An IoT-Based Smart Solar Dryer Development for Coffee Bean Drying Optimization as an Applied Technology Solution

Optimalisasi Proses Pengeringan Biji Kopi Menggunakan Smart Solar Dryer Berbasis IoT sebagai Solusi Teknologi Tepat Guna

Abstract

Drying is a critical stage in coffee post-harvest processing that significantly influences the physical quality, moisture content, and overall quality of green coffee beans. Coffee farmers in the Glodogan Coffee Farmers Group, Glempang Village, Pekuncen District, Banyumas Regency, still rely on the traditional open sun drying method, which is highly dependent on weather conditions, requires a long drying period, produces uneven heat distribution, and increases the risk of contamination and non-uniform moisture content. This community service program aimed to implement an Internet of Things (IoT)-based Smart Solar Dryer as an appropriate technology to improve coffee drying practices. The implementation adopted a Participatory Technology Implementation approach consisting of four stages: partner needs assessment, prototype design and fabrication, technology implementation, and training with evaluation. The developed system integrates a greenhouse-effect drying chamber, temperature and humidity sensors, an ESP32 microcontroller, and a dashboard for real-time monitoring. The implementation demonstrated that the Smart Solar Dryer effectively supported the drying process of both coffee cherries and wet-processed green beans. The monitoring dashboard provided real-time information on drying chamber temperature, humidity, system status, and historical drying records, enabling farmers to monitor the process without opening the drying chamber. Evaluation involving six farmers indicated a Partner Satisfaction Index of 95.33%, with 76.67% of respondents strongly agreeing and 23.33% agreeing with the usefulness of the program and the implemented technology. These findings indicate that the IoT-based Smart Solar Dryer has strong potential to improve coffee post-harvest quality while encouraging the adoption of digital technologies among smallholder coffee farmers.