The transition to refrigerants with low-GWP in residential heat pumps is driven by global regulations to reduce greenhouse gas emissions. R454B stands out as a promising alternative to R410A, due to its moderate GWP (531) and similar thermodynamic properties, making it ideal for compact brine-to-water heat pumps designed for indoor installation. However, R454B is mildly flammable (A2L), so its charge should be minimized without compromising performance. This aspect is particularly relevant in modern heat pumps equipped with variable speed compressors, which are increasingly used to meet stringent energy efficiency requirements. Despite numerous studies on R454B drop-in tests, research on the combined effect of refrigerant charge and variable-speed operation remains scarce. This paper investigates a brine-to-water heat pump originally designed for R410A and tested with R454B as a drop-in replacement. Experiments were conducted under EN 14511 and EN 14825 rating conditions for low- and intermediate-temperature space heating applications. The effects of refrigerant charge and compressor speed on heating capacity, COP, discharge temperature, and seasonal performance were analyzed. Results reveal that improper charge significantly affects the unit performance and operating limits, identifying an optimal charge range for maximizing COP and SCOP. Compared to R410A, R454B achieves slightly higher COP and requires less charge, though at the expense of lower heating capacities and higher discharge temperatures. A SCOP evaluation showed better performance with R454B at equal design heating load. These findings provide practical guidelines for optimizing R454B charge in variable-speed heat pumps, supporting its adoption as a lower-GWP alternative in residential applications. • The R454B charge impact in a domestic heat pump designed for R410A is analyzed. • Heat pumps without a liquid receiver are highly sensitive to the refrigerant charge. • Improper charge affects efficiency and operating limits in variable-speed systems. • An optimum refrigerant charge that maximizes the system COP or capacity was found. • R454B needs less charge than R410A and can achieve a higher SCOP.

Apply machine learning to predict greenhouse gas emissions in aerobic composting and achieve emission reduction by nanomembrane covering mode.

Combustion of biomass in existing coal-fired power plants is a promising near-term option for reducing greenhouse gas emissions—particularly when combined with oxy-fuel combustion and subsequent Carbon Capture and Storage (CCS). However, the scale-up of biomass oxy-fuel technology is hampered by the lack of high-fidelity experimental data from combustion chambers of industrially relevant thermal loads. In large-scale facilities, the application of advanced diagnostics is often restricted by limited optical access and harsh conditions, which is why many previous studies rely on conventional probe-based measurements. This study demonstrates the successful transfer of planar Particle Tracking Velocimetry (PTV) and direct Tunable Diode Laser Absorption Spectroscopy (TDLAS) to a semi-industrial combustion chamber. Experiments were conducted for air- and oxy-fuel atmospheres with oxygen volume fractions ranging from 27 % to 33 %, each under two swirl settings. PTV measurements delivered two-dimensional fields of the solid fuel particle velocities, while TDLAS provided information on gas-phase temperatures along several beam paths. The data presented in this work are the first of their kind for a semi-industrial biomass combustor, as comparable datasets were previously limited to laboratory-scale, optically accessible systems. The results indicate that the global particle velocity field and particle distribution are governed primarily by the swirl, with oxygen fraction causing secondary effects. For both swirl settings, the oxy-fuel case at 33 % O 2 most closely matched the corresponding air-fired particle velocity field. TDLAS measurements captured swirl-dependent temperature patterns. The acquired data provide a valuable basis for the validation of numerical simulations and for the design and optimization of future combustors. • Investigation of biomass combustion in semi-industrial 1 MW th combustion chamber. • Combustion in air and oxy-fuel atmospheres (27 % to 33 % O 2 ), with variation of swirl. • Measurement of particle velocities using 2D-PTV and gas temperature using TDLAS. • Flow field is dominated by swirl, oxygen fraction has secondary influence. • Flow field in an oxy-fuel atmosphere of 33 % O 2 is most similar to air-firing.

Optimizing green manure application for achieving reduced greenhouse gas emissions and sustained crop yields

Electricity generation by burning by waste material, also known as thermal waste-to-energy, is a process that involves converting waste material into electricity by burning them in a combustion chamber. This process is a sustainable solution for waste management as it reduces the volume of waste sent to landfills while producing renewable energy. The methodology, for electricity generation by burning waste material typically involves waste collection, handling, and preparation, incineration, energy recovery, and ash management. The generated electricity can be used to power local communities or industries or fed back into the national grid. The process of electricity generation by burning waste materials provides a reliable source of electricity while reducing greenhouse gas emissions by avoiding the release of methane gas from landfill.

