For this assessment we used official data and technical coefficients provided by a very detailed and informative study published by the Sugar Cane Agro-industry Union (UNICA) in Brazil (De Carvalho Macedo, 2005). These data have been checked against the assessment of ethanol production from sugar cane in Brazil provided by Patzek and Pimentel (2005) and [...]
There is a well-established data set for corn-ethanol production in the US, without major differences in the physical assessment of biophysical inputs and outputs among different studies. The differences found in the overall assessment of the output/input energy ratio are basically generated by different choices about how to convert the various inputs and outputs into [...]