生物谷报道：日前，美国科学家成功利用牧草作为原料生产出生物乙醇，而且生产成本低廉，出产的生物乙醇质量也比较理想。
这一研究由美国内布拉斯加大学和美国农业部研究中心的科学家历时5年合作完成，研究成果已发表在新一期的美国《国家科学院学报》上。
据参与这项研究的内布拉斯加大学教授肯·沃格尔说，科学家对内布拉斯加州、南达科他州和北达科他州一些农场种植的牧草进行了试验，结果显示，平均1公顷牧草大约能生产2800升生物乙醇，而利用同等面积的玉米大约可提取3270升的生物乙醇。
沃格尔指出，以单位面积而言，从牧草提取的生物乙醇量少于玉米，但牧草成本比玉米低很多，而且所生产的生物乙醇质量也没有太大差别，因此这项研究成果对今后开发和利用新型生物燃料具有重要意义。（中国食品产业网）
生物谷推荐原始出处：
Published online on January 7, 2008, 10.1073/pnas.0704767105
PNAS | January 15, 2008 | vol. 105 | no. 2 | 464-469
OPEN ACCESS ARTICLE
BIOLOGICAL SCIENCES / AGRICULTURAL SCIENCES
Net energy of cellulosic ethanol from switchgrass
M. R. Schmer*, K. P. Vogel*,, R. B. Mitchell*, and R. K. Perrin
*U.S. Department of Agriculture–Agricultural Research Service, University of Nebraska, 314 Biochemistry Hall, P.O. Box 830737, Lincoln, NE 68583-0737; and Agricultural Economics Department, University of Nebraska, 314A Filley Hall, Lincoln, NE 68583-0922
Edited by Pamela A. Matson, Stanford University, Stanford, CA, and approved November 21, 2007 (received for review May 21, 2007)
Perennial herbaceous plants such as switchgrass (Panicum virgatum L.) are being evaluated as cellulosic bioenergy crops. Two major concerns have been the net energy efficiency and economic feasibility of switchgrass and similar crops. All previous energy analyses have been based on data from research plots (<5 m2) and estimated inputs. We managed switchgrass as a biomass energy crop in field trials of 3–9 ha (1 ha = 10,000 m2) on marginal cropland on 10 farms across a wide precipitation and temperature gradient in the midcontinental U.S. to determine net energy and economic costs based on known farm inputs and harvested yields. In this report, we summarize the agricultural energy input costs, biomass yield, estimated ethanol output, greenhouse gas emissions, and net energy results. Annual biomass yields of established fields averaged 5.2 -11.1 Mg·ha–1 with a resulting average estimated net energy yield (NEY) of 60 GJ·ha–1·y–1. Switchgrass produced 540% more renewable than nonrenewable energy consumed. Switchgrass monocultures managed for high yield produced 93% more biomass yield and an equivalent estimated NEY than previous estimates from human-made prairies that received low agricultural inputs. Estimated average greenhouse gas (GHG) emissions from cellulosic ethanol derived from switchgrass were 94% lower than estimated GHG from gasoline. This is a baseline study that represents the genetic material and agronomic technology available for switchgrass production in 2000 and 2001, when the fields were planted. Improved genetics and agronomics may further enhance energy sustainability and biofuel yield of switchgrass.
agriculture | bioenergy | biomass | biomass energy | greenhouse gas
