This study designed a semi-automatic screw-press briquette machine to produce a high-density charcoal briquette. The machine uses a 3 kN compaction force to extrude briquettes from carbonized rice husk and coconut fiber. Results showed carbonized rice husk briquettes achieved an average bulk density of 0.9268 \({\text{gcm}}^{-3}\) , while coconut husk briquettes recorded 0.809 \({\text{gcm}}^{-3}\) due to their fibrous nature. Water boiling tests revealed that rice husk briquettes took 60 min to boil 5 L, while coconut husk briquettes reduced this to 35.6 min. Thermal efficiencies were 30.3% and 32.7%, respectively. The calorific values of the rice husk and coconut husk briquettes were 15 \({\text{MJkg}}^{-1}\) and 17 \({\text{MJkg}}^{-1}\) with burning rates of 7.82 and 10.23, respectively. The moisture content for both briquettes was 14.5% and 15%, respectively. The machine demonstrates the potential to produce briquettes with comparable density with promising cooking efficiency.
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