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This article is a comparison of the date fruits drying performance of two most simple and common type of solar dryers. A simple even span type forced convection greenhouse dryer (FCGHD) and a forced convection cabinet solar dryer (FCCSD) were developed and tested under the climate of Hisar, India. The average values of convective heat transfer coefficients (HTC) were calculated as 0.46 and 0.53 W m−2 °C−1 for FCGHD and FCCSD, respectively. The respective average evaporative HTC was evaluated as 64.58 and 276.06 W m−2 °C−1. The drying efficiency and specific energy consumption for date fruits drying under FCCSD were, respectively, 55.2% higher and 37.87% lower than that of FCGHD. Amongst seven considered thin layer drying models, Midilli–Kucuk model showed the highest commensuration to the experimentally evaluated drying data of moisture ratio for date fruits. Higher values of effective moisture diffusivity and lower values of activation energy were observed under FCCSD. The economic prospective of both the drying arrangements has also been presented. [ABSTRACT FROM AUTHOR]

• Bifacial PVT Greenhouse dryer with PCM is designed and developed. • The operating hours and performance of the dryer with PCM are improved. • North wall insulation with aluminium foil is used for better performance. • MOGA-ANN methods have been used to explore the performance of PVT dryer. A greenhouse dryer is the most economical and environmentally friendly device used to dry various products like fruits, vegetables and meats. The operating hours and heat losses from the north wall are the main concerns for its performance. To minimize the heat losses and improve the operating hours, the present study is undertaken on a modified hybrid greenhouse dryer with a thermal energy storage system and a bifacial photovoltaic thermal for electrical (BIFPVT) and thermal energy. A thermocol was wrapped in an aluminium foil (As a reflector) and placed on the north wall to minimize energy losses. The integration of PCM made the system sustainable to use while off sunshine hours as it stores the thermal energy during daytime. It was observed that the BIFPVT system provided electrical power ranging from 2.0 to 85.5 W and 0.6–81 W with respect to solar radiation intensity on the front (I F) and rear (I R) side of BIFPVT which varied from 34–950 W/m2 and 13–350 W/m2, respectively. The drying room temperature was found to be 16–44% higher than the ambient temperature for both days. Further, the experiment result was trained using an artificial neural network and optimized with the help of multi-objective genetic algorithm tools. [ABSTRACT FROM AUTHOR]