Potential of bioenergy production from biomass wastes of rice paddies and forest sectors in Taiwan

Promoting biofuel to replace fossil fuels and alternative utilization schemes to replace conventional measures of biomass waste disposal have been considered a priority to mitigate CO2 emissions. Despite fewer land resources and higher reliance on imported energy and raw material resources, the potential for bioenergy supply in a place like Taiwan should be fully investigated. This paper presents a case study regarding the utilization of waste biomass derived from an enhanced production of rice paddy and from the forest sector in Taiwan for biofuel production. In this study, the carbon balance for the two aforementioned bioenergy production scenarios was calculated. The amount of biomass waste expected to be derived from rice husk and rice straw produced from currently planted paddy and from reactivated fallow rice paddy was estimated. Forest sector wastes consist of biomass derived from processing domestically harvested and post-consumer harvested wood products. The projection was made up to 2065. The overall annual bioenergy providing potential of the biomass, estimated by this study, to replace gasoline through bioethanol production and residual combustion and to substitute coal for power generation via combustion were approximately 222.37 PJ and 206.77 PJ, respectively. These values represent 332.56% and 323.24% of the current level of bioenergy supplies, compared to the 76.4 PJ from biomass and waste incineration in 2016. This is the first time the bioenergy potential of post-consumer harvested wood products is being identified.