Significant Emission Reductions Research Articles

Evaluating the effectiveness of cost-minimal planning of decarbonized electricity systems in reducing life cycle greenhouse gas emissions

Abstract The decarbonization of regional electricity systems is a critical enabler of broader economy-wide decarbonization strategies and has motivated robust research on how to decarbonize electricity systems at minimum monetary cost. Since these efforts often focus on the operation of electricity systems, however, they do not account for emissions of the full life cycle associated with different resources. Different resource mixes can achieve a similar level of decarbonization apparent decarbonization through operational emissions, while achieving very different levels of life cycle greenhouse gas (GHG) emissions reductions. To explore these differences, we model the expansion of the California electricity system from 2030 to 2045 using a simplified electricity dispatch model to investigate how the planning of future electricity systems may differ between prioritizing minimum cost versus minimum life cycle GHG emissions under a common target for operational GHG reductions. We find that explicitly planning for minimum life cycle GHG emissions yields an additional 1.6-2.0% reduction in annual life cycle GHG emissions at a cost penalty of 3.2–9.6% and that electricity resource mixes that minimize life cycle GHG emissions tend to favor high capacity factor zero-carbon resources and long-duration storage compared to a minimum cost approach. Comparatively, we find that aggressive supply chain decarbonization of generation and storage technologies reduces life cycle GHG emissions of electricity supplies by 3.0% to 14% and combining both increases these reductions to 5.0% to 16%. Further, we find that applying a carbon tax to minimum cost-based capacity expansion can incentivize planning to account for life cycle GHG emissions. Our results indicate that a planning approach focused on minimizing life cycle GHG emissions may not be palatable, but significant reductions in life cycle emissions can be realized through conventional mechanisms like carbon taxes, import standards, and targeted supply chain decarbonization.

Synthesis and characterization of advanced Ad-UiO-66@NGO composite for efficient CO2 capture and CO2/N2 adsorption selectivity.

Highly effective adsorbents, with their impressive adsorption capacity and outstanding selectivity, play a pivotal role in technologies such as carbon capture and utilization in industrial flue gas applications, leading to significant reductions in greenhouse gas emissions. This study aims to synthesize advanced composites via solvothermal methods, incorporating a defective Zirconium-based MOF and amine-functionalized graphene oxide. The main objective is to enhance the CO2 adsorption capacity of the composite and improve its CO2/N2 separation selectivity. The samples were characterized using XRD, FT-IR, TGA, FE-SEM, and nitrogen adsorption and desorption analysis. The composites' gas uptake capacity toward pure CO2 and N2 adsorption were tested at various temperatures and pressure ranges of 1-9 bar. The resulting amino-defective UiO-66/NGO composite containing 15 wt.% of amine-modified GO, displayed the highest CO2 uptake capacity of 15.13 mmol/g at 298 K and 9 bar, representing a remarkable 48% increase compared to the pristine MOF. Furthermore, isotherm and kinetic modeling showed a high level of agreement between the experimental data and the Freundlich and Elovich models, as indicated by their R2 values of 0.998 and 0.973, respectively. Moreover, the thermodynamic evaluation confirmed the exothermic and the spontaneity of the reaction. Furthermore, the adsorbent's CO2/N2 selectivity was evaluated using the ideal adsorbed solution theory, revealing a remarkable selectivity value of 148. The regenerability evaluation through cyclic adsorption experiments showed that the optimized composite maintained CO2 adsorption reversibility at over 81.50% after 55 adsorption-desorption cycles.

Variation of biogenic VOC contribution to ozone formation with reduced anthropogenic precursor emissions: Coupling online observation and future scenario simulation.

