Two-stage solar tunnel chili drying: Drying characteristics, performance, product quality, and carbon footprint analysis

• Solar tunnel dryer improved the drying rate by 33.3% compared to open sun drying. The effective moisture diffusivity of solar increased 34.9%. both varieties varied from 2.94 E−09 4.47E−09 m 2 s −1 . overall system efficiency was in range 24.12–31.3%. net CO mitigation 10.9 13 tons per year. An indirect two-stage has been developed study characteristics two chili pepper varieties. effect layer density on time and loss investigated. Thirteen thin layer-drying models have analyzed fit experimental data. results showed that process occurred falling period. A safe storage content 11–12% (w.b) achieved within 50–80 h. Modified Henderson Pabis Verma et al. model accurately described MF BL respectively. efficiencies collectors 66.44% 76.53%. found specific energy consumption ranged 2.1 2.44 kWh/kg emission calculated as 53.8 kg/kWh. payback period 2.36 years provide good quality attributes carbon footprint renewable energy-based technologies better benefit conventional systems maximum minimum earned credit (ECC) US dollar be 162.880 136.250 year