A comparison of power generation and ethanol production using sugarcane bagasse from the perspective of mitigating GHG emissions

The mitigation of greenhouse gas (GHG) emissions from power generation and two ethanol production options from sugarcane bagasse were compared at grid emission factors ranging from 0.0 to 1.0 kg of carbon dioxide (CO2) equivalent per kWh. The first ethanol production method (EP 1) directly purchased electricity and steam from the grid and the factory, and the second ethanol production method (EP 2) derived the required electricity and steam from the cogeneration system using the sugarcane bagasse as boiler fuel. Data pertaining to GHG emissions from power generation were collected from published studies. A process for ethanol production from sugarcane bagasse was designed, and a simulator was developed to generate the process data using Microsoft Excel. Results show that power generation is the preferential option when the grid emission factors are higher than 0.45 kg CO2 eq/kWh. The EP 1 was advantageous in mitigating the GHG emissions when the grid emission factors were lower than 0.19 kg CO2 eq/kWh, and the EP 2 might be the most environmentally beneficial when the grid emission factors were between 0.19 and 0.45 kg CO2 eq/kWh. It is hoped that these results could be helpful in determining how to best utilize sugarcane bagasse.