Development and Experiments on a Batch-Type Solar Roaster—An Innovative Decentralized System for Coffee Roasting

This research was conducted to investigate the roasting capacity of a batch-type directly solar radiated roasting system for the decentralized processing of coffee using solar energy. Experimental results revealed that the roaster was capable of roasting a batch of 2 kg coffee beans in 20, 23, and 25 minutes subjected to light roasts, medium roasts, and dark roasts, respectively. The payback period of the solar roaster unit was estimated to be 1038 working sunshine hours, making it viable for commercialization.