Abstract
The primary aim of this study was to assess and classify selected EU countries to groups differing in terms of the degree of implementation of innovative energy technologies to alleviate adverse externalities in road transport. This aim was realised using three groups of research methods: collection of empirical data, data processing and presentation of study outcomes. When collecting the research material, the authors used the method of critical literature review and the documentation method. The research material was processed using the agglomerative clustering technique, which was one of the hierarchical clustering methods. The distance between objects (here, selected EU countries) was determined based on the Euclidean distance. The outcome of this analysis was a dendrogram, which constitutes a graphical interpretation of obtained results. The study was conducted on 21 EU countries. The analyses covered the years 2013−2019. The sources of materials included literature on the subject and the Eurostat data. The problem of innovative energy technologies in road transport is presently of considerable importance. This results from the current situation related to human activity. As a result of the conducted cluster analysis, groups were distinguished based on differences in the use of innovative energy technologies alleviating negative externalities generated by road transport. The first group comprised Sweden, the Netherlands and Finland. Compared to the other groups, this group was distinguished by the highest values of four indexes, i.e., the share of renewable energy sources used in transport in 2019, the share in the market of electric passenger vehicles in 2019, the share in the market of electric lorries in 2019, as well as the share in the market of hybrid automobiles in 2019. Countries which participated the least in the elimination of negative externalities generated by road transport included Romania, Hungary, Greece, Poland, Latvia and Estonia.