Bagasse energy cogeneration potential in the Zimbabwean sugar industry

The cogeneration of steam and electricity has become the norm in the sugarcane industry worldwide. This process has been taken further to a stage where sugar companies can export a substantial amount of energy to the grid. Mauritius and Reunion Islands have implemented state of the art technology in bagasse energy cogeneration. It is on this basis that the potential for cogeneration in Zimbabwe's sugar industry is being examined. The findings indicate that it is technically feasible to implement such a project. A full economic and financial feasibility study would still need to be done. Two plants of 105 MW each can be put in place, providing about 517 GWh of clean bagasse firm power to the Zimbabwe Electricity Supply Authority. Bagasse would be used during the crop season and coal during the off-crop season. Coal usage during the off-season, will enable the exportation of extra power to the grid. This kind of project, which can save money for the utility, meets about 8% of the country's electrical energy needs, reduces the amount of foreign currency needed to import electricity, results in improved efficiency in the sugar industry and can avoid the use of 293 750 tonnes of coal, hence avoiding the emission of 885 000 tonnes of carbon dioxide and the production of 47 000 tonnes of coal ash. The sugar millers would accrue revenue benefits equal to those revenues from selling sugar that accrue to the milling activities only. (C) 2002 Elsevier Science Ltd. All rights reserved.