This study focused on Yunlin County (Taiwan), which has, in recent years, adopted environmental sustainability-oriented philosophies; hosted activities for promoting its rice straw cultural image; and discussed its practice of cultural image promotion in contrast to the environmental pollution caused by outdoor straw burning involved in such activities. However, these cultural-image-promoting activities have eliminated only part of the waste rice straw. This study thus aimed to establish an effective elimination approach through biomass-combustion-based power generation, using a coefficient calculation method to estimate the volume of biomass waste generated from major agricultural products in the county, such as rice, corns, sorghum, soybeans, peanuts, and sugarcane. The coefficient calculation method was subsequently used to estimate the volume of air pollutants emitted by agricultural biomass waste within its life cycle during the stages of transportation, grinding, and combustion in biomass power plants (equipped with waste gas treatment facilities), as a replacement of burning the waste outdoors. Finally, this study proposed recommended approaches to treating agricultural waste that facilitate pollutant reduction and sustainable environmental development.