This study investigates the performance assessment of methanol and water as working fluid in a solar-powered vapour absorption refrigeration system. This research clarifies the system’s performance across a spectrum of operating conditions. Furthermore, the HAP software was utilized to determine and scrutinize the cooling load, facilitating a comparative analysis between software-based results and theoretical calculations. To empirically substantiate the findings, this research investigates methanol-water as a superior refrigerant compared to traditional ammonia- water and LiBr-water systems. Through experimental analysis and its comparison with previous research, the methanol-water refrigeration system demonstrated higher cooling efficiency and better environmental compatibility. The system’s performance was evaluated under varying conditions, showing that methanol-water has a 1% higher coefficient of performance (COP) compared to ammonia-water systems, proving its superior effectiveness in solar-powered applications. This empirical model acts as a pivotal tool for understanding the dynamic relationship between methanol concentration (40%, 50%, 60%) and system performance. The results show that temperature of the evaporator (5–15 ℃), condenser (30 ℃–50 ℃), and absorber (25 ℃–50 ℃) are constant, the coefficient of performance (COP) increases with increase in generator temperature. Furthermore, increasing the evaporator temperature while keeping constant temperatures for the generator (70 ℃–100 ℃), condenser, and absorber improves the COP. The resulting data provides profound insights into optimizing refrigerant concentrations for improved efficiency.

In this research, we employed multivariate statistical methods to investigate the perspectives of small and medium-sized enterprises (SMEs) concerning the Extended Producer Responsibility (EPR) regulation and their apprehensions related to EPR compliance. The EPR regulation, which places the responsibility of waste management on producers, has significant financial and administrative implications, particularly for SMEs. A sample of 114 businesses was randomly selected, and the collected data underwent comprehensive analysis. Our findings highlight that a notable proportion of businesses (44.7%) possess knowledge of the EPR regulation’s provisions, whereas only a marginal fraction (1.8%) lacks sufficient familiarity. We also explored the interplay between opinions on the EPR regulation and concerns regarding its financial and administrative implications. Our results establish a significant correlation between EPR regulation opinions and concerns, with adverse opinions prominently influencing concerns, particularly regarding financial burdens and administrative workloads. These outcomes, derived from the application of multivariate statistical techniques, provide valuable insights for enhancing the synergy between environmental regulations and business practices. EPR regulation significantly affects SMEs in terms of financial, administrative, and legal obligations, thus our study highlights that policymakers may need to consider additional support mechanisms to alleviate the regulatory burden on SMEs, fostering a more effective and sustainable implementation of the EPR regulation.

Our study focusses on the sustainable finance framework of the European Union. Given that the concept, target system and practical implementation of sustainability have become one of the top priorities, we consider it important to present in an understandable and simple form what activities and regulations have been created in this regard within the scope of the European Union’s common policy. Starting from the concept of sustainability, we analyse its significance. We examine the economic, social, corporate governance and environmental pillars and the European Green Deal based on them as foundations, as well as some prominent elements of sustainable finance: the Taxonomy, the Corporate Sustainability Reporting Directive, the Sustainable Finance Disclosure Regulation and the Union’s Corporate Sustainability Due Diligence Directive. We review the relationships and interactions of the above elements. We describe the sustainability objectives of the European Green Deal and the resources related to them, as well as the Sustainable Finance package of the European Commission. We also provide an overview of the regulatory details of the above-mentioned elements of EU law, thereby making the complex and complicated process of regulation transparent. These issues are relevant to Hungary and other EU member states located in Central and Eastern Europe and they have an effect on their policies.

This study evaluates the aquafeed self-sufficiency sector in Indonesia, aiming to provide policy recommendations for optimizing freshwater aquaculture production. The study engaged 1005 participants, including 204 self-sufficient aquafeed producers and 801 fish farmers, covering 88% of the regions where the Ministry of Marine Affairs and Fisheries promotes aquafeed self-sufficiency, conducted in 30 Indonesian provinces. The majority of on-farm and small-scale feed manufacturers continue to operate successfully (91%), with a minor portion discontinuing (9%). Aquafeed products incorporating local ingredients prove cost-effective and receive high acceptance among fish farmers. The sustainability of the aquafeed self-sufficiency sector is closely linked to local ingredient availability, operational aquafeed manufacturing plants, product quality, human resource capabilities, and government policies. The study presents policy recommendations to address these issues, encompassing measures such as ensuring ingredient supply sustainability, providing a mobile laboratory for ingredient and feed analysis, enhancing human resource quality through training, facilitating easier access to financial support, and strengthening central-local government coordination to optimize the aquafeed self-sufficiency program. The rise of the national fish production target from freshwater aquaculture has attracted great attention in the improvement of the aquafeed sector since the sustainability of aquafeed supply is the main driver for the success of aquaculture production.

In marginalized ecosystem-dependent rural communities, access to ecosystem services plays a crucial role in achieving sustainable livelihoods. This study was conducted to find out the influence of various livelihood capital components on the access mechanism for forest-based Provisioning Services (PS) in some selected villages of the Gosaba Block on the fringes of the Sundarban. The contribution of the livelihood capitals to gain access to Provisioning Services (PS) was identified using factor analysis on 160 households, selected through cluster random sampling. The sustainability levels of livelihood capitals were analyzed using the Prescott-Allen method (2001). The natural, financial, social, and physical capitals were significantly below average, while the human capital was close to average. Enhancement of human, physical, financial, and social capital, ease in issuing Biometric Fisherman cards for entering forests, flexibility in borrowing loans, and ecotourism by involving local villagers must be encouraged to enhance forest-based provisioning services in the near future.

The construction industry is responsible for over 40% of global energy consumption and one-third of global greenhouse gas emissions. Generally, 10%–20% of energy is consumed in the manufacturing and transportation stages of materials, construction, maintenance, and demolition. The way the construction industry to deal with these impacts is to intensify sustainable development through green building. The author uses the latest Green Building Certification Standard in Indonesia as the Green Building Guidelines under the Ministry of Public Works and People’s Housing (PUPR) Regulation No. 01/SE/M/2022, as a basis for evaluating existing office buildings or what is often referred to as green retrofit. Structural Equation Modeling-Partial Least Squares (SEM-PLS) is used by the authors to detail the factors influencing the application of green building by analyzing several variables related to the problem studied, which are used to build and test statistical models of causal models. From this study, it is concluded that the most influential factors in the implementation of green retrofitting on office buildings are energy savings, water efficiency, renewable energy use, the presence of green building socialization programs, cost planning, design planning, project feasibility studies, material cost, use of the latest technology applications, and price fluctuations. With the results of this research, there is expected to be shared awareness and concern about implementing green buildings and green offices as an initiative to present a more energy-efficient office environment, save operating costs, and provide comfort to customers.