Abstract: This paper investigates the scope of utilizing biodiesel developed from both Karanja and Palm oil as an alternative diesel fuel. The continuous increasing demand for energy and the decreasing petroleum resources has led to the search for alternative fuel which is renewable and sustainable. Vegetables oils are simplest route of biofuel utilization in direct injection compression ignition (DICI) engines however several operational and durability problems are encountered while using straight vegetable oils in CI engines due to their high viscosity and low volatility. The objective is to compare the performance and emission characteristics of Karanja and Palm oil biodiesels on direct injection (DI) diesel engine. Performance and exhaust emissions of diesel engine have been experimentally investigated with Karanja oil (K100) and its blend (K10, K20, K40, K60 and K80) with diesel fuel. Similarly the Performance and exhaust emissions of diesel engine have been experimentally investigated with palm oil (P100) and its blend (P10, P20, P40, P60 and P80) with diesel fuel. Engine performance parameters namely break thermal efficiency, specific fuel consumption (SFC) and mechanical efficiency of CO, HC, CO2 and NOx were determined for different loading conditions and at constant engine speed of 1500 rpm. From this comparative study it is found that P40 showed better performance and emissions among the tested fuels.

Keywords: Karanja oil, Palm oil, Performance, Emission and Consumption