|
美国一项最新研究发现，在开发生物能源过程中，以单位土地面积的能效来看，利用生物电能要比利用生物燃料更有效，前者可更好地利用土地，保护环境。 生物能源主要包括生物电能和生物燃料两大类。生物电能指的是利用各种植物秸秆进行发电，而生物燃料则是以玉米等作物和农业废弃物为原料制造的乙醇等燃料。生物能源既是可再生能源，又是无污染或低污染的绿色能源。 美国加利福尼亚大学默塞德分校等机构的研究人员对生物电能和生物燃料的对比研究发现，从土地利用角度看，生物电能要比生物燃料更有效。 研究人员在最新一期《科学》杂志上报告说，如果用同等面积土地上种植的作物来发电或制造乙醇，供应给汽车，那么使用生物电能的汽车的行驶里程要比使用乙醇的汽车多出81%。另外，前者的温室气体减排效果也要远远大于后者。 因此，研究人员认为，无论从使用效果还是从环保角度考虑，利用生物电能都比利用生物燃料更为可行。但他们表示，这项研究并没有考虑水资源消耗、生产成本等其他因素。 推荐原始出处： Science DOI: 10.1126/science.1168885 Greater Transportation Energy and GHG Offsets from Bioelectricity Than Ethanol J. E. Campbell 1*, D. B. Lobell 2, C. B. Field 3 1 College of Engineering, University of California, Merced, CA 95344, USA.; Sierra Nevada Research Institute, University of California, Merced, CA 95344, USA. 2 Program on Food Security and the Environment, Stanford University, Stanford, CA 94305, USA. 3 Department of Global Ecology, Carnegie Institution of Washington, Stanford, CA 94305, USA. The quantity of land available to grow biofuel crops without impacting food prices or greenhouse gas emissions from land conversion is limited. Therefore, bioenergy should maximize land-use efficiency when addressing transportation and climate change goals. Biomass could power either internal combustion or electric vehicles, but the relative land-use efficiency of these two energy pathways is not well quantified. Here, we show that bioelectricity outperforms ethanol across a range of feedstocks, conversion technologies, and vehicle classes. Bioelectricity produces an average 81% more transportation kilometers and 108% more emissions offsets per unit area cropland than cellulosic ethanol. These results suggest that alternative bioenergy pathways have large differences in how efficiently they use the available land to achieve transportation and climate goals. (责任编辑：Doctor001) |
