This article examines the current state of renewable energy sources (RES) in the Visegrad Four (V4) countries in the context of historical developments and the influence of national policies. The primary aim of this study is to compare progress, challenges, and opportunities in RES development across the V4 countries between 2014 and 2022, using standardised per capita indicators and combining political and technical analyses. Our methodology involves analysing statistical data from Eurostat and the IEA, conducting a qualitative assessment of RES support policies, and performing ANOVA to verify the statistical significance of differences between countries. The findings suggest that countries such as the Czech Republic and Hungary have made significant progress in decarbonising their energy sectors. At the same time, Poland and Slovakia face greater challenges—Slovakia, in particular, due to its greater reliance on biomass and political turbulence. Poland has long lagged in developing RES, mainly due to its strong dependence on coal, but it is now becoming a leader in implementing RES within the V4. The main obstacles to the development of RES include insufficient political and legislative support and administrative barriers that hinder the adoption of new technologies. Another critical factor is public concern about the potential negative impacts of RES on quality of life, which may stem from a lack of information and education in this area, as well as from political intentions. To improve the situation, it is necessary to increase transparency, provide relevant education, and involve local communities in decision-making processes. Ensuring a stable political and legislative framework and adequate financing are key to achieving ambitious renewable energy targets in the region.

Operational research is a significant part of management, based on improving efficiency, operability, and machine quality. Those improvements influence the time of the repair process, workforce availability for the repair process, safety, and environment. The main goal of this article is to investigate the optimal – operating service life of the machine and the optimal – operating time interval for the renewal of the CNC metalworking machine. The research was implemented in a small enterprise in Slovakia that needed a CNC machine in the production process. The research hypothesis was determined H1: Using quantitative models of operational research can manage the machine’s life cycle. We used quantitative mathematical models of operational research. By calculation, we found that the optimal – operational lifetime of the CNC machine is 6 years. The renewal time of the machine is between the 5th and 6th year of use with a minimal level of the total costs for repairs and maintenance. This simulation is essential information for the financial plan for CNC machine renewal. The results of the research showed a confirmed hypothesis. The suggested proactive model is a viable instrument for the machine park in small enterprises with various orientations.

This study benchmarks renewable energy source (RES) utilization in the Visegrad Four (V4) against the EU average using Eurostat data for 2014–2022. A multi-layer framework was used to combine technology-specific per-capita indicators, sectoral RES shares, cluster analysis, and panel regression with fixed effects. The EU substantially exceeds V4 in hydropower (774.06 vs. 270.19 kWh/person), wind (972.06 vs. 161.30 kWh/person), and solar technologies. The electricity-sector gap is most pronounced (EU 41.17% vs. V4 18.69%). Paired t-tests confirmed a statistically significant persistent gap (t(8) = −20.78; p < 0.001), consistent with delayed convergence. Cluster analysis assigned all V4 countries to a single moderate-RES tier, structurally separated from Western and Nordic clusters; panel regression confirmed that the V4 coefficient was robustly negative (β = −5.783 to −9.088 pp) even after policy controls, with fossil lock-in (β = −2.404 pp) emerging as the most consistent structural determinant, whereas V4 × fossil lock-in interaction was positive (β = +2.558 pp), suggesting partial mitigation through differentiated pathways. Intra-V4 heterogeneity—Slovakia’s hydropower lock-in, Hungary’s wind prohibition, Poland’s coal dependency, and Czech Republic’s curtailed feed-in tariff—argues against homogeneous policy responses; results support technology-specific strategies (wind/solar PV in Poland/Czech Republic; solar thermal/heat pumps in Hungary/Slovakia) and grid modernisation as cross-cutting priority.

For the European Union in the field of raw material policy, it is primarily important to ensure reliable, seamless, and unrestricted access to raw materials in all EU countries. An important aspect in assessing the European Union’s raw material policy is a detailed analysis of selected significant raw materials. This paper focuses on raw material policy within the European Union (EU). Specifically, it examines five types of raw materials: critical raw materials, metal ores, non-metallic minerals, fossil energy materials, and biomass. The research is oriented to analyzing the materials from the perspectives of consumption, mining, export, and import. The objective is to assess the European Union’s (EU) raw material policy by employing specific tools and statistical methodologies to analyze individual data. We aimed to assess the European Union (EU) raw material policy using selected statistical methods such as regression and correlation analysis, multivariate analysis, and pairwise correlation to reveal and describe the relationships between variables. Based on the examination of import and export data, it is evident that imports are on the rise while exports are declining. This trend underscores the EU’s continued reliance on raw materials sourced from other global regions. The results show that domestic production and consumption are sufficient; on the other hand, the EU remains dependent on imports of critical raw materials. The results are useful for the development of future EU raw material policy.