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Natural Resources Research, Vol. 14, No. 1, March 2005 ( C 2005)
DOI: 10.1007/s11053-005-4679-8

Ethanol Production Using Corn, Switchgrass, and Wood;
Biodiesel Production Using Soybean and Sunflower
David Pimentel1,3 and Tad W. Patzek2
Received and accepted 30 January 2005

Energy outputs from ethanol produced using corn, switchgrass, and wood biomass were each less than the respective fossil energy inputs. The same was true for producing biodiesel using soybeans and sunflower, however, the energy cost for producing soybean biodiesel was only slightly negative compared with ethanol production. Findings in terms of energy outputs compared with the energy inputs were: • Ethanol production using corn grain required 29% more fossil energy than the ethanol fuel produced. • Ethanol production using switchgrass required 50% more fossil energy than the ethanol fuel produced. • Ethanol production using wood biomass required 57% more fossil energy than the ethanol fuel produced. • Biodiesel production using soybean required 27% more fossil energy than the biodiesel fuel produced
(Note, the energy yield from soy oil per hectare is far lower than the ethanol yield from corn).
• Biodiesel production using sunflower required 118% more fossil energy than the biodiesel fuel produced.
KEY WORDS: Energy, biomass, fuel, natural resources, ethanol, biodiesel.

INTRODUCTION

unanimously approved. Numerous other investigations have confirmed these findings over the past two decades. A review of the reports that indicate that corn ethanol production provides a positive return indicates that many inputs were omitted (Pimentel, 2003).
It is disappointing that many of the inputs were omitted because this misleads U.S. policy makers and the public. Ethanol production using corn, switchgrass, and wood, and biodiesel production using soybeans and sunflower, will be investigated in this article.

The United States desperately needs a liquid fuel replacement for oil