Search Results (2,717)

Amid escalating climate challenges, China’s carbon neutrality objectives necessitate energy electrification as a pivotal strategy. As a critical load hub, East China demonstrates significant trends toward cleaner energy—marked by growing renewable energy penetration and accelerated cross-regional direct current (DC) transmission deployment. Ensuring stable and efficient grid operation requires rigorous assessment of the impacts of ultra-high voltage DC (UHVDC) integration on grid stability. This study introduces the transient multi-feed-in short circuit ratio (TMSCR), a novel metric for evaluating new DC transmission systems’ influence on grid performance. We systematically investigate UHVDC integration within the East China power grid, emphasizing strategic DC landing point placement. Using TMSCR, the effects of diverse DC incorporation methods are analyzed. Furthermore, this research examines impacts of new DC connections on local and main grids, proposing targeted mitigation measures to enhance grid resilience. This comprehensive UHVDC impact analysis addresses a critical literature gap, providing actionable insights for East China power grid planning and establishing a foundation for subsequent grid planning and DC project feasibility studies during the ‘15th Five-Year Plan’ period. Full article

Energy security has emerged as a critical concern amid intensifying climate risks and surging energy demand driven by economic growth. This study examines the impact of climate risk on energy security by constructing a panel dataset covering 30 Chinese provinces from 2006 to 2022. Using the instrumental variable generalized method of moments (IV-GMM) model, we estimate the marginal impact of climate risk on energy security and further investigate its asymmetric, direct, and indirect relationships via panel quantile regression and mediation analysis. Our key findings are as follows: (1) Climate risk exerts a significant negative impact on energy security, indicating an inverse relationship. (2) The effect of climate risk is asymmetric, with a stronger adverse impact in regions with lower levels of energy security. (3) Climate risk undermines energy security by reducing energy accessibility, affordability, sustainability, and technological efficiency. (4) Energy transition and energy efficiency serve as critical mediators in the relationship between climate risk and energy security, offering insights into potential mitigation pathways. Unlike previous studies that primarily examine energy security in isolation or focus on single dimensions, this research integrates a multidimensional indicator system and advanced econometric techniques to uncover both direct and mediated pathways, thereby filling a key gap in understanding the climate–energy nexus at the provincial level in China. Based on these findings, we propose targeted policy recommendations to enhance energy security by improving climate resilience, accelerating the deployment of renewable energy, and optimizing energy infrastructure investments. Full article

Decarbonizing air transport is a major challenge in the global energy transition since electrification is not yet feasible. Sustainable aviation fuel (SAF) is a promising solution because it can reduce CO₂ emissions without major infrastructure changes. This study proposes a decentralized model for producing SAF in Spain through the gasification of residual lignocellulosic biomass followed by a refinement process using Fischer–Tropsch (FT) synthesis. The model uses underexploited agricultural residues such as cereal straw, vine pruning, and olive pruning, converting them into syngas in medium-scale facilities situated near biomass sources. The syngas is then transported to a central upgrading unit to produce SAF compliant with ASTM D7566 standards. The following two configurations were evaluated: one with a single gasification plant and upgrading unit and another with three gasification plants supplying one central FT facility. Energy yields, capital and operational expenditures (CAPEX and OPEX), logistic costs, and the levelized cost of fuel (LCOF) were assessed. Under a conservative scenario using one-third of the available certain types of biomass from three regions of Spain, annual SAF production could reach 517.6 million liters, with unit costs ranging from 1.63 to 1.24 EUR/L and up to 47,060 tonnes of CO₂ emissions avoided per year. The findings support the model’s technical and economic viability and its alignment with circular economy principles and climate policy goals. This approach offers a scalable and replicable pathway for decarbonizing the aviation sector using local renewable resources. Full article

This study evaluates the viability of a specific hybrid renewable energy system (HRES) installation designed for a remote community as a case study in Cuba. The system integrates solar, wind, and biomass resources to address localised challenges of energy insecurity and environmental degradation. Rather than offering a generalised evaluation of HRES technologies, this work focuses on the performance, impacts, and viability of this particular configuration within its unique geographical, social, and technical context. Using life cycle assessment (LCA) and input–output modelling, the research assesses environmental and socioeconomic impacts. The proposed HRES reduces greenhouse gas emissions by 60% (from 1.14 to 0.47 kg CO₂eq/kWh) and fossil energy consumption by 50% compared to diesel-based systems. Socioeconomic analysis reveals that the system generates 40.3 full-time equivalent (FTE) jobs, with significant employment opportunities in operation and maintenance. However, initial investments primarily benefit foreign suppliers due to Cuba’s reliance on imported components. The study highlights the potential for local economic gains through workforce training and domestic manufacturing of renewable energy technologies. These findings underscore the importance of integrating multiple renewable sources to enhance energy resilience and sustainability in Cuba. Policymakers should prioritise strategies to incentivise local production and capacity building to maximise long-term benefits. Future research should explore scalability across diverse regions and investigate policy frameworks to support widespread adoption of HRES. This study provides valuable insights for advancing sustainable energy solutions in Cuba and similar contexts globally. Full article

This study investigates the energy consumption characteristics of individual and clustered thermal storage electric heating systems, focusing on their sustainability implications for regional load distribution and user energy consumption patterns. Simulation results show that thermal storage electric heating shifts peak energy demand from daytime to nighttime low-price hours, reducing electricity costs and optimizing grid load balancing. As the proportion of thermal storage electric heating increases from 10% to 30%, the daytime minimum load reduction rate rises from 7% to 22%, while the nighttime maximum load increase rate increases from 16% to 63%. This operational mode supports sustainable energy usage by alleviating daytime grid peak pressure and leveraging low-cost, off-peak electricity for heat storage. The findings highlight the potential of thermal storage electric heating to enhance energy efficiency, integrate renewable energy, and promote grid stability, contributing to a more sustainable energy system. Full article

