Sustainable Production of Food and Bioenergy: Techno- economic and Environmental Assessment of Sugarcane Ethanol and Livestock Integration

Abstract

Despite their advantages when replacing fossil fuels, biofuels have faced some concerns related to their expansion within the so-called “food vs. bioenergy” debate. This debate relies on the premise that the use of food crops and/or the increase of land use for bioenergy production would affect food availability and price. Nevertheless, it is worth to mention that livestock production is the largest anthropic use of land resources worldwide. In Brazil, livestock production mainly consists of extensive management with low technology level, which results in a low average productivity. The intensification of this system would release pasture areas to expand cropland for biofuels production. In this way, the integration of sugarcane ethanol and livestock production would allow taking advantage of the synergies between both systems; for instance, using sugarcane agroindustrial residues as animal feed ingredients in feedlot systems. In addition, ethanol production from lignocellulosic feedstock (second-generation process) is also a possible solution towards a productive land use, since a larger amount of biofuels can be produced per crop area. This work focuses on the sustainability assessment of a first- and second-generation (1G2G) ethanol facility that produces animal feed using sugarcane by-products integrated to livestock production in feedlots. The Virtual Sugarcane Biorefinery (VSB) – a computer framework that simulates the entire production chain and assesses the sustainability impacts of different biorefinery alternatives/routes – was used in this work. This paper indicates that the integration of a future 1G2G sugarcane mill with intensive livestock system may be a feasible alternative. Regarding the economic performance, verticalization of a mill with intensive livestock is preferable when compared to extensive cattle production. Integrated scenarios also have environmental advantages, such as the production of more outputs using the same area, as well as more efficient technologies that may represent lower emissions. In addition, this paper revealed that it is possible to sustainably produce biofuels without displacing food crops or livestock production, which otherwise could advance, for example, in forest areas.