1. Department of Mechanical Engineering, Andalas University, 25163 Padang, Sumatera Barat, Indonesia
2. Department of Electrical Engineering, Andalas University, 25163 Padang, Sumatera Barat, Indonesia
3. Research Centre for Biomass and Bio products, National Research and Innovation Agency (BRIN), Cibinong Science Centre, West Java 16911, Indonesia