Alternative fuels with heavy-duty engines and vehicles: VTT's contribution

The report at hand is documentation of the results from VTT on emissions and performance of heavy-duty engines and vehicles using hydrotreated vegetable oil, ester-type biodiesel, GTL diesel, CNG and selected blends in reference to fossil diesel fuel. Report combines result form three different projects which are closely related to each other. Three engines and five city buses were used for the study. In addition, the efficiency of diesel oxidation catalyst combined to particle oxidation catalyst (POCr) was measured with two engines and a long term test was performed with diesel oxidation catalyst using EN590 and RME fuels. Extensive exhaust gas emission measurements were carried out over the measurement periods. In addition to regulated emissions (HC, CO, NO, PM) a number of unregulated emission compounds were measured and analyzed e.g. CO2, aldehydes, particle size distribution and total number, polyaromatic hydrocarbons, mutagenicity of particles and several gaseous compounds with FTIR. Results show that in most cases all regulated emissions decrease with HVO, GTL and RME fuels compared to conventional EN590 diesel fuel. Alternative fuels have also a positive effect on emissions, which are considered harmful to human health. The selected results of the whole study are presented in this paper.