Abstract
This paper discusses generally the possibility of reduction carbon dioxide emissions from internal combustion engines of vehicles (M and N categories) by using biomethane. The paper discusses such issues as: emission of greenhouse gases from European Union and Poland transport; rationality of current and future reduction of emission of greenhouse gases such as carbon dioxide from European Union road transport; the above-mentioned possibility of reduction carbon dioxide emissions from combustion engines of M and N category vehicles by using biomethane. The paper also described the EU strategy within the frameworks of alternative fuels. The research on the available vehicles has been done on the chassis dynamometer at the Motor Transport Institute (MTI). The research conducted in the driving cycles NEDC, D1 and D2 (developed in MTI) prove that emissions of carbon dioxide from spark ignition engines of M and N category vehicles, which are in service, can be substantially reduced by admission them with compressed natural gas (CNG) instead of petrol. At the same time it needs to be underscored that the research has been conducted on vehicles factory-adapted to use CNG. Considering spark ignition engine vehicles, which are adapted in service to use CNG, the differences can be even greater according to the quality of the modifications. When comparing vehicles with compression ignition engines of the aforementioned categories with the vehicles powered by CNG, the findings on carbon dioxide emissions demonstrate that emission is lower from vehicles with compression ignition engine or similar for both types of vehicles. Emission of CO2 by the above-mentioned categories vehicles tested under real traffic conditions is different from that occurring in type approval.
KEYWORDS – vehicles M and N categories, combustion engines, carbon dioxide, biomethane