In the present study the desiccant air-conditioning system has been investigated for the on-farm storage of fruits and vegetables in Pakistan. In this regard, ideal storage zone for the studied agricultural products is established in order to ascertain the system applicability. The dehumidification performance of the silica-gel based desiccant wheel has been analysed with low regeneration temperature (50°C) by using the model of Beccali et. al. Three environmental conditions (A: highly humid, B: moderately humid & C: less humid) are considered for the analysis of desiccant air-conditioning system. The latent and sensible loads of air-conditioning are achieved by the silica-gel desiccant wheel dehumidification and Maisotsenko cycle evaporative cooling respectively. The results of the study envisaged that desiccant wheel performs higher dehumidification in climatic condition ‘A’ due to higher ambient air relative humidity as compared to the other climatic conditions. However, higher heat energy is required for its regeneration in the climatic condition ‘A’. This study concluded that the desiccant air-conditioning system can be efficiently used for on-farm storage of fruits and vegetables in Pakistan. Also, the renewable energy sources of the country like solar energy and bio-gas can be potentially harvested for the regeneration of desiccant wheel. The study further proposes the use of hybrid desiccant air-conditioning system where standalone DAC system cannot achieve the sensible load.
Keywords: desiccant, air-conditioning, agriculture, storage, Pakistan