito: University Science Books; 1997. pp. 343.
• [55] Argo BD, Ubaidillah U. Thin-layer drying of cassava chips in multipurpose convective tray dryer: energy and exergy analyses. J Mech Sci Technol 2020;34:435–442. [CrossRef]
• [56] Wills RBH, Lee TH, Grahams D, Mc Glasson WB, Hall EG. Post-Harvest: An Introduction to the Physiology and Handling of Fruits and Vegetables. New York: Van Nostrand Reinhold; 1989.