Greenhouse Gas Balance for Electricity Production from Biomass Resources in Thailand

Abstract

The two major biomass resources being used for power production in Thailand are bagasse, a byproduct of sugar production, and rice husk, which remains after milling rice. Larger resources are still reportedly unused in the two agricultural sectors sugar and rice, which are the field-based commodities sugar cane trash and leaves and rice straw. An in-depth analysis was performed on the energetic use of bagasse in the sugar industry. Considering the present utilization pattern and efficiencies both in the power production and in the sugar milling process, it was found that there is still a large potential available for excess power production from bagasse in sugar mills. Rice husk has widely been used leading to local shortages in supply and increasing costs of the resource. The field residues are mainly unused for power production probably because of uncertainty in logistics and prices. For all present and possible biomass power routes LCA (Life-cycle Analysis) was conducted to establish the respective figures on energy balance and greenhouse gas (GHG) emissions. These figures were compared to the conventional power sector in Thailand to establish the net savings effect of the utilization patterns. The best results were compiled for bagasse since other resources need more fossil energy input into preparation and transport. Finally, the production costs per unit of electricity were calculated to demonstrate the viability, under the present condition in Thailand, for the power export to the national grid. The options in the rice sector lead to unfavorable economic results whereas in the sugar sector good returns are possible.