Over the years, energy is becoming an essential factor with an impact on social, economic, and environmental aspects. More than 2.5 billion people are connected to agriculture worldwide, so the importance of agricultural energy production has become increasingly important. This study provides a comprehensive review of renewable energy, environment, and farm publication trends. Two hundred articles from 1988 to 2022 were analyzed, with special attention devoted to the last three extreme years, using the Scopus database and the Bibliometrix tool for analysis and visualization. Research on this topic experienced significant developments after 2008, with many fluctuations being revealed. Historically, China and the USA were the most productive countries in agricultural energy production advancements. However, in the last three years, the research center’s respective contributions have undergone major changes. China maintained its dominance, but the importance of the USA fell sharply, and new centers (India, Poland) appeared. Biogas is the most popular method which is used and searched in this area between 1988–2022 since it includes both sustainability and locality. However, between 2020–2022, the importance of the circular economy has been highlighted in the literature. Complex energy systems, dual use of land, and energy storage might be the most important challenges for future research.

The energy use of residues from agriculture, forestry, and solid waste can foster the transition towards a more renewable energy supply. This paper analyzes the energy potential of the above-mentioned sources for energy applications in Kosovo. The analysis is based on statistical data from different studies and reports, analyzing and calculating them to determine the theoretical and energy biomass potential. Kosovo can increase its self-sufficiency by taking advantage of its rich but under-utilized potential of biomass energy sources. This is a novelty study in this area, considering Kosovo lignite-dominated heat energy and electricity consumption and the available special literature. According to our estimates, the theoretical potential is 6.13 million tons/year, while the biomass energy potential should be around 4.57 million tons/year, including approximately 74.6% of biomass, which can be used for energy needs (heating and electricity). Based on the data and calculations, the available and usable potential shows biomass as an energy source with high potential in Kosovo; its share is very low, but it is reasonable to grow for both environmental and economic reasons.

Our results introduce the preferences and attitudes of farmers and the internet-orientated population regarding renewable energy sources (RES) in Kosovo. The research included 243 internet-orientated participants and 30 farmers. The data was gathered through questionnaires (in both groups) and deep interviews (just in farmers). The results showed that the awareness of RES was high for especially solar, wind and hydro energy, the relationship among them was very strong. It was justified that firewood was typically used by respondents with low income, but not considered as renewable energy source, similarly to Hungary and the USA. A special feature of Kosovo is that electricity has very high importance for the man in the street, even for heating. Better education, higher income and environmental-consciousness definitely support better knowledge of RES, similarly to international tendencies. Males and employed participants had more knowledge about RES than females, or unemployed ones. Moreover, the results showed that the participants prefer environment rather than convenience, which is also typical of less wealthy countries. Our results might be useful as a typical less developed country case study for international comparison and helps to eliminate the unknown willingness in RES for the development of future agricultural strategies in Kosovo.

Agriculture accounts for a significant economic share in less-developed countries, especially Kosovo, where there is a lignite-dominated energy supply. Lignite’s partial replacement with locally produced renewable energy sources could play an essential role in reducing farmers’ costs and preparing the country for EU accession. Using a sample of 120 farmers, the Best–Worst Scaling (BWS) technique was used to assess farmers’ preferences for renewable energy applications and to measure the importance of seven key characteristics associated with the willingness to become energy self-sufficient. The results show a significant preference for “lower energy costs” and “environmental friendliness”. Using cluster analysis, it is shown in a statistically reliable way that while the decisions of smaller farms are influenced by economic factors and the role of energy self-sufficiency is negligible, a non-negligible share of larger farms already have already adopted self-sufficiency in energy production (solar panels, byproducts) and also consider the environment and convenience aspects necessary in their decisions. Farmers play an important role in local economic development. Therefore, regulatory schemes with differentiation by farm size may play an important role in promoting local energy management in Kosovo and similar less developed countries.

The energy crisis has highlighted the need for a significant change in Kosovo’s lignite-based electrical energy system, particularly greater investments in renewable energy sources. These sources would provide greater price stability, centralized accessibility, and relatively affordable investment costs. This research tries to analyze the basic attitudes behind the behavior of the students from the agricultural faculty in Kosovo in order to acquire a better understanding of their preferences for renewable energy source purchases, using the Best–Worst Scaling (BWS) method and cluster analysis. Students’ perspectives on renewable energy show strong environmental and price conscientiousness in BWS methods (first and second rank), while the rate of eco-skeptic students reaches only 23% in the cluster analysis, which is a very promising sign of the younger generation’s growing dedication to sustainability. Students, as future decision-makers, can play a critical role in making the transition to a more sustainable and resilient agricultural system. Green transition in Kosovo can be reached by combining the importance of dissemination and marketing tools with the pressing demand for renewable energy solutions, which might be interesting not only for Kosovo, but (considering the expectable enlargement) also for the EU.

Most of the energy content of wastewater can be found in wastewater heat, however, its recovery is limited. In this article, the current situation, future opportunities of wastewater heat recovery are presented based on secondary data collection, mentioning the constraints and main influencing factors of sustainable implementation of heat recovery systems in Hungary. Besides, the already existing systems are described. As regards the capacities of treatment plants, 103 of the 574 domestic plants have a capacity of over 20,000 Population Equivalent (PE), of which 25 plants have a capacity of over 100,000 PE. According to our calculations, in big cities/capitals (20.000 – 100.000, and over 100.000 inhabitants), it may be possible to recover wastewater heat sustainably in several places. In small towns (5.000 – 20.000 inhabitants), wastewater heat recovery can be technologically and economically sustainable only in the presence of agricultural or industrial plants with high and continuous wastewater feed into the pipeline system. Taking into account the temperature conditions at each place of use and their estimated fluctuations, it can be said that proper, careful planning, sizing and implementation have a crucial effect on the efficiency of microbiological activity in the treatment plants. In bigger cities, of course, the effect of the temperature drop of one main collector may be minimal, however, in smaller and medium-sized settlements, excessive heat extraction may result in complete inhibition or cessation of nitrification. In Hungarian case studies, the maximum acceptable temperature drop is approx. 2-3 °C. It can be stated that energy recovery from wastewater may be very promising considering the size and temperature limitations. Therefore, the rational recovery of wastewater heat can be an important part of the implementation of circular economy and sustainable energy utilization in wastewater management, resulting in significant energy savings and pollutant reduction. JEL CODE: Q25