The purpose of this study was to designed and fabricated a 10 kg capacity forced convection solar dryer integrated with thermal energy storage materials, TSMA and TSMB, using locally sourced and low-cost materials for drying agricultural products. The dryer consists mainly of a well-insulated solar collector, drying chamber and photovoltaic components. The maximum collector and drying chamber temperatures obtained from three experiments at no-load conditions with two different thermal and without thermal energy storage materials were 86.2, 91.3 and 80.3 oC; and 67.8, 70.8 and 54 oC respectively, at the corresponding maximum solar radiations of 716.5, 810 and 724.7 W/m2. The recorded minimum drying chamber relative humidity of the solar dryer with TSMA, TSMB and without was 27, 24 and 23% respectively, and the corresponding ambient humidity was 70.8, 56.8 and 56.2%. A full load drying process using cocoa beans with TSMA took two full days, 10 hrs (58 hrs) to reduce initial moisture content of cocoa beans from 0.6 to 0.034 g water/g w.b. The maximum drying temperature and thermal efficiency obtained were 54 oC and 48.8% respectively. The dryer was thus viable for drying products within short time with little temperature control mechanism
drying, Solar dryer, Forced convection, Cocoa beans, Heat storage materials
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