The main objective of this article is to evaluate the repercussions of the crises resulting from the COVID-19 pandemic and the war in Ukraine on changes to the European Union’s reliance on energy raw material imports, particularly from Russia. Furthermore, several specific objectives are outlined: to ascertain the EU’s energy balance and any alterations therein, to identify changes in the concentration of energy raw material imports among EU countries during the crises, to determine the level and fluctuations in energy raw material import dependence within the EU and individual member states throughout the crises, and lastly, to assess changes in the concentration of energy raw material imports from Russia in EU countries during the crises. The research encompassed all 27 EU member states as of 31 December 2022, and the examination period spanned 2010 to 2022. The information sources include relevant literature on the subject and data sourced from Eurostat. In conducting the analysis and presenting the data, several methodologies are employed, including descriptive, tabular, and graphical techniques. Additionally, quantitative measures such as the Gini structure concentration coefficient and concentration analysis via the Lorenz curve are utilized. In the initial phase, an analysis of changes to the energy balance of the entire EU in the period before and during the COVID-19 pandemic and the war in Ukraine was carried out. Changes to the concentration of energy imports in EU countries during crises are also shown. Secondly, dependence on imports of individual energy resources for the entire EU was identified. Various changes in this relationship during crises are shown. If the dependence of the entire EU on the import of individual groups of energy resources from Russia were identified, changes in individual EU countries in this respect are indicated. Finally, the changes in the concentration of energy imports from Russia in the EU countries during the crises are shown. During the COVID-19 pandemic, the EU experienced a slight reduction in dependence on energy raw material imports. However, this reduction was short-lived and mainly attributed to the decrease in energy demand caused by the pandemic. Conversely, the war in Ukraine had a substantial impact, leading to a notable surge in energy raw material imports as a result of stockpiling efforts and the need to safeguard against further disruptions in the energy market. Notably, the EU’s reliance on energy imports from Russia was already considerable. Following the outbreak of the conflict in Ukraine, imports of oil, petroleum products, and solid fossil fuels experienced significant decline due to imposed sanctions. Nonetheless, restrictions on natural gas imports were comparatively less severe. In 2023, imports of crude oil instead of petroleum products practically ceased, while restrictions in the case of natural gas were not so drastic.

The use of green and renewable energies undeniably plays an essential role in today’s society. Energy from these sources plays a key role in transforming the energy sector and significantly impacts the way of life and the quality of life of different social groups. The main aspects of this study are to briefly describe the situation of clean and renewable energy in Hungary and to investigate the extent to which the younger generation of different social groups is involved in using renewable energy sources in their everyday lives and their attitudes towards environmental awareness. In our research, we also investigate whether there is a strong statistical correlation between environmental awareness, environmentally damaging activities and the perceptions of different environmental problems among the target groups and, if so, how these affect the research topic. Our primary research can be considered representative, as we surveyed all primary and secondary school students in the Gyöngyös micro-region of the North-Hungarian region and also included the opinion of university students in the mentioned micro-region. The questionnaire was asked in person, and 2180 students completed it. The research was carried out in several phases, the first occurring between 2017 and 2019 and the second between 2020 and 2021. Three research questions were formulated, and the main findings show that the students’ main goal in the research was not to protect or support the environment but to prefer material well-being and related factors. On the results of statistical correlation analyses, overall, the examination by educational level (primary, secondary and higher) does not show significant differences between student groups, i.e., students with higher education do not have higher levels of environmental awareness and attitudes. Another important finding is that using renewable energy sources is considered too expensive for low-income families to take advantage of this kind of energy.

The main objective of this article is to identify the direction of change in logistical activities and their critical segments as a result of the COVID-19 pandemic in a country that is an important logistical hub of Europe. The specific objectives are to identify changes in logistical activities, especially during the COVID-19 pandemic, to determine the dynamics of changes in business revenues and in quantitative parameters for total logistics services and their segments during the pandemic, to establish the relationship between the economic situation and parameters related to logistics services, including during the COVID-19 pandemic. Using the method of purposive selection, Poland, which is well developed in logistics and aspires to be a crucial logistical hub of Europe, was selected for the study. The analysed period covered the years 2015–2021. The material sources were the literature on the subject and data from reports on individual logistics segments. Dynamic indicators with a fixed and variable base, coefficient of variation and Kendall’s tau correlation coefficient were used for analysis and presentation. It was found that the COVID-19 pandemic accelerated changes in logistics activities. These changes included digitalisation, the development of the e-commerce market, multi-channel sales and the development of these services, and the introduction of automation and artificial intelligence. In all activities, 2020 was the most challenging year, but there was generally a reduction in revenue growth and, less often, stagnation. Logistics companies gained in the second year of the pandemic (2021) when implemented solutions generated record revenues. Among the winning segments were logistics services in general, especially sea freight forwarding, warehousing services, courier services related to e-commerce, and a lesser extent, freight transport. Losses were incurred in the segment related to passenger transport. COVID-19 became a positive catalyst for change. The logistics industry ultimately benefited from the pandemic. Additionally, due to the pandemic, logistics operations have had greater sustainability, contributing to resource conservation and environmental protection.

