Life Cycle Inventory of Electricity Cogeneration from Bagasse in the South African Sugar Industry

by Monkgogi Bonolo Otohogile

South Africa’s sugar industry is worth over $1.11 billion and South Africa is consistently ranked as one of the top 15 sugar producing countries in the world. The sugar manufacturing process also produces thousands of tonnes of a biomass called bagasse that is being underutilized. Mashoko et al. (2013) investigated the potential for the cogeneration of steam and electricity using bagasse in South Africa’s sugar industry. The authors’ developed life cycle inventories for bagasse electricity production, which they used to evaluate the environmental impacts of cogeneration. Using data supplied by various affiliated organizations and studies, Mashoko and colleagues determined the greenhouse gases, energy ratio, non-renewable energy input, sulfur dioxide, and nitrogen dioxide of a functional unit of 1 GWh of bagasse-derived electricity produced in the South African sugar industry and compared it to coal-derived electricity and bagasse-derived electricity in Mauritius. The authors found that bagasse-derived electricity performed better than coal-derived electricity in every category outlined above. Mashoko et al. argued that by increasing their boiler pressure, the sugar industry could produce cleaner electricity during the sugar life cycle by following in the footsteps of Mauritius. Bagasse-derived electricity could mitigate South Africa’s massive carbon dioxide emissions while also making the sugar industry self-sufficient and contributing to the grid. Continue reading