CLUSTER ANALYSIS OF THE MEMBER COUNTRIES OF THE EUROPEAN UNION ACCORDING TO ENERGY, ENVIRONMENTAL AND ECONOMIC INDICATORS
Abstract: In this paper, a cluster analysis was conducted to group the European Union member states according to energy, environmental and economic indicators for 2023. The selected variables are GDP per capita, the share of renewable energy sources in total energy consumption and CO₂ emissions per capita. The aim of cluster analysis is to group the European Union member states based on economic, energy and environmental indicators in order to identify their mutual similarities and differences. The analysis begins with a hierarchical clustering method using the Ward method with squared Euclidean distance. The dendrogram indicated several potential solutions, and particular attention was paid to solutions with three and five clusters. The observed clusters reflect differences in the level of development and approach to energy policy. Countries with higher levels of economic development are characterized by a lower degree of sustainability due to a lower share of renewable energy sources and high greenhouse gas emissions. Conversely, less developed countries achieve better results according to environmental sustainability indicators, but at the same time have limited economic growth potential. To confirm the stability of the clusters, the K-means method, i.e. a non-hierarchical method, was also applied, which further refined the grouping. The results of the discriminant analysis showed high classification accuracy, confirming the reliability of the model. In conclusion, the cluster analysis provided a deeper insight into energy and environmental patterns within the EU, highlighting the need for harmonization of sustainable policies among members with different levels of economic development. The results obtained can serve as a basis for designing targeted and differentiated policies within the EU that take into account the specificities of each group of countries, with a particularly important balance between economic growth and environmental sustainability.
Keywords: European Union, GDP per capita, renewable energy sources, CO₂ emissions, cluster analysis