ABSTRACT Farmers' adoption of climate change mitigation practices is crucial for reducing greenhouse gas (GHG) emissions from food production. One major source of these emissions is chemical fertilizer application. Introducing clover into grassland can mitigate emissions by reducing the need for chemical fertilizers. In this study, we conduct an information experiment with over 300 Irish dairy farmers to examine how information impacts their beliefs about clover adoption, and how this in turn influences subsequent intentions. Methodologically, we contribute to the literature by combining qualitative (i.e., open‐ended questions) and quantitative (i.e., point estimates) belief elicitation measures in our experimental design. This approach provides more detailed insights into farmers' beliefs, as it captures top‐of‐mind concerns without priming responses. Our qualitative belief elicitation reveals that after exposure to the information treatments, while most farmers did not change their opinions, some shifted from concerns such as ‘ bloat ’ and ‘ difficult ’ to terms like ‘ reduction ’ and ‘ possible ’. Our quantitative measures show that farmers underestimated clover's potential to reduce chemical fertilizer use. This finding is key for policymakers, as similar underestimations may apply to other GHG mitigation practices. Importantly, we provide causal evidence that information could reduce misperceptions. This highlights the need for strategies that positively shift beliefs to encourage more widespread uptake of climate change mitigation practices. Nonetheless, there was no meaningful impact of the updated beliefs on intentions, which underlines the complexity of adoption decisions.

The rapid global transition toward electric vehicles (EVs) represents a critical shift in the automobile industry, driven by the urgent need to reduce greenhouse gas emissions and achieve sustainable mobility. However, the adoption of EV technology in developing countries such as Bangladesh presents unique challenges, particularly due to climatic conditions, infrastructural limitations, and policy gaps. This thesis investigates the design and policy framework for climate-optimized electric vehicle battery systems in Bangladesh, with a focus on enhancing performance, safety, and long-term sustainability. A key challenge addressed in this study is the impact of Bangladesh’s tropical climate on lithium-ion battery performance. High ambient temperatures and humidity levels contribute to thermal stress, accelerated degradation, and reduced efficiency of battery systems. To address this issue, the research explores various battery thermal management systems (BTMS), including air cooling, liquid cooling, and phase-change materials, through simulation-based analysis. The objective is to identify the most effective and economically feasible solution suitable for local environmental conditions. In addition to engineering design, this study examines the current policy landscape governing electric mobility in Bangladesh. It identifies gaps in regulatory frameworks, infrastructure development, and technological adaptation that hinder the widespread adoption of EVs. By integrating engineering insights with policy analysis, the research proposes a comprehensive framework aimed at supporting the development of a resilient EV ecosystem. The findings of this study contribute to both academic and practical domains by offering a localized approach to EV technology adaptation while aligning with global sustainability goals. Ultimately, this research provides a foundation for future innovation, policy formulation, and international collaboration in advancing Bangladesh’s automobile sector toward a more sustainable and globally integrated future.

The escalating global challenge of waste management, combined with the urgent need to reduce greenhouse gas emissions, has intensified interest in waste-to-energy (WtE) technologies as integrated solutions for sustainable energy recovery. This review critically examines advanced WtE technologies through three interconnected dimensions: the strength of the evidence base supporting performance and environmental claims, the challenges associated with scalability and system integration, and the implications of these technologies for net-zero energy transitions. The analysis covers thermochemical, biochemical, and hybrid conversion pathways, including pyrolysis, gasification, hydrothermal liquefaction, and anaerobic digestion, with particular emphasis on identifying inconsistencies in the literature and clarifying key uncertainties. A persistent gap between laboratory-scale performance and commercial-scale operation is identified and characterised across conversion pathways. Its principal drivers of feedstock heterogeneity, heat transfer limitations, and operational complexity are examined. Environmental assessments are shown to be highly sensitive to system boundary definitions and carbon accounting methodologies, with lifecycle results varying substantially depending on energy substitution assumptions and biogenic carbon treatment. The integration of WtE within circular economy frameworks demonstrates that energy recovery is most effective when positioned as a complement to material recycling rather than a substitute. The roles of combined heat and power configurations, district heating, carbon capture and storage, and emerging reactor technologies in advancing net-zero contributions are assessed. Significant data gaps are identified in long-term operational performance, modelling transparency, and reporting standardisation. The review concludes that WtE technologies represent valuable components of integrated waste and energy management systems, but their long-term contribution to decarbonisation requires careful system design, sound operational strategies, and harmonised performance evaluation frameworks.

