Most of the mill engineers, in particular the mechanical engineers, may be quite familiar with the engineering thermodynamics associated with the biomass fired boilers that they operate daily in a palm oil mill. The heat content in the biomass fuel expressed usually as the calorific value is transferred to the water in a boiler to generate the steam which in turn operates the steam turbine wheels when undergoing an approximate isentropic expansion. As the alternator is coupled to the turbine shaft through a gear box, it can generate electricity that is sufficient to operate all the mill machinery as well as the domestic supplies if worker’s quarters is located nearby.