As an essential component of urban natural sources, isoprene has strong interactions and synergies with anthropogenic precursors (volatile organic compounds and nitrogen oxides) of ozone (O3), influencing O3 formation in urban areas. However, the variability of these effects under different anthropogenic emission scenarios has not been fully understood. This study, utilizing observational data from Dezhou (a medium-sized city in the center of North China Plain) from May to September in both 2019 and 2020, and incorporating four future scenarios based on Shared Socioeconomic Pathways (SSP1-2.6, SSP2-4.5, SSP3-7.0, SSP5-8.5), unravels the mechanisms of O3 formation and the impact of isoprene on O3 production using an observation-based box model. Our observation results showed that O3 concentrations were lower in 2020 compared to 2019. The box model analysis suggests a shift in O3 formation from a VOC-limited regime in 2019 to a transition regime in 2020, primarily due to a significant reduction in anthropogenic emissions. Isoprene photochemistry contributed to 7% and 11% of the daytime average net O3 production rates in 2019 and 2020, respectively. The increase can be attributed to a notable rise in RO2 radicals, from 14% in 2019 to 19% in 2020. Under the future scenario with the lowest projected anthropogenic emissions (SSP1-2.6), isoprene-derived RO2 radicals (generated through isoprene oxidation) are expected to account for 36% of the total RO2 radicals. We also use a quasi-EKMA diagram to illustrate the contribution of isoprene to O3 concentrations, highlighting the nonlinear amplification or reduction of its contribution depending on changes in anthropogenic VOCs and NOx concentrations. This nonlinear relationship is influenced by NOx concentrations, with the impact of isoprene being reduced at lower NOx levels. To effectively mitigate long-term O3 pollution, especially given the growing contribution of biogenic precursors, it is crucial to focus on reducing NOx emissions.

Green energy systems for powering electric vehicles considering telecommunication system with case study of Pakistan

The objective is to analyze the sustainability and efficiency of Pakistan’s telecommunication sector by developing a framework for base transceiver stations integrating renewable energy and charging stations. Various renewable energy sources such as solar, wind, biomass and hydropower were considered as the object of research. The following methodological steps were implemented in this work: site analysis; determination of optimal sizing of plants, energy storage systems and electric vehicle charging stations; cost-benefit analysis methods; greenhouse gas emissions estimation; and system design methods for integrating selected renewable energy sources and energy storage solutions, taking into account the operational requirements of the base transceiver stations. It is found that switching to hybrid renewable energy systems can significantly reduce dependence on diesel generators. It is shown that operating costs can be reduced by more than 80% compared to conventional diesel-fueled systems. Also, the introduction of hybrid renewable energy sources can lead to significant reductions in CO2 emissions. The integration of battery storage systems has been shown to improve the reliability of energy supply by ensuring uninterrupted operation during periods of high demand and blackouts. The proposed structure scheme for base transceiver stations is designed to accommodate future growth in the share of electric vehicles and technological advancements in renewable energy and electric vehicle charging. By prioritizing the integration of renewable technologies along with charging station infrastructure, telecom service providers in Pakistan can reduce their carbon footprint and operational costs. This approach not only addresses the unpredictability of the electricity grid, especially in rural areas, but also positions the telecoms sector as an active participant in global efforts to combat climate change.

Assessing a Hybrid Wind-Solar Irrigation System for Kiwi Orchards in Northern Iran: Feasibility, Environmental Impact, and Economic Viability

In this research, the viability of hybrid wind and solar energy for irrigating kiwi orchards in Guilan province, located in the northern part of Iran is explored. Analysis of wind speed data reveals that wind energy can be utilized for irrigation purposes for more than six months annually. The wind power density, peaking at 467 W/m², supports the feasibility of wind energy for irrigation over ten months each year. Solar irradiance measurements estimate an energy generation of approximately 5.23 kWh/m² from January to July. The average daily temperature, peaking at 29.7°C, suggests optimal conditions for the efficient operation of solar panels. The net water requirement for the kiwi orchard during the irrigation period was calculated based on garden area and other relevant parameters, ensuring accurate irrigation planning. Using the calculated net water requirements and meteorological data, the necessary pumping power was determined, leading to the design of a hybrid wind-solar irrigation system. An environmental impact assessment estimated a significant reduction in CO2 emissions over a 25-year period. Additionally, a life-cycle cost analysis demonstrated that the hybrid irrigation system would incur only 60% of the total cost of a conventional system over the same period, highlighting its economic feasibility.

