A solar hybrid continuous dryer (SHCD) was developed to overcome the limitations of conventional solar batch drying systems for paddy. This study investigates the thermal effects on drying performance, drying kinetics, and quality characteristics of paddy at different drying air temperatures. Drying experiments were conducted at average air temperatures of 49.7 °C (Exp 1), 60.0 °C (Exp 2), and 69.6 °C (Exp 3). The results indicate that the SHCD at an air temperature drying of 60.0 °C provides the optimal balance between drying performance, energy efficiency, and product quality. At this temperature, the drying time was significantly reduced, accompanied by higher thermal efficiency and superior rice quality compared to other conditions. In contrast, drying at 49.7 °C resulted in prolonged drying time, whereas drying at 69.6 °C led to reduced thermal efficiency and deterioration in product quality. Moreover, the SHCD at 60.0 °C reduced the paddy mass from 420 kg (16.80% wet basis) to 407.63 kg (14.17% wet basis) within 165.4 min. The average drying rate, specific moisture extraction rate (SMER), and specific energy consumption (SEC) were 2.849 kg/h, 0.125 kg/kWh, and 15.649 kWh/kg, respectively, with a maximum thermal efficiency of 17.14%. Quality analysis showed that the percentages of head rice, broken rice, and rice groats were 85.60 ± 0.65%, 8.73 ± 1.98%, and 4.92 ± 1.67%, respectively. Furthermore, the drying kinetics analysis revealed that the moisture ratio (MR) data were best described by the Page model, indicating its suitability for predicting paddy drying behavior in the SHCD system. These findings present that temperature optimization plays a critical role in enhancing drying efficiency and maintaining product quality in continuous solar drying systems.
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