Sugarcane straw availability, quality, recovery and energy use: A literature review

Sugarcane straw represents, under Brazilian conditions, approximately one third of the total primary energy of sugarcane in the field. Today, its use for energy is incipient and it is mostly wasted by either burning in the pre-harvest or left on the ground to decay. Besides its potential use as feedstock for energy production, there are several possible agronomic benefits of the straw blanket left on the ground such as soil protection against erosion, increase of soil organic carbon content, inhibition of weed growth, nutrient recycling and reduction of soil water losses, to name a few. The balance of the impacts and the economic and energetic value of the straw indicate that the amount of the straw left on the ground that could be considered optimal is dependent on the local conditions, agricultural practices, characteristics of the straw and intended final use. This work is meant to shed some light into this subject to help the understanding of the importance of the various impacts of the straw blanket on the ground, the availability and quality of the straw, the economics of straw recovery and use and the main criteria for determining the amount of straw that can be recovered for bioenergy or biofuels production.