While technologies like renewable energy and low-carbon transportation are known to mitigate carbon emissions from urban expansion, achieving carbon neutrality during this process remains a critical unresolved challenge. This issue is particularly pressing for developing countries striving to balance urbanization with carbon reduction. Taking Qionglai City as a case study, this study simulated the territorial spatial functional patterns (TSFPs) and carbon emission distribution for 2025 and 2030. Based on the key drivers of carbon emissions from urban expansion identified through the Geographical and Temporal Weighted Regression (GTWR) model, carbon-neutral pathways were designed for two scenarios: urban expansion scenarios under historical evolution patterns (Scenario I) and urban expansion scenarios optimized under carbon neutrality targets (Scenario II). The results indicate that (1) urban space is projected to expand from 6094.73 hm² in 2020 to 6249.77 hm² in 2025 and 6385.75 hm² in 2030; (2) total carbon emissions are forecasted to reach 1.25 × 10⁶ t (metric tons) and 1.40 × 10⁶ t in 2025 and 2030, respectively, exhibiting a spatial pattern of “high in the central-eastern regions, low in the west”; (3) GDP, Net Primary Productivity (NPP), and the number of fuel vehicles are the dominant drivers of carbon emissions from urban expansion; and (4) a four-pronged strategy, optimizing urban green space vegetation types, replacing fuel vehicles with new energy vehicles, controlling carbon emissions per GDP, and purchasing carbon credits, proves effective. Scenario II presents the optimal pathway: carbon neutrality in the expansion zone can be achieved by 2025 using the first three measures (e.g., optimizing 66.73 hm² of green space, replacing 800 fuel vehicles, and maintaining emissions at 0.21 t/10⁴ CNY per GDP). By 2030, carbon neutrality can be achieved by implementing all four measures (e.g., optimizing 67.57 hm² of green space, replacing 1470 fuel vehicles, and achieving 0.15 t/10⁴ CNY per GDP). This study provides a methodological basis for local governments to promote low-carbon urban development and offers practical insights for developing nations to reconcile urban expansion with carbon neutrality goals. Full article

The increasing demand for renewable energy, coupled with the urgent challenges posed by climate change, has positioned perennial biomass crops (BPGs) as essential and sustainable alternatives for bioenergy production. This study investigated the impact of irrigation regimes on the physiological performance of three BPG species—Arundo donax L., Saccharum spontaneum, and Miscanthus—with a focus on leaf gas exchange (net assimilation rate and transpiration rate) and instantaneous water use efficiency (iWUE) at varying levels of irrigation input, adopting a split-plot experimental design under the Mediterranean climatic conditions of Sicily (Italy). The results clearly showed that A. donax, a C3 species, outperformed the C4 species S. spontaneum and Miscanthus, exhibiting significantly higher stomatal conductance and net photosynthesis, especially under irrigated conditions. S. spontaneum demonstrated the highest iWUE, particularly in rainfed treatments, reflecting its efficient use of water. Miscanthus showed the greatest sensitivity to water stress, with a more pronounced decline in photosynthesis during drought periods. This study accentuated the role of effective water management and genotype selection in optimizing biomass yield and resource efficiency, providing valuable insights for improving crop productivity in Mediterranean and other semi-arid regions. Full article

Background and Objectives: The cultivation of Humulus lupulus has been encouraged in Brazil, despite the country’s climate generally being unfavorable for its development. This study aimed to evaluate the chemical composition, antioxidant activity, and photoprotective potential of four H. lupulus varieties, Cascade, Columbus, Comet, and Nugget, cultivated in the northwestern region of Paraná State, Brazil. Methods: The varieties were grown in experimental plots. Crude extracts (CEs) of cones and leaves were obtained through dynamic maceration with solvent renewal (96% ethanol), followed by concentration in a rotary evaporator. Assays for sun protection factor (SPF), total phenolic content (TPC), total flavonoid content (TFC), ferric reducing antioxidant power (FRAP), 2.2-diphenyl-1-picrylhydrazyl (DPPH^•) radical scavenging activity, and 2.2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS^•⁺) were performed to assess antioxidant activity. Chemical profiling was performed using UHPLC-MS/MS. Results: UHPLC-MS/MS analysis revealed the presence of phenolic and organic acids, flavonoids, phenolic aldehydes, alkaloids, and α-benzopyrone-type lactones, with high concentrations of rutin (>500 µg/g) in both cones and leaves. Total phenolic content ranged from 69.70 to 95.95 µg gallic acid equivalent/mg CE; flavonoids from 170.53 to 696.67 µg quercetin equivalent/mg CE; DPPH^• EC₅₀ values ranged from 1.34 to 3.13 mg/mL; FRAP from 1.19 to 2.52 µM ferrous sulfate/mg; ABTS^•⁺ from 5.11 to 22.60 mM Trolox/mg CE; and SPF ranged from 16.02 to 39.48 in the CE of H. lupulus cones and leaves. Conclusions: These findings demonstrate that the cultivated varieties possess antioxidant and photoprotective properties, encouraging further studies to explore their potential applications. Full article

This study explores public perceptions, involvement, and barriers to energy communities in Romania, a country where decentralized renewable