Bioenergy potential from crop residues in China: Availability and distribution

The accurate estimate of the availability of crop residue resources is very important for the development of bioenergy in China, a large agricultural nation. Previous efforts to evaluate the bioenergy potential from converting straws to energy were mainly based on agricultural statistical data on the provincial/county level. Straw yield calculations generated by most of those works significantly overstate the amount of crop straws for ignoring environmental requirement and harvest constrain. The paper presents a GIS-based approach for the assessment of the availability and distribution of crop residues in China, taking into account a number of conservation issues: resources (total amount, spatial and temporal distribution), economy (transportation costs), environment, and technology. All data are converted into unified geographic unit (100 m × 100 m pixels), and integrated analysis is implemented with GIS software. The results indicate that considering conservation requirements, the production of net available crop residues is about 505.5 million tons per year. The bioenergy potential is about 253.7 million tons standard coal per year (7.4 EJ/year), which account for 8.27% of total energy consumption of the country in 2009. The results and dataset will present significant support for energy planning both at national and regional scale.