Use of Alternative Fuels in Road Transport and its Environmental Effects. A Literature Review

Abstract

This paper presents a literature review on use of alternative fuels in road transport, in respect of their performance and emission in diesel engines/vehicles. The major limitations of vegetable oils as fuel in diesel engines are their high viscosity and poor volatility, which lead to severe engine deposits, injector coking, and piston ring sticking. Transesterification reaction reduces the viscosity of vegetable oils, and the result of this reaction is biodiesel. In general, engine power dropped due to the lower heating value of biodiesel. A proper injection timing, by advancing the start of fuel injection by 1-2°BTDC, determined that all changes in engine emission are according to chemical and physical properties of the tested fuels.