Sustainable Development of Sweet Sorghum-Based Fuel Ethanol from the Perspective of Water Resources in China

Abstract

Bioenergy is expected to play a key role in achieving a future sustainable energy system. Sweet sorghum-based fuel ethanol, one of the most promising bioenergy sources in China, has been receiving considerable attention. However, the conflict between sweet sorghum development and traditional water use has not been fully considered. The article presents an integrated method for evaluating water stress from sweet sorghum-based fuel ethanol in China. The region for developing sweet sorghum was identified from the perspective of sustainable development of water resources. First, the spatial distribution of the water demand of sweet sorghum-based fuel ethanol was generated with a Decision Support System for Agrotechnology Transfer (DSSAT) model coupled with Geo-Information System (GIS). Subsequently, the surplus of water resources at the provincial scale and precipitation at the pixel scale were considered during the growth period of sweet sorghum, and the potential conflicts between the supply and demand of water resources were analyzed at regional scale monthly. Finally, the development level of sweet sorghum-based fuel ethanol was determined. The results showed that if the pressure of water consumption of sweet sorghum on regional water resources was taken into account, about 23% of the original marginal land was not suitable for development of sweet sorghum-based fuel ethanol, mainly distributed in Beijing, Hebei, Ningxia, Shandong, Shanxi, Shaanxi, and Tianjin. In future energy planning, the water demand of energy plants must be fully considered to ensure its sustainable development.