乙醇可以帮助实现能源和环境目标
Alexander E Farrell1, Richard J Plevin, Brian T Turner
1Energy and Resources Group, University of California, Berkeley, CA 94720-3050, USA. aef@berkeley.edu
Science (New York, N.Y.)
|January 28, 2006
概括
评估燃料乙醇,这项研究发现当前的玉米乙醇比汽油油油耗少,但温室气体排放量类似. 大规模的生物燃料使用可能需要先进的纤维素技术,以获得更好的环境效应.
科学领域:
- 能源科学 能源科学
- 环境科学 环境科学
- 农业科学 农业科学
背景情况:
- 建议增加生物燃料的使用,以减轻对石油的依赖.
- 燃料乙醇,特别是来自玉米,是重要的生物燃料.
- 生物燃料生产对环境和能源的影响需要彻底评估.
研究的目的:
- 评估燃料乙醇生产对能源平衡和环境的影响.
- 批判性地审查现有的燃料乙醇分析.
- 发现当前生物燃料评估方法的局限性.
主要方法:
- 六个代表性燃料乙醇分析的评估.
- 识别先前研究中的方法缺陷 (例如,忽视副产品,使用过时的数据).
- 为特定的资源投入开发新的指标.
主要成果:
- 玉米乙醇技术的石油密集性比汽油要低.
- 玉米乙醇的温室气体排放量与汽油相当.
- 之前的负净能发现研究是有缺陷的.
结论:
- 目前的玉米乙醇生产具有环境缺陷.
- 生物燃料技术的重大进步,如纤维素乙醇,对于可持续的大规模实施是必要的.
- 对生物燃料的全面环境指标进行进一步的研究是必不可少的.
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