Purpose To combat global warming, governments worldwide have established policies aimed at reducing greenhouse gas emissions. Meanwhile, major organizations across diverse industries are taking proactive steps to minimize CO2 emissions. As centers of innovation and scientific inquiry, universities in the education sector have established bold CO2 reduction goals. This study employs the Spatial Panel model. This approach treats different geographic regions as a spatial panel, accounting for correlations between regions in the regression analysis. Design/methodology/approach We examined the relationship between environmental research, environmental quality, education quality, eco-friendly behavior, climate change contribution, climate action and information technology (degree awarded by information technology) on carbon dioxide emissions at the top 100 US universities between 2015 and 2024. The effect of each state's condition was examined on neighboring states. Findings The results showed that environmental research and climate action (with a negative sign) have the greatest impact on CO2 emissions. The environmental quality, education quality, eco-friendly behavior, climate change contribution and information technology also have an impact on CO2 emissions. This study suggests that effective environmental policy integration, regulation and enforcement are vital for monitoring environmental changes and advancing research initiatives in universities. Originality/value This study features: A spatial panel model considering neighboring effects in the United States, a large sample of top US universities with recent data (2015–2024) and some additional variables: Environmental research, Environmental quality, Education quality, Eco friendly behavior, Climate change contribution, Climate action and Information Technology, exploring their roles on CO2 emissions.

Abstract As China’s capital, Beijing has significantly improved its air quality, yet the synergistic reduction of atmospheric pollutants and greenhouse gases remains a critical challenge. This study pioneers an integrated modeling framework that couples the Long-range Energy Alternatives Planning system (LEAP-Beijing), Marginal Abatement Cost (MAC) analysis, and the WRF-Chem air quality model. This approach simulates Beijing’s energy-emission pathways from 2030 to 2050, techno-economically evaluates 37 mitigation technologies, and quantifies their resultant air quality impacts. Our findings identify an enhanced energy mix scenario as optimal, achieving reductions of 59.29% in CO₂ and 81.34% in NOx. Key measures included battery-electric trucks (transportation), building envelope retrofits (buildings), and photovoltaic power expansion (electricity). The comprehensive implementation of selected technologies could lead to reductions in both PM2.5 and NO2 concentrations by 6% and 24%, respectively, although wintertime ozone levels would increase by 10%. The findings highlight the need to strengthen targeted end-of-pipe control measures for dust and volatile organic compounds (VOCs) alongside carbon reduction efforts, in order to maximize the co-benefits of climate change mitigation and air quality improvement.

In the 21st century, the desire for improved fuel efficiency of engines, lower fuel prices, and the need to reduce greenhouse gas emissions such as CO2 and NOx are leading the aviation industry to seek hybrid-electric jet engines for commercial aircraft. These aircraft will have greater maintenance challenges due to additional components requiring more reliable materials for the engine’s parts, such as turbine blades. Turbine blades must be composed of materials that have enhanced fatigue performance. Resistance to dynamic loads and high strength will be needed to ensure modern gas turbine blades are as reliable as possible. This review paper examines hybrid-electric engine turbine blades and subsequently introduces additive manufacturing (AM) and multi-principal element alloys (MPEAs) with a focus on laser powder bed fusion (LPBF), high-entropy alloys (HEAs), and medium-entropy alloys (MEAs). The tensile properties of LPBF HEAs range from 5 to 47% elongation and a UTS of 572–1640 MPa, while LPBF MEAs range from 8 to 73.9% and a UTS of 573–1382 MPa. This study focused on dynamic and fatigue properties while acknowledging gaps in high-temperature testing. The combination of mechanical properties with the ability to control internal geometry makes these AM alloys an attractive option for the next generation of gas turbine blades.

This study examines the mediating role of tax compliance in the relationship between carbon tax and environmental performance in the public sector of Indonesia. The implementation of carbon tax, aimed at reducing greenhouse gas emissions, faces challenges in Indonesia due to low tax compliance, potentially undermining its effectiveness. A total of 318 participants from public sector organizations in Indonesia were selected using random sampling for this study. Data were collected through an online survey, designed to measure tax compliance, carbon tax, and environmental performance. The results indicate that tax compliance significantly mediates and moderates the relationship between carbon tax and environmental performance, highlighting the importance of improving tax compliance to enhance the effectiveness of carbon tax policies. This study provides empirical evidence on the critical role of tax compliance in maximizing the environmental benefits of carbon taxes in developing countries like Indonesia, where tax culture and enforcement systems are still evolving. The findings contribute to the literature on carbon taxation by emphasizing the need for fostering compliance to ensure the success of environmental tax policies.

