Page 281 - Materials Chemistry, Second Edition

272 D. Rathore et al.

Fig. 1 A generalized scheme for LCA of biofuel production

3 Comparison of Different LCA Studies of Biofuels

Bioethanol and biodiesel are the most commonly produced biofuels, and currently
these are derived mainly from food crops such as maize, soya, and sugarcane.
Biofuels derived from food crops are known as first-generation biofuels. New
technologies in advanced stages of development will allow alternative feedstocks
to be used for bioenergy production and are known as second-generation and third-
generation biofuels (IEA 2008; Maltitz et al. 2009; Nigam and Singh 2011, Singh
et al. 2011). Over 200 feedstocks have been listed for the biofuel family. Use of
biofuel over the fossil fuel requires a critical assessment for actual benefit from it.
Various LCA studies showed variable results with different energy crop and
products (Davis et al. 2009). A comparison of several LCA studies conducted by
different researchers focusing on different biofuel for different purpose is presented
in Table 1.
Huo et al. (2009) analyzed four different biofuels scenarios, produced from
soybean oil. It was identified that allocation methods for coproducts and avoided
emissions are critical to the outcome of the study. Additionally, it was also pointed