Energy Efficiency and Environmental Impact in a Sustainable Framework for Sugarcane Bioethanol Production

Abstract

Introduction: Growing concerns about climate change and dependence on fossil fuels have led to the search for sustainable energy alternatives. In this context, bioethanol produced from sugarcane is presented as a viable option, not only due to its ability to reduce greenhouse gas (GHG) emissions, also because of its contribution to energy diversification and economic development. However, for its production to be truly sustainable, it is crucial to assess the associated environmental impacts and explore optimization strategies based on the circular economy and resource efficiency.
Life Cycle Assessment (LCA) has become a key tool for measuring the sustainability of production processes. This study applies LCA to evaluate bioethanol production in Colombia, identifying its main environmental impacts and suggesting improvements that can increase its international competitiveness.
Objective: To evaluate the environmental sustainability and energy efficiency of sugarcane bioethanol in Colombia by applying Life Cycle Assessment (LCA) to quantify GHG emissions, analyze natural resource use, and propose optimization strategies aligned with international sustainability standards.
Methods: This study was based on the Life Cycle Assessment (LCA) methodology in accordance with the guidelines of ISO 14040. SimaPro software was used to model the system and assess the environmental impacts associated with bioethanol production from sugarcane. The functional unit chosen was 1 MJ of energy in the form of bioethanol, which facilitated comparisons with conventional fuels.
Primary and secondary data were collected on inputs, production processes, and emissions, taking into account variables such as climate change, water footprint, energy efficiency, and land use. The results were also compared with international benchmarks for fossil fuels and biofuels derived from other raw materials.
Results: The study's findings revealed that the agricultural phase is the main source of GHG emissions, attributable to the use of nitrogen fertilizers and crop mechanization. However, the application of precision fertilization and logistics optimization reduced the environmental burden by 40%. Furthermore, in the industrial phase, cogeneration with sugarcane bagasse contributed to a 35% decrease in external energy demand. Regarding energy efficiency, Colombian bioethanol obtained an EROI of 3.8, higher than corn biofuels produced in North America (EROI of 1.6). Additionally, water consumption per liter of bioethanol was 1.3 m³, significantly lower than the average of 2.5 m³ recorded in other producing regions in Latin America. Likewise, Colombian bioethanol allowed for a 55% reduction in CO₂ equivalent emissions, complying with environmental regulations established in the EU Renewable Energy Directive (RED II) and the US Renewable Fuel Standards (RFS). Finally, the valorization of agro-industrial waste allowed for improved sustainability of the production process through the incorporation of circular economy strategies, which optimized system efficiency and strengthened bioethanol's competitiveness in international markets.
Conclusions: Bioethanol produced from sugarcane in Colombia shows a favorable environmental impact, highlighted by the significant reduction in greenhouse gas emissions and lower water use compared to other bioenergy sources. However, there are still areas that can be improved, especially in the efficiency of fertilizer use and the optimization of the distillation process, in order to reduce additional environmental impacts. This study offers crucial evidence for the development of public policies and sustainability strategies in the bioenergy sector, positioning Colombia as an important player in the transition towards a low-carbon economy. The adoption of circular economy principles and the implementation of optimization technologies are key elements to increase the competitiveness of bioethanol in the global market and ensure its long-term sustainability.