One CNG/petrol and two ethanol/petrol passenger cars were tested using the NEDC and Artemis cycles. Conventional petrol, compressed biogas (CBG), Swedish summer (E85) and winter ethanol fuels (E85W) were used. The tests were performed at 22°C and -7°C. Regulated emissions, particulate mass (PM), particle number (PN), CH4, HC speciation and aldehyde were measured.
Operating with the ethanol fuels, ethanol/petrol vehicles had lower energy consumptions comparing to petrol fuel. E85 fuel led to reductions in NOx, 1,3-butadiene, benzene, toluene and PN emissions but increases in aldehyde emissions during the 22°C NEDC tests. Both E85 and E85W led to high aldehyde, CO, HC, PM and PN emissions in the -7°C NEDC tests.
For the CNG/petrol vehicle, CBG fuel led to decreased energy consumption, NOx, PM and PN emissions but increased CH4 emissions comparing to petrol fuel.