Energy analysis of a fruit drying plant in Adeiso, Ghana

Abstract: The purpose of the project has been to work out recommendations that reduce the energy-related costs and environmental impact of HPW Fresh & Dry Ltd., a fruit drying factory in Ghana. The factory produces electricity with diesel and biogas but also purchases electricity from the national electricity company. Heat for the drying process is produced from biogas, kerosene and solar panels. In the project the energy system was analyzed by measuring production and consumption of heat and electricity. The project results show that the factory can become self-sufficient on heat if the available energy is used more efficient. The production units for both electricity and heat have low efficiencies. Inadequate insulation and sealing contributes to the poor performance of the heat system. The electricity measurements show that several electrical loads are unbalanced and that the three phase cooling machines are not fully utilized. The factory is recommended to invest in a new kerosene boiler and a roaster boiler for combustion of coconut waste. Furthermore, the biogas should be combusted in a boiler instead of in the now used combined heat and power engine (CHP), for improved utilization of the gas. Unused capacity of the three phase cooling machines could replace the less efficient single-phase cooling machines. Moreover, the electrical loads should be balanced and the usage of motors connected to the biogas plant minimized. By insulating pipings and seal leakages, heat losses and the need of cooling will decrease. Finally, the factory is recommended to install automatic regulation of the boilers to avoid over-heating of the storage tank.