Comparative life cycle assessment of uses of rice husk for energy purposes

Purpose: Recently, the Thai government has been advancing the expanded use of biomass as an alternative source of energy substituting it for the fossil fuels that have been shown to be harmful to the environment. Rice husk, one of the main sources of biomass in Thailand, has already been used as an energy source in many different applications and has been successful in reducing the consumption of fossil fuels. At present (2011), the main use of rice husk in Thailand is as fuel to generate electricity. However, rice husk can potentially be used to produce other forms of energy such as cellulosic ethanol. This paper compares the environmental performance of the current main use of rice husk for energy purposes in the Thai context, i.e., for electricity generation with the prospective use, i.e., for cellulosic ethanol production. The results from this study will identify the more environmentally friendly option for use of rice husk for energy purposes. Materials and methods: To determine the more environmentally friendly rice husk use option, that being the option that showed the greatest reduction of environmental impacts, the environmental impacts of the two selected rice husk use options were compared with the environmental impacts of their conventional energy production processes using the life cycle assessment (LCA).