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Sugarcane ethanol has been produced in Brazil since the early 20th century, but production increased in the mid‐1970s aiming at substituting 20% of the gasoline. Despite an increase in the 2000s production has been stable since 2008. This paper presents a review of the main developments achieved and future challenges. The sector has had positive economic and environmental results through technological development, as a result of research and development by private companies and strong public support. Sugarcane yield has steadily increased and positively impacted production costs, primarily due to better agronomic practices and breeding programs. Owing to environmental and economic reasons, there are on‐going programs to phase out burning, with the gradual replacement of manual harvest with burning by unburnt mechanised harvest. Important agronomic impacts are expected, caused by the large amount of straw left on the soil surface, which also represents a significant bioenergy potential. The sugarcane industry in Brazil has taken advantage of the combined production of sugar and ethanol, and, recently, many mills have enlarged their revenues with surplus electricity. The current efforts for diversification aim at ethanol production through hydrolysis of sugarcane residues and the development of chemical routes. From an environmental point of view, impacts related to land use change are expected on greenhouse emissions, water resources, and biodiversity. Ethanol production is likely to expand in Brazil due to the potential size of the domestic market and to the opportunities for exporting, but this will occur in a context of different and new challenges. WIREs Energy Environ 2014, 3:70–92. doi: 10.1002/wene.87 This article is categorized under: Bioenergy > Economics and Policy Bioenergy > Systems and Infrastructure Bioenergy > Climate and Environment

Mechanized sugarcane (Saccharum spp.) harvest without burning has been increasingly adopted in Brazil, increasing trash availability on the fi eld. This study aims at showing the importance of using an integrated framework tool to assess technical and economic impacts of integral harvesting and baling trash recovery strategies and different recovery rates as well as its implications in the sugarcane production, transport and processing stages. Trash recovery using baling system presents higher costs per unit of mass of recovered trash in comparison to system in which trash is harvested and transported with sugarcane stalks (integral harvesting system). However, the integrated agricultural and industrial assessment showed that recovering trash using baling system presents better economic results (higher internal rate of return and lower ethanol production cost) than the integral harvesting system for trash recovery rates higher than 30 %. Varying trash recovery fraction, stalks productivity and mean transport distance for both integral harvesting and baling systems, sensitivity analyses showed that higher trash recovery fractions associated with higher stalks yields and long transport distances favors baling system, mainly due to the reduction of bulk load density for integral harvesting system under those conditions.