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A comparison of the performance of Brassica carinata oil-derived biodiesel with a commercial rapeseed oil-derived biodiesel and petroleum diesel fuel is discussed as regards engine performance and regulated and unregulated exhaust emissions. B. carinata is an oil crop that can be cultivated in coastal areas of central-southern Italy, where it is more difficult to achieve the productivity potentials of Brassica napus (by far the most common rapeseed cultivated in continental Europe). Experimental tests were carried out on a turbocharged direct injection passenger car diesel engine fueled with 100% biodiesel. The unregulated exhaust emissions were characterized by determining the SOOT and soluble organic fraction content in the particulate matter, together with analysis of the content and speciation of polycyclic aromatic hydrocarbons, some of which are potentially carcinogenic, and of carbonyl compounds (aldehydes, ketones) that act as ozone precursors. B. carinata and commercial biodiesel behaved similarly as far as engine performance and regulated and unregulated emissions were concerned. When compared with petroleum diesel fuel, the engine test bench analysis did not show any appreciable variation of output engine torque values, while there was a significant difference in specific fuel consumption data at the lowest loads for the biofuels and petroleum diesel fuel. The biofuels were observed to produce higher levels of NOx concentrations and lower levels of PM with respect to the diesel fuel. The engine heat release analysis conducted shows that there is a potential for increased thermal NOx generation when firing biodiesel with no prior modification to the injection timing. It seems that, for both the biofuels, this behavior is caused by an advanced combustion evolution, which is particularly apparent at the higher loads. When compared with petroleum diesel fuel, biodiesel emissions contain less SOOT, and a greater fraction of the particulate was soluble. The analysis and speciation of the soluble organic fraction of biodiesel particulate suggest that the carcinogenic potential of the biodiesel emissions is probably lower than that of petroleum diesel. Its better adaptivity and productivity in clay and sandy-type soils and in semiarid temperate climate and the fact that the performance of its derived biodiesel is quite similar to commercial biodiesel make B. carinata a promising oil crop that could offer the possibility of exploiting the Mediterranean marginal areas for energetic purposes.

The 1997 Kyoto International Conference Protocol committed industrialized countries to reduce their global emissions of greenhouse gases within the period 2008 2012 by at least 5% with respect to 1990. In view of this and following the European Community directives, the Italian government approved a three-year pilot project to promote the experimental employment of biodiesel.The methyl esters of vegetable oils, known as biodiesel are receiving increasing interest because of their low environmental impact and their potential as an alternative fuel for diesel engines as they would not require any significant modification of existing engines. Consequently, an experimental research program has been developed to evaluate performance and emissions of a Diesel engine fueled with a methyl ester derived from rape seed (Rapeseed Methyl Ester or RME) by changing the composition of the diesel fuel-RME mixture.This program aims to analyze the performance and emissions of a turbocharged D.I. Diesel engine fueled with a mixture of RME and diesel fuel. In particular, the experimental investigation has performed a careful analysis of heat release, which has made it possible to give more precise information about the combustion process

The automobile market is, nowadays, characterized by a growing demand for cars equipped with diesel engines. This is because these offer smaller fuel consumption and better engine performance. A modern common rail turbocharged diesel engine provides performance equal to a gasoline engine, with same displacement, not turbo-charged but with a higher torque at lower engine speeds and with smaller fuel consumption. The methyl esters of vegetable oils, known as biodiesel, are receiving increasing interest because of their low environmental impact and their potential as an alternative fuel for diesel engines as they would not require any significant modification of existing engines. The modern common rail (CR) diesel engines are normally optimized for commercial diesel fuel. Consequently, the Electronic Control Unit (ECU) calibrations are defined to offer the best compromise between performance and emissions. If the engine is fuelled with an alternative fuel with different characteristics (net heating value, stoichiometric air fuel ratio (a/f), density, viscosity, etc.), it is clear that the calibration must be modified. In past experiments the authors have demonstrated that it is possible to optimize emissions and performances of a light duty CR diesel engine fueled with a vegetable derived fuel (rapeseed methyl ester) pure or blended with commercial diesel fuel, changing ECU parameters. This paper will show a detailed analysis of combustion in a modern diesel engine fueled with biodiesel and in particular some of the influences on engine parameters will be analyzed in order to demonstrate how an optimization strategy of ECU parameters could be applied to a diesel engine, when it is fueled with different fuels, with different physical/chemical characteristics.