The Influence of Power Sources for Charging the Batteries of Electric Cars on CO2Emissions during Daily Driving: A Case Study from Poland

The main sources of greenhouse gas emissions and air pollution from the transport sector are diesel- and gasoline-powered passenger cars. The combustion of large amounts of conventional fuels by cars contributes to a significant release of various compounds into the atmosphere, such as solid particles, nitrogen oxides, carbon monoxide, and carbon dioxide. In order to reduce these pollutants in places of their high concentration (especially in urban agglomerations), the use of ecological means of transport for daily driving is highly recommended. Electric vehicles (EV) are characterized by ecological potential due to their lack of direct emissions and low noise. However, in Poland and many other countries, electricity production is still based on fossil fuels which can significantly influence the indirect emissions of carbon dioxide into the atmosphere associated with battery charging. Thus, indirect emissions from electric cars may be comparable or even higher than direct emissions related to the use of traditional cars. Therefore, the aim of the work was to analyze the amount of carbon dioxide emissions associated with the use of electric vehicles for daily driving (City, Sedan, SUV) and their impact on the environment on a local and global scale. Based on the assumed daily number of kilometers driven by the vehicle and the collected certified catalog data (Car Info Nordic AB), the direct emissions generated by the internal combustion engines (ICE) were calculated for specific cars. These values were compared to the indirect emissions related to the source of electricity generation, for the calculation of which the CO(2)emission coefficient for a particular energy source and energy mix was used, as well as reference values of electricity generation efficiency in a given combustion installation, in accordance with the KOBiZE (The National Centre for Emissions Management) and European Union regulation. Indirect emissions generated from non-renewable fuels (lignite, hard coal, natural gas, diesel oil, heating oil, municipal waste) and renewable emissions (wind energy, solar energy, hydro energy, biomass, biogas) were considered. The results indicated that for the Polish case study, indirect carbon dioxide emission associated with the daily driving of EV (distance of 26 km) ranges 2.49-3.28 kgCO(2)center dot day(-1). As a result, this indirect emission can be even higher than direct emissions associated with ICE usage (2.55-5.64 kgCO(2)center dot day(-1)).