In recent years, the importance of energy efficiency in the agricultural sector has become increasingly apparent. As the world faces challenges such as climate change, resource scarcity, and population growth, the need for sustainable and efficient agricultural practices has intensified. Energy plays a crucial role in agricultural production, from powering machinery and irrigation systems to processing and transportation. Therefore, understanding the scientific advancements and collaborative efforts in the field of energy efficiency in agriculture is essential for devising effective strategies, promoting innovation, and achieving global sustainability goals. The aim of this study is to provide insight into and a comprehensive overview of global publications on energy efficiency in agriculture and examine its scientific productivity. The paper explores the research areas and trending topics within the field, as well as the extent of collaboration among authors, institutions, and countries involved in this scientific domain. This investigation is crucial in order to address the current energy shocks and the numerous problems they generate, highlighting the importance of a holistic approach and the need for multiple regions to work together. Only by offering rapid and viable solutions can we effectively overcome this situation.

The objective of this article was to investigate the impacts of climate change on photovoltaic systems among renewable energies by the end of the 21st century. One hypothesis posited that due to decreased cloud cover as a result of changing climate, the geographical region under examination would receive more solar irradiation—usable by photovoltaic panels—which would in turn increase the annual electrical energy production of these systems. Another hypothesis suggested that the average temperature increase, associated with changing climate conditions, would detrimentally affect the efficiency of electricity production in photovoltaic systems. The study was based on the simulation of a household-scale photovoltaic model. This simulation calculated the system's performance on an hourly basis depending on inputs and summed these to produce an annual value. Input values were derived from climate scenario databases. These variables included global horizontal irradiance, direct horizontal irradiance, temperature, and wind speed. The output was the aforementioned quantity of annual electrical energy production. An analysis occurred between the annual average global horizontal irradiance and the annual average air temperature in relation to the quantities of annual electrical energy production. Pearson and partial correlation examinations among the variables demonstrated that unfavorable scenarios resulted in reduced efficiency of photovoltaic electrical energy production, primarily due to rising temperatures. Among other contributions, this article can support research into the active cooling of photovoltaic systems and the examination of their viability to mitigate efficiency losses caused by current and future temperature increases. Doi: 10.28991/HIJ-2024-05-01-01 Full Text: PDF

Energy is vital for the proper functioning of the various sectors of the economy and social life. During the pandemic, there have been some changes in these aspects that need to be investigated. The main objective of this article is to identify the direction of change caused by the COVID-19 pandemic in energy consumption and energy intensity in sectors and economic areas in EU countries. The specific objectives are to identify the importance of energy consumption in sectors and areas of the economy in individual EU countries; to determine the dynamics of change and variability during the pandemic in energy consumption in individual sectors and areas of the economy in EU countries, especially during the COVID-19 pandemic; to determine the changes in energy intensity of individual economic sectors and the differences in energy intensity between individual EU countries, including during the COVID-19 pandemic. Using a purposive selection method, all 27 EU Member States were selected for the study on 31 December 2020. The analysed period covered the years 2005–2020. The sources of material were literature and data from Eurostat. Descriptive, tabular and graphical methods, dynamic indicators with a fixed base and variable base, Gini coefficient, coefficient of variation, Pearson’s linear correlation coefficient, and multi-criteria analysis were used for analysis and presentation. It was found that the structure of energy consumption had remained unchanged for several years, with transport, industry and households dominating. There were no significant differences between countries. The COVID-19 pandemic reduced energy consumption in all sectors of the economy, the largest in transport and services and the smaller in industry. At the same time, household energy consumption increased. As a result of the pandemic, there was an increase in energy intensity in all sectors of the economy, the largest in industry. Western European countries had a lower energy intensity of the economy than Central and Eastern European countries. There was little change over several years. Countries generally maintained their ranking. The pandemic did not change anything in this respect, meaning that it had a similar impact on individual EU countries.