Particle Number Emissions of Gasoline, Compressed Natural Gas (CNG) and Liquefied Petroleum Gas (LPG) Fueled Vehicles at Different Ambient Temperatures

Compressed natural gas (CNG) and liquefied petroleum (LPG) are included in the group of promoted transport fuel alternatives for traditional fossil fuels Europe. Both CNG LPG fueled vehicles believed to have low particle number mass emissions. Here, we studied solid (SPN) emissions >4 nm, >10 nm >23 bi-fuel applying CNG, gasoline laboratory at 23 °C sub-zero (−7 °C) ambient temperature conditions. The SPN23 or operation modality were below regulated limit diesel direct injection 6×1011 1/km. Nevertheless, was exceeded temperatures, when sub-23 particles included, used as a fuel. key message this study is that gas-fueled produced mainly <23 current methodology might not be appropriate. However, only few cases absolute SPN emission levels 1/km Setting 1×1011 would also most