Fuel is vital in palm oil industries to produce steam for electric power generating and heating purposes. Biomass and biogas have been widely utilized in palm oil mills as fuel for renewable energy whereas downstream industries still heavily depend on the fossil fuel as the boiler fuel. Complete combustion is hardly achievable even with excess of air which also causes drop in gross thermal efficiency. The phenomenon of combustion shows that volatile fuel such as methane captured from anaerobic pond is more flammable than solid fuel such as press fibre and shell.