EXAMINING THE ECO-FRIENDLY ASPECTS OF ETHANOL–METHANOL BLENDED GASOLINE ON ENGINE PERFORMANCE AND EMISSIONS

The increasing global demand for energy, environmental concerns, and the limited availability of energy resources have heightened interest in alternative fuels for internal combustion engines. In this context, internal combustion engines like gasoline engines play a significant role in the search for environmentally friendly and sustainable energy sources. Alcohols are among the most used alternative fuels in spark-ignition engines. This study examines the feasibility of using ethanol and methanol alcohols as fuels simultaneously in a gasoline engine. The research investigates the effects of blending 10% ethanol and 10% methanol alternative fuels with gasoline and using the resulting blended fuel as the engine's fuel source on motor performance and exhaust emissions. The study was conducted under throttle wide-open conditions at different engine speeds. The results revealed a maximum decrease of 1.3% in effective power. Significant reductions in hydrocarbon and nitrogen oxide emissions were observed at all engine speeds, with maximum reductions of 18% and 19%, respectively. Furthermore, a decrease in carbon monoxide emissions is evident across the entire spectrum of engine speeds, underscoring the potential of ethanol-methanol blended gasoline to contribute to a reduced carbon footprint in the transportation sector. As a result of the study, in the case of using ethanol and methanol in engines, both the higher oxygen content of alcohols and their high evaporation energy due to their cooling effect cause an improvement in the emission values emitted from the engine without significant deterioration in engine performance parameters.

The Impact of Digitalization on Manufacturing Firms’ Competitiveness, Environmental Sustainability, and Social Inclusiveness

Manufacturing is a crucial driver of economic growth, contributing approximately 17% to global GDP. This research investigates the impact of digitalization on manufacturing firms' competitiveness, environmental sustainability, and social inclusiveness, using Canon Inc.’s operations globally as a case study. Existing literature underscores the transformative potential of digital economics in the manufacturing industry; however, a comprehensive exploration of its impact on sustainability remains to be explored in detail. Employing a mixed-methods approach and Systems Theory as a theoretical framework, data was gathered from Canon's sustainability reports, financial statements, and online sources, focusing on the years 1997 to 2018. The study analyzes the implementation of digital technologies and their effects on profitability and sustainability outcomes. The research results indicate positive results with sustainable firms able to beat the competition in the long-run, as demonstrated by Canon’s revenue of approximately $36 billion in 2018 alongside significant reductions in CO2 emissions by 435,000 tonnes and a reduction in raw material usage by 314,000 tonnes. Additionally, Canon’s social initiatives, such as the Miraisha Programme, underscore its commitment to inclusivity. This study highlights the multifaceted benefits of integrating digital technologies in manufacturing, offering insights for firms aiming to balance profitability with sustainability.

Carbon Tax Policy, Stranded Assets and "Double Pillar" Regulation

The risk of a transition from climate policy has drawn widespread attention from central banks. By constructing a new Keynes dynamic stochastic general equilibrium model (NK-DSGE) including climate policy, asset quality and "two-pillar" policy, this paper studies the possible transition risk caused by carbon tax policy and analyzes the transition risk from the perspective of stranded assets. On this basis, the effect of the "dual-pillar" policy to deal with the transformation risk is further evaluated and the optimal policy combination is found through the comparative analysis of social welfare. Research shows that:(1)carbon tax policy has a significant emission reduction effect, but it may cause "stagflation" and lead to the "grounding" of carbon-intensive assets, causing a certain risk of transformation.(2)When the central bank deals with the risk of transformation, it should not only focus on the inflation target. At the same time, we should actively stimulate output, promote the development of the low-carbon sector, solve the mismatch between energy supply and demand, and address the root cause of inflation. When the central bank operates the price monetary policy, the central bank can reduce the risk of transformation and improve the operation efficiency through interest rate smoothing.(3)The macro-prudential policy of "brown punishment" can effectively alleviate the risk of transformation and improve social welfare. The macro-prudential policy of "green support" will not only promote the economic recovery, but also lead to the rising leverage ratio of banks in the short term, aggravating the financial risks faced by banks and causing the loss of social welfare.(4)An effective "two-pillar" policy mix is better to the single use of monetary policy tools in mitigating transition risks and improving social welfare.

