7E + Q analysis of a novel modified mixed-mode solar dryer for porang chips

Abstract

About 68% of energy usage in the food and agriculture sector is dominated by fossil fuels. Hence, switching to renewable energy sources, such as solar energy, is imperative. For the first time, a direct-flow evacuated tube solar collector, an air recirculation system, and a paraffin thermal energy storage (TES) unit were combined in a mixed-mode solar dryer to improve its performance. This work aims to evaluate the feasibility of the new solar dryer for porang chips using the 7E + Q framework. The drying time of the proposed solar dryer varied between 17 and 21 h, which is comparable to industrial dryers. Its drying efficiency varied between 0.46 and 19.94%. The drying chamber exergy efficiency varied from 51.51 to 74.28%, where both the paraffin-TES unit and the air recirculation improved the exergy performance. The CO2 mitigation varied from 4.4 to 7.6 tonnes, while the energy payback time varied between 4.6 to 6.7 years. The payback period varied between 2.05 and 3.56 years, greatly reduced by the usage of the TES unit. The additional 3E analysis revealed that there is an increase in energy/exergy loss due to the applied modifications. Nevertheless, the proposed dryer could produce dry porang chips of good quality.