Opportunities and challenges for bioenergy-livestock integrated systems in Brazil

Abstract Bioenergy is seen as a key option to meet future energy demands and mitigate climate impacts. However, large-scale deployment of bioenergy can cause an additional pressure over land resources and correspondent sustainability impacts. Enhanced land management practices are fundamental to intensify land-based outputs under different climate mitigation scenarios. Bioenergy-livestock integration (BLI) is a win-win strategy to climate mitigation while ensuring food and fibers demands from the society by using bioenergy by-products as animal feed to release land to additional industrial crops production. This study comparatively assesses BLI opportunities in Brazil to better understand the sustainability issues of the alternatives for integration of these value chains, highlighting the key techno-economic and environmental aspects. When compared to conventional systems, the BLI systems present positive techno-economic impacts and lower greenhouse gas emissions, reaching mitigations up to 32 % and 22 % for meat and ethanol production, respectively. The expansion of BLI systems in Brazil could meet projected biofuels future demands, using less than 20 % of the expected area for this expansion. Potential expansion areas are concentrated in Center-South region of Brazil. BLI systems can be further advanced by including other synergies, such as codigestion of sugarcane vinasse and cattle manure, integration of flex ethanol plants with biodiesel plants, maximization of biofuels by-products as animal feed, and inclusion of novel promising alternative industrial crops such as macauba, sweet sorghum, energy cane and short rotation eucalyptus coppice. However, we identify many potential barriers including the operational complexity, specific know-how, and necessity of economic incentives. This study may provide important insights for strategic and integrated polices for both agricultural and livestock sections as the proper sustainability assessment of an early stage of the deployment of enhanced BLI systems may help to meet global future demands of energy while also contributing to climate change targets.