Rising oil demand in (the) People's Republic of China has resulted in surging oil imports and mounting environmental pollution. It is projected that by 2030 the demand for fossil fuel oil will be 250 million tons. Ethanol seems to be an attractive renewable alternative to fossil fuel. This study assesses (the) PRC's ethanol supply potential by examining potential non-food crops as feedstock; emerging conversion technologies: and cost competitiveness. Results of this study show that sweet sorghum among all the non-food feedstocks has the greatest potential. It grows well on the available marginal lands and the Advanced Solid State Fermentation (ASSF) technology when commercialized will shorten the fermentation time which will lower the costs. Other emerging technologies such as improved saccharification and fermentation; and cellulosic technologies will make (the) PRC more competitive in ethanol production in the future. Based on the estimated available marginal lands for energy crop production and conversion yields of the potential feedstocks, the most likely and optimistic production levels are 19 and 50 million tons of ethanol by 2020. In order to achieve those levels, the roadmap for (the) PRC is to: select the non-food feedstock most suitable to grow on the available marginal land; provide funding to support the high priority conversion technologies identified by the scientists;, provide monetary incentives to new and poor farmers to grow the feedstocks to revitalize rural economy; less market regulation and gradual reduction of subsidies to producers for industry efficiency; and educate consumers on the impact of fossil fuel on the environment to reduce consumption. Since the share of ethanol in the overall fuel demand is small, the impact of ethanol on lowering pollution and enhancing fuel security will be minimal. (C) 2009 Elsevier Ltd. All rights reserved.