Performance evaluation of indirect type domestic hybrid solar dryer for tomato drying: Thermal, embodied, economical and quality analysis

This study evaluated the performance of an indirect type domestic hybrid solar dryer (ITDHSD) for drying tomato flakes in terms of thermal, environmental, economical, and quality parameters. The dryer achieved a final moisture content of 9% (wb) in 10 h during November 2021. Average heat utlisation factor and coefficient of performance during experimentation for drying system were 0.67 and 0.33 respectively. Embodied energy during dryer fabrication was estimated as 1434.176 kWh. Energy payback time, total CO2 mitigation, and earned carbon credit for tomato drying in dryer were projected as 4.21 years, 12.28 Tonnes, and US$364. Initial capital cost for drying system fabrication was US$245. The drying system can pay back all initial costs in 6 months of operation as estimated for tomato flakes drying. Moreover, quality of dried tomato flakes in dryer and open sun drying was estimated and compared. Indirect type domestic hybrid solar dryer provided better quality dried tomato flakes than open sun drying method as estimated from sensory analysis, rehydration ratio, shrinkage and hardness test. Further, present system was duly compared and found superior among several existing solar drying systems in terms of drying efficiency and total CO2 mitigation. The significance of the system performance lies in its potential to provide an economical, efficient, and environmentally friendly alternative to traditional drying methods. The results demonstrate that the ITDHSD system can help reduce energy consumption, greenhouse gas emissions, and improve the quality of dried products, making it an attractive option for domestic users as well as small-scale agricultural producers. The findings of this study can provide useful insights for designing and implementing sustainable and cost-effective drying systems for other food products.