ABSTRACT Reaching global net‐zero targets has become an urgent priority as businesses and nations face increasing pressure to reduce greenhouse gas emissions. Achieving carbon neutrality in manufacturing supply chains requires comprehensive systemic changes across business processes. It demands forward‐looking strategies that guide companies toward long‐term sustainability and net‐zero objectives. While earlier research has identified several drivers and barriers, there remains a lack of clear, actionable roadmaps that companies can follow. This paper fills this research gap by determining 11 interdependent strategies and grouping them into six levels of hierarchy and discovering that they play the roles of driving and dependent. Results showed that important strategies consist of policy development and incentives, carbon accounting, collaborative learning, renewable energy adoption, low‐emission transportation, digitalization, and circular practices. Using expert insights and a multi‐round Delphi technique, the study identifies key strategies, which are then organized through total interpretive structural modeling (TISM) and cross‐impact matrix‐multiplication applied to classification (MICMAC) analysis. Results identify a pathway roadmap where strategies connect, allowing businesses to focus on initiatives including circular practices, digitalization, and waste reduction. Policy and incentives serve as essential tools, with companies responsible for turning concepts into key performance indicators. Our research offers a blueprint for global organizations to better align efforts, lower emissions, and work toward net‐zero. It outlines the relationship among the strategies and priorities needed by global companies and governments to develop effective cross‐border collaboration and coordinate sustainability efforts, thus supporting climate change commitments.

In the context of global efforts to reduce greenhouse gas emissions and air pollution, increasing importance is being attached to the accurate monitoring and analysis of emissions generated by means of transport, including commercial vehicles used in specialized applications. This article presents the results of research conducted on the emissions of harmful compounds from concrete mixers in real traffic conditions. The measurements were performed using the Axion R/S+PM portable emission measurement system from Global MRV, which enabled the mass measurement of emissions of pollutants such as CO, CO2, NOx and HC under real truck driving conditions. Based on the collected data, the time density characteristics of the tested compounds were determined as a function of crankshaft speed and engine load, and their emission intensity was determined as a function of vehicle speed. On this basis, the impact of changes in load weight on the obtained emission intensity values of the tested pollutants was demonstrated. The analysis of pollutant emissions from a heavy vehicle designed for transporting concrete made it possible to determine the impact of various road conditions and engine operation on the amount and type of compounds emitted. By monitoring operating parameters such as load and engine crankshaft speed, it is possible to gain a more accurate understanding of the mechanisms of exhaust emissions under actual vehicle operating conditions. In this way, it is possible to more effectively identify situations in which pollutant emissions are particularly high and to determine the optimal operating conditions for reducing emissions.

Sustainable Aviation Fuel is the most viable near-term strategy for decarbonizing commercial aviation. Its performance depends fundamentally on the quality of the feedstock and conversion efficiency. This paper examines the four principal ASTM-certified pathways: Hydroprocessed Esters and Fatty Acids (HEFA), Fischer-Tropsch Synthetic Paraffinic Kerosene (FT-SPK), Alcohol-to-Jet (ATJ), and Power-to-Liquid (PtL/eSAF). Additionally, it highlights how feedstock chemical composition, contaminants, moisture content, and carbon intensity affect conversion outcomes, including fuel yield, catalyst performance, minimum fuel selling price, and lifecycle greenhouse gas reduction. Feedstock cost accounts for 60-80% of the minimum fuel selling price across bio-based pathways. Fatty acid chain-length profiles directly determine hydrocarbon yield and jet-fraction selectivity in HEFA. Lignocellulosic heterogeneity is the principal technical bottleneck in gasification-FT routes. PtL pathways decouple production from biological feedstock constraints by substituting renewable electricity cost and CO$_2$ source quality as the governing variables.

The mining industry plays a substantial role in driving the increase of greenhouse gas (GHG) emissions in Indonesia, particularly through deforestation and the intensive use of fossil fuels. Consequently, evaluating GHG emissions from mining companies is essential for determining appropriate mitigation strategies. This study aims to assess the greenhouse gas emission profile within the coal mining service operations of PT Antareja Mahada Makmur. The assessment provides important insights into the environmental footprint of coal mining activities, which serve as a basis for guiding sustainable operational practices and ensuring compliance with environmental regulations. The findings indicate a notable escalation in total emissions from both mobile sources over the period from January 2025 to December 2025. Carbon dioxide (CO?) was identified as the predominant greenhouse gas emitted, especially from mobile equipment operations. These results underscore the urgency of implementing targeted mitigation measures, including enhancing energy efficiency and integrating renewable energy alternatives, to reduce the sector’s overall emission levels. Furthermore, this research offers valuable contributions in identifying emission-related challenges and proposing improvements that support corporate efforts toward achieving GHG reduction targets.

