Approach of using Corn Residue as Alternative Energy Source for Power Production: A Case Study of the Northern Plain Area of Thailand

Abstract

As Thai's energy security heavily relies on imported crude oil products, the Thai government has promoted the use of alternative energy sources as a substitute for fossil fuel through the Renewable Energy Development Plan. According to this plan, 3,630 MW of electricity should be derived from biomass or agricultural residue in 2021. Although some agricultural residue has been commercially used as fuel in biomass power plants, corn residue is still leftover and has a high energy potential in some regions, e.g. in the northern part of Thailand. This study focuses on the supply chain management in using corn residue as an alternative energy source for power production in Nakorn Sawan and Petchchaboon Provinces. In 2011, almost two million tons of corn residue were generated; about 200,000 tons of which were corncob (HHV of 15-16MJ/kg) and the rest was corn trash/skin and stems (HHV of 13-15MJ/kg). Because of the uniform and compact shape of corncobs, they can be completely utilized as fuel in a conventional stoker-fired boiler for heat production. In contrast, corn trash/skin and stems are leftover in the field or burnt on the field without any energy recovery because they are bulky and non-uniform fuel, with high moisture content, which leads to difficulty in collection and transportation, as well as for thermal conversion. According to the results of this study, a processing unit is necessary to improve the properties of corn trash/skin and stems to be used as solid fuel. This processing unit can be established as a centralized plant or on the field where the residue is generated. Regarding the economic analysis, the overall cost of bio-pellet from corn trash/skin/stems is estimated to be 49.4-56.8 US$ per ton, depending on the pelletizing capacity. The bio-pellets from corn residue can easily be transported to be used as feedstock for heating or power generation by direct combustion, co-firing, or gasification technology.