Experimental performance of direct forced convection household solar dryer for drying banana

In this study, the performance of direct forced convection household solar dryer for drying banana is presented. A solar dryer with a polycarbonate plates cover on a flat plate collector was constructed and it was designed in the parabolic shape. A polycarbonate cover is used to reduce heat losses while allowing the incident solar radiation to transmit into the dryer. Five batches of banana were dried in this solar dryer during January–July 2019. For each batch, 10 kg of bananas were dried. The results shown that the temperature of the drying air in the dryer varied between 35 °C to 60 °C from 8:00 a.m. to 6:00 p.m. The moisture content of the banana in the dryer was reduced from an initial value 72% (wet basis, wb) to a final value of 28% (wb) within 4 days, whereas the moisture content of the sun dried samples was reduced to 40% (wb) in the same period. There was a considerable reduction in drying time in the solar dryer as compared to natural sun drying with 48% saving drying time. High quality of solar dried product in terms of flavor, colour and texture were obtained. The payback period of the dryer is approximately 1.1 years.