An economic analysis of sweet sorghum cultivation for ethanol production in North China

Sweet sorghum [Sorghum bicolor (L.) Moench] is a promising non-food energy crop. The objective of this study was to determine the economic costs and input sensitivity of sweet sorghum compared to cotton, maize, and sunflower, at two saline-alkali sites in Shandong (Wudi County) and Inner Mongolia (Wuyuan County) provinces of China. The data were collected quantitatively based on a face-to-face interview with 100 and 67 sweet sorghum growers at the two sites, respectively. The sweet sorghum grown at Wudi had lower external input (5469 CNYha(-1)), higher net return (7305 CNYha(-1)) and benefit-cost ratio (2.36) than its reference crop, cotton (18454 CNYha(-1); 3615 CNYha(-1); 1.24). At Wuyuan, the sweet sorghum showed contrasting economic performance (19541 CNYha(-1); -3438 CNYha(-1); 0.91), which was largely because of the higher labor costs compared to sunflower (10896 CNYha(-1); 15133 CNYha(-1); 2.49); and maize (9108 CNYha(-1); 14760 CNYha(-1); 2.76). The productivity of sweet sorghum per unit of external input costs (kg CNY-1) was 13.12 for Wudi and only 3.26 for Wuyuan. Based on the Cobb-Douglas production function, the external inputs of diesel and seed had a significantly positive impact on the profitability of sweet sorghum at Wudi but not at Wuyuan. However, the costs of irrigation and film cover were significantly negative. The energy crop, sweet sorghum, showed a better return to scale on investment than cotton and sunflower.