Investigating the potential of using coconut oil–diesel blends in a diesel engine in Rodriques Islands

Abstract

The transportation sector of Rodrigues Island is fully dependent on petroleum products, mainly diesel and to a lesser extent gasoline. As an alternative solution to reduce the consumption of petroleum product over the island, this study was thus conducted to assess the performances of coconut oil–diesel blends in a diesel engine in Rodrigues Island. The fuel properties of coconut oil blends in this study were comparable to those of diesel. The engine performance showed that the mechanical efficiency of diesel was 71 % and that of the blends were around 71–77 %. The brake specific fuel consumption (BSFC) for both diesel and blends were around 0.5 kg/kWh with engine revolution below 1,500 rpm; but above 1,500 rpm the BSFC of the blends were twice as much as that of diesel. A reduction in carbon dioxide and carbon monoxide emissions were achieved up to 16.46 and 22.81 % respectively. The land requirement for the production of coconut oil to substitute 5 and 25 % of actual diesel consumption was 0.95 and 4.73 % respectively of the total area of Rodrigues Island. The economic analysis showed that a coconut oil production plant was profitable with payback periods ranging from 4.16 years for 5 %—COCO to 1.82 years for 25 %—COCO. Potential savings on diesel importation could range from Rs. 8,630,400 to Rs. 43,152,000.