Solar dryer dome to improve post-harvest processing for smallholder farmers: A sustainable innovation for rural agriculture

Abstract

Post-harvest losses among smallholder farmers in tropical regions remain a signi5icant challenge due to high humidity and unpredictable weather impacting traditional open-sun drying methods. This study introduces a Solar Dryer Dome (SDD) that integrates passive ventilation, solar photovoltaic energy (660 Wp), and IoT-based environmental monitoring to provide a hygienic, ef5icient, and fully off-grid drying solution. The dome's semi-spherical design enhances natural air5low, reducing humidity buildup and reliance on active fans, while its digital control system enables real-time adjustment of temperature, humidity, and air quality parameters. Field trials using sliced Beneng taro (Colocasia gigantea) leaves in East Kalimantan demonstrated a drying time reduction from 38 hours to 5.8 ± 0.4 hours, and a 90% decrease in microbial load compared to open-sun drying, with stable internal temperatures of 42-47°C and relative humidity below 60%. Economic analysis estimates a system payback of approximately three years, considering reduced labor and increased product quality. Farmer feedback highlights protection from sudden rainfall, labor savings, and higher market value. By combining passive ventilation, renewable energy, and IoT monitoring, the SDD presents a scalable, climate-resilient innovation supporting sustainable post-harvest processing and improved livelihoods in rural agricultural communities.