Traditional spent LiFePO4 (SLFP) recycling faces challenges such as high energy consumption, environmental pollution, and low profitability. A novel direct cascaded utilization strategy was proposed for SLFP, where phase fraction modulation in the SLFP lattice enabled efficient lithium extraction from secondary-treated lithium-containing brine. The approach precisely controlled LiFePO4 phase (x in LixFePO4) by regulating the oxidant dosage within a pH-maintained reversible phase transition framework. Moreover, the contraction of the crystal structure and the amplified disparity in Li+/Na+ diffusion energy barriers synergistically improve structure stability and ion selectivity. The Li+/Na+ diffusion energy barrier difference was up to 0.56 eV. During the (de)intercalation process, Li0.19FePO4 exhibited excellent structure stability and Li/Na separation capability. The dissolution loss rates of Fe and P atoms were only 0.27% and 0.58%. And the maximum Li+ recovery rate can reach 99% within 40 min. Furthermore, the economic and environmental analysis indicated that the new strategy yields 528% higher profit ($7.23 per kg of SLFP), 40.5% reduction in energy demand and 67.8% reduction in greenhouse gas (GHG) emissions compared to conventional pyrometallurgy. It bypasses the need for pre-sorting SLFP, enhancing SLFP recycling efficiency and promoting high-value use of lithium-containing brine through "urban mining".

An unprecedented increase in the number and the size of yellow mealworm beetle (Tenebrio molitor) farms in North America and Europe has been driven, among other factors, by the demand for sustainable proteins. Insect farming offers ecologic advantages, including lower land and water use and reduced greenhouse gas emissions. As in conventional livestock farming, veterinarians are essential to maintain insect health because disease outbreaks can reduce productivity, compromise animal welfare, and cause monetary loss. Yet, the role of veterinary diagnosticians remains limited in this emerging sector because of the lack of standardized diagnostic tools and anatomic references. The autopsy of an invertebrate is a valuable tool that can, just as in any other species, serve to determine the cause of death, identify underlying disease processes, and guide herd health management. However, performing beetle autopsies is technically challenging given their small size, rigid exoskeleton, and fragile internal organs. Here, we offer an illustrated, step-by-step dissection protocol for adult T. molitor using standard laboratory equipment. Our method emphasizes an aqueous immersion approach that preserves tissue integrity, enhances visibility, and yields consistent results. We describe the abdominal anatomy of both sexes, including the digestive, reproductive, and nervous systems. Structures include 6 testicular follicles, bean-shaped accessory glands, and a spermathecal gland in females that exceeds the spermatheca in size. The abdominal nerve cord comprises 7 metameric ganglia, with caudal fusion.

Maize–Soybean Intercropping and Organic Amendments as Sustainable Farming for Higher Productivity, Carbon Sequestration, and Greenhouse Gas Reduction

Global agriculture generates more than 5 billion tonnes of post-harvest crop residues each year, most of which remain unused for energy production. Within the broader landscape of advanced biomass and waste conversion technologies (thermochemical and biochemical pathways), producing biomethane from agricultural residues represents a complementary waste-to-energy route that converts decentralized feedstock into a standardized energy carrier. Mobilizing this agro-biomass for biogas/biomethane production via the anaerobic digestion of crop residues offers a promising instrument for decarbonizing agriculture, reducing greenhouse gas emissions, and advancing a circular bioeconomy. This study provides a techno-economic, environmental, and market assessment of biomethane production from post-harvest residues—specifically wheat and barley straw and maize stover—in Ukraine. We estimate the feedstock potential of crop residues and substantiate environmentally permissible removal levels accounting for soil organic matter requirements; we also characterize the role of digestate and biochar amendments in improving soil fertility, increasing mineral nitrogen availability, and enhancing crop yields. The results indicate substantial greenhouse gas mitigation potential relative to fossil natural gas. Practical recommendations are proposed to scale biomethane production from crop residues as part of Ukraine’s agricultural sustainability strategy. Under current cost and policy assumptions, many biomethane projects in Ukraine approach commercial viability, particularly in regions where damaged gas infrastructure creates local demand for a decentralized gas supply. The paper evaluates market assessment and investment feasibility of crop-residue biomethane scenarios under cost, regulatory, and infrastructure constraints. Overall, the findings suggest that agricultural residues can serve as a key feedstock for decarbonizing agriculture and biomethane-based energy systems in Ukraine.