The intensive increase of biofuel demand has pushed the researchers to find a sustainable biofuel production system.
LCA is the most accepted tool to assess the sustainability of biofuel production systems. The functional unit, scope, system boundary, reference system, data source, and allocation are the most important steps of an LCA study. Variations in these steps between studies affect the results significantly. Previous studies have shown that different biofuel feedstocks have different environmental burden hot spots, which refer to elevated greenhouse gas (GHG) emissions associated with a specific life cycle stage or facility process.
The present chapter is an effort to compare various LCA studies on different biofuels. The well-to-wheel (cradle-to-grave) system is recommended for the assessment of biofuels production system. An LCA study of biofuels can demonstrate their sustainability and can guide the policy makers in adopting the policies for their promotions.