Effects of nozzle geometry, compression ratio and cerium oxide nanoparticles on algae biodiesel performance in a VCR diesel engine with hydrogen addition

This paper discusses an exploratory analysis of performance and emissions characteristics of a variable compression ratio (VCR) diesel engine using various compression ratios, nozzle hole configurations, and injection timings. Results will be employed to further elucidate interactions among those parameters as well as their influence upon the operation efficiency and environmental output. An engine was tested on the B20 biodiesel blend from the transesterification of algal oil. The sample, which contained nano-additives with cerium oxide (CeO2) at a concentration of 75 ppm, underwent extensive analysis using scanning electron microscopy and energy dispersive X-ray analysis (FTIR). The study included different compression ratios such as 16:1, 17:1, 18:1, and 19:1, utilizing nozzle designs with hole diameters of 2, 3, 4, and 5 mm. Additionally, it also examines the effects of hydrogen injection at time intervals of 3, 4, and 5 ms, aiming to comprehend the interaction between these parameters and their impact on the performance outcome. The presence of CeO2 75 ppm resulted in a significant reduction in emissions, as well as improved combustion efficiency. The configuration resulted in a 6.1% improvement in brake thermal efficiency (BTE), as well as a decrease in brake specific fuel consumption (BSFC) from 250 g/kWh to 200 g/kWh. Improving the number of holes in the nozzle revealed a drop in the temperature of the exhaust gas up to 250°C. Reduced nitrogen oxide (NOX) emissions and improved cylinder pressure accompanied these decreases, thanks to the increased heat release rates generated by hydrogen addition. The addition of CeO2 nanoparticles to the B20 blended fuel, along with modifications to the nozzle hole design and hydrogen injection, not only reduces emission values but also lowers fuel consumption, lowers exhaust gas temperature (EGT), and improves combustion efficiency.

The Electrification of Transport: Key Drivers, Challenges, and Future Directions

The electrification of transport is increasingly recognized as a pivotal strategy in global efforts to mitigate climate change, reduce greenhouse gas (GHG) emissions, and decrease dependency on fossil fuels. This paper investigates the key drivers behind the shift toward electric transportation, emphasizing environmental benefits, energy security, and technological advancements. Notable environmental advantages include significant reductions in CO2 emissions and air pollution, while energy security is enhanced by diminished reliance on oil and improved integration of electric vehicles (EVs) with renewable energy sources. Technological progress in battery systems, electric drivetrains, and smart grid infrastructure has accelerated the feasibility of widespread EV adoption. Despite these advances, the transition to electric transport faces several challenges, including the need for extensive charging infrastructure, sustainable sourcing of critical materials like lithium and cobalt, and the economic impacts on industries and labor markets. The paper explores strategies to overcome these challenges, such as advancements in recycling technologies, enhanced grid management, and supportive economic policies. By analyzing both the drivers and barriers, this paper provides a comprehensive assessment of the current landscape and future prospects for sustainable transport electrification.

The Promotion of Anaerobic Digestion Technology Upgrades in Waste Stream Treatment Plants for Circular Economy in the Context of “Dual Carbon”: Global Status, Development Trend, and Future Challenges

This review provides a comprehensive overview of the advancements and challenges of anaerobic digestion technology in waste stream treatment plants under the framework of the circular economy, emphasizing its role in achieving “dual carbon” goals. As climate change intensifies, with waste stream treatment contributing significantly to global emissions, there is a pressing need to optimize energy efficiency and reduce carbon outputs in this sector. Anaerobic digestion is highlighted as a solution for converting organic waste into renewable biogas and digestate, enabling energy self-sufficiency and reducing greenhouse gasses. The study highlights that anaerobic digestion enables the conversion of organic waste into renewable biogas and nutrient-rich digestate, facilitating energy self-sufficiency and significant reductions in GHG emissions. Successful implementations, such as in Weifang, China, demonstrate the feasibility of upgrading biogas into biomethane for local energy use. Advanced technologies like bioelectrochemical methanation and membrane bioreactors enhance biogas production efficiency, while co-digestion proves effective even in challenging conditions. Despite these advancements, the review identifies critical challenges, including high investment costs, technical inefficiencies, and regulatory barriers, particularly in developing countries. This study provides insights into integrating anaerobic digestion with circular economy principles and offers a foundation for future policies and research aimed at achieving carbon neutrality and sustainable waste management.

Multi-Objective Economic Dispatch Problems: An Evolutionary Programming Approach

Optimizing multiple objectives is a common challenge in complex decision-making scenarios, where improving one objective often comes at the expense of another. In power system generation, two critical objectives must be simultaneously minimized: the total generation cost and the total emissions released. This study introduces a multi-objective optimization method developed to address these dual objectives. The proposed approach aims to identify the optimal solution to the economic dispatch problem, balancing the trade-off between minimizing generation costs and reducing environmental impact by lowering total emissions. Heuristic optimization is used to solve this multi-objective combined economic and emission dispatch (MOCEED) problems through the implementation of Multi-Objective Evolutionary Programming (MOEP). In this study, the Weighted Sum Method (WSM) is combined with the Evolutionary Programming (EP) technique to minimize both objectives. The developed approach is validated on the IEEE 30-Bus RTS, which consists of six generators. The effectiveness of the developed technique is evaluated and compared the results against scenarios without optimization. Simulations are performed using MATLAB software, and the results demonstrate that the proposed Multi-Objective Evolutionary Programming (MOEP) successfully identifies the optimal generator outputs, achieving significant reductions in both total generation cost and emissions. These results highlight the method's capability to provide superior solutions for multi-objective economic dispatch problems.

Exploring the cost–carbon trade‐off in using a mixed fleet of hydrogen trucks and diesel trucks

AbstractHydrogen trucks (HTs) offer promising potential for decarbonizing the transportation sector. Based on current technologies, they have significant advantages over electric trucks (ETs) in terms of range, refueling time, and performance in cold conditions. However, HTs are costly, and there are insufficient hydrogen refueling stations (HRSs). Gradually integrating HTs into the existing diesel truck (DT) fleet is a practical approach for many freight logistics companies. In this article, we formulate a mathematical model to route a mixed fleet of HTs and DTs, and we propose an algorithm called the curve descent search (CDS) to generate the Pareto set based on cost and carbon emissions. We find that CDS can generate better Pareto sets compared to existing algorithms in the literature. We use CDS to comprehensively explore the cost–carbon trade‐off in using a mixed fleet. This question differentiates our study from previous research and is motivated by discussions with one of the largest third‐party logistics companies in North America. Detailed experiments reveal important managerial insights, such as: (1) Achieving a significant reduction in carbon emissions (e.g., a 30% reduction compared to the current diesel fleet) does not need a very dense refueling infrastructure; (2) The cost–carbon trade‐off for mixed fleets is relatively insensitive to variations in customer density and demand, suggesting that HTs can be applicable across a wide range of scenarios (including different sectors or regions); and (3) Although ETs are cheaper to use compared to HTs, their shorter range limits their competitiveness in terms of decarbonization efficiency and customer service.

The Role of Hydrogen in the Energy Mix: A Scenario Analysis for Turkey Using OSeMOSYS

The urgent need to tackle climate change drives the research on new technologies to help the transition of energy systems. Hydrogen is under significant consideration by many countries as a means to reach zero-carbon goals. Turkey has also started to develop hydrogen projects. In this study, the role of hydrogen in Turkey’s energy system is assessed through energy modeling using the cost optimization analytical tool, Open Source Energy Modelling System (OSeMOSYS). The potential effects of hydrogen blending into the natural gas network in the Turkish energy system have been displayed by scenario development. The hydrogen is produced via electrolysis using renewable electricity. As a result, by using hydrogen, a significant reduction in carbon dioxide emissions was observed; however, the accumulated capital investment value increased. Furthermore, it was shown that hydrogen has the potential to reduce Turkey’s energy import dependency by decreasing natural gas demand.

CARBONLY

This project focuses on the development and implementation of a Carbon Footprint App designed to empower individuals and organizations to track and reduce their carbon emissions. By providing real-time tracking, personalized recommendations, and engaging features such as gamification and community challenges, the app aims to foster sustainable practices and raise awareness about the environmental impact of everyday activities. The methodology involves collecting user data on energy use, transportation, food consumption, and waste management, converting this data into carbon dioxide equivalents, and offering actionable advice to lower emissions. The app is applicable across various sectors, including personal use, corporate sustainability, policy support, education, supply chain management, urban planning, and environmental certification. The results demonstrate that informed individual actions, such as skipping a weekly cup of coffee or reducing chocolate consumption, can collectively lead to significant reductions in carbon emissions. This project underscores the importance of individual responsibility in combating climate change and promotes a community-driven approach to achieving a more sustainable future. Key Words: Carbon Footprint, Real-time Tracking, Gamification, Personalized Recommendations, Sustainability

Study of the Biogas Ebullition from Lacustrine Carbonate Enriched and Black Silt Bottom Sediments

The greenhouse effect, which is also promoted by naturally occurring biogas ebullition fluxes (released via bubbles), generated by the decomposition of organic matter in carbonate-enriched and black silt sediments, has been analyzed. This study is based on results obtained using passive gas collectors at different parts of eutrophic Lake Juodis, located in a temperate climate zone in the vicinity of Vilnius (Lithuania). The measured annual biogas (containing about 60% of biomethane) ebullition fluxes from carbonate-enriched sediments and black silt sediments were 16.9–23.0 L/(m2∙y) and 38.5–43.2 L/(m2∙y), respectively. This indicates that the gas fluxes from carbonate sediments were almost twice as low as those from black silt sediments. Oxygen, produced by the photosynthetic activity of green algae in the near-surface water and sediments, helps to retain carbonates in the sediments by preventing their dissolution. In turn, the calcite coating on sediment particles partially preserves organic matter from decomposition, reducing the effective thickness of the sediment layer generating biogas. The characteristic vertical distribution profile of 137Cs activity, with sharp peaks in sediments, suggests that generated biogas bubbles move to the surface of the sediments forming vertical channels by pushing sediment particles asides without noticeably mixing them vertically. This examination showed that factors such as abundance of carbonates in the sediments may result in a significant reduction in biogas generation and emissions from the lake sediments.

Geothermal Condition Investigation and Resource Potential Evaluation of Shallow Geothermal Energy in the Yinchuan Area, Ningxia, China

Shallow geothermal energy (SGE) is a promising green and sustainable energy source, gaining prominence in light of the dual-carbon target. This study investigated the SGE resources in the Yinchuan area. Suitability zones and the potential of SGE resources were determined based on the comprehensive analysis about thermophysical parameters, hydrogeological conditions, and geological environment. Our findings revealed that the effective thermal conductivity in the Yinchuan area surpasses those of other cities, indicating significant potential for SGE. The thermostat layer depth ranges from 40 to 60 m, with a geothermal gradient between 0.81 and 6.19 °C/100 m. Regions with poor adaptability for a borehole heat exchanger (BHE) are mainly distributed in the western and southern parts of the Yinchuan area, whereas moderately and highly adaptable areas are primarily located in the central and eastern areas, respectively. The total geothermal resource of the BHE in the Yinchuan area amounts to 1.07 × 108 GJ/a, generating significant economic benefits of 1.07 × 109 CNY/a and saving 1.09 × 106 t/a of standard coal annually. This initiative leads to significant reductions in CO2, SO2, and NOx emissions by 2.61 × 106 t/a, 1.86 × 104 t/a, and 6.57 × 103 t/a, respectively. Additionally, it results in potential savings of 0.309 × 109 CNY/a in environmental treatment costs. The methods and models used in this study have potential for similar geothermal surveys in arid and cold regions. The results also contribute essential insights for policy formulation and sustainable development strategies related to shallow geothermal resources in the Yinchuan area.

Innovative Approaches to Bridging Energy Supply and Demand Gaps Through Thermal Energy Storage: A Case Study

This study investigates innovative solutions for balancing energy supply and demand using long-term thermal energy storage (TES) systems, with a focus on tank thermal energy storage (TTES) for European buildings, which account for approximately 40% of energy consumption in the European Union. Research conducted at the Technical University of Košice explores the potential of TTES systems for efficient and long-term energy storage. The accumulation is carried out in three existing underground tanks of different volumes. Among various outputs, we present the cooling process resulting from covering the water surface and the effect of tank size on cooling. The findings indicate that covering the water surface in the tanks can effectively double the energy retention time, thereby extending the cooling period. A tank with a larger volume cools slower and better ensures the formation of temperature layers. Temperature layering allows for better utilization of the tanks’ potential in terms of energy. The overall result is a significant reduction in heat losses and CO₂ emissions. These results demonstrate the critical role of TTES in stabilizing renewable energy sources, especially solar energy, to support sustainable energy solutions in buildings by providing reliable and long-term energy storage.

The Use of Mesquite Pods (Prosopis spp.) as an Alternative to Improve the Productive Performance and Methane Mitigation in Small Ruminants: A Meta-Analysis

Mesquite (Prosopis spp.), a highly nutritious legume from arid regions characterized by its secondary metabolites, offers a cost-effective resource to provide energy and protein for small ruminant farmers in harsh environments. In addition, the high concentrations of secondary metabolites found in mesquite pods could be an option to mitigate methane (CH4) emissions. Thus, the aim of this study was to conduct an analytical review to assess the impact of adding mesquite pods on small ruminant productivity and enteric CH4 emissions. A comprehensive and structured search of scientific articles resulted in a database of 38 trials. The response variables were evaluated through raw mean differences (RMDs) and standardized mean differences (SMDs), followed by a meta-regression, used to investigate the heterogeneity of the explanatory variables. Supplementation with mesquite pods significantly increased the dry matter intake (DMI) and average daily gain (ADG) and reduced the feed conversion ratio (FCR), with sheep showing the highest effect. The meta-regression demonstrated that the mesquite pod effect was influenced mainly by the species, level of incorporation and processing of the pods. Studies employing in silico CH4 estimation reported increased emissions when the diets included mesquite pods. In contrast, in vivo studies demonstrated promising results, showing a significant reduction in CH4 emissions when mesquite pods were included in small ruminant diets. Therefore, future research should focus on evaluating mesquite pod supplementation using precise methods to assess CH4 emissions.

Research on Low-Carbon Site Selection Decision Model and Algorithm for Green Logistics

This work proposes a low-carbon site selection decision model and algorithm for green logistics. The focus is to minimize carbon emissions while optimizing the distribution network. With the development of smart shared logistics and increasing environmental awareness, there is an urgent need to tackle issues in urban logistics, including pollution, resource inefficiency, high carbon energy usage, and greenhouse gas emissions. By integrating geographic, environmental, and operational data, the proposed site selection model incorporates multi-objective optimization to balance carbon efficiency with cost-effectiveness in logistics site selection. We employ a hybrid algorithm combining Genetic Algorithm (GA) and Particle Swarm Optimization (PSO) to solve the complex decision-making process. The model is tested using real-world logistics data, and the results demonstrate significant reductions in carbon emissions and transportation costs when compared to conventional logistics site selection methods. Further sensitivity analysis reveals that the model is robust under varying transportation demands and geographic constraints. Also, we highlight the role of green logistics in achieving corporate sustainability goals aligning with global carbon neutrality initiatives. We believe this model offers a practical approach to fostering environmentally responsible supply chains and will contribute to the advancement of sustainable logistics operations, helping organizations make informed, eco-friendly decisions in site selection.