Evaluation and analysis of biogas potential from agricultural waste in Hubei Province, China

Abstract

CONTEXTBiogas, a clean and environmentally sustainable energy source, reduces agricultural waste pollution and contributes to solving the problem of rural energy shortages. Therefore, biogas development and use have increased in numerous nations, including China. OBJECTIVEThis study estimates the biogas potential of agricultural waste in Hubei Province, China. It also identifies the gap between the available biogas potential and actual total biogas production to find the cause of the low utilization rate. METHODSThe agricultural waste, including its biogas potential in Hubei Province, was estimated and analyzed using crop yields and livestock production through geographical approach. Based on that, the environmental and economic benefits of carbon emission reduction were also discussed. Then, a comparison was made between the estimated biogas potential and the actual biogas production via biogas production difference rate that could visualize the gap between them. RESULTS AND CONCLUSIONSThe results revealed that the estimated biogas potential of agricultural waste could reach 4.67 × 109 m3. This high biogas potential could lead to a carbon emission reduction effect of 2.33 × 106 tCO2. According to Clean Development Mechanism (CDM), these carbon emission savings could have an economic benefit of 2.33 × 107 USD. In addition, results also showed a significant difference between the estimated potential and actual biogas production, and the average production difference rate was 96.83%. The discrepancy between Hubei regions was also evident; areas with the lowest biogas production density per unit area accounted for only 0.5% of the highest areas. SIGNIFICANCETo sum up, this study provides a visual tool to compare theoretical biogas potential to real biogas output and offers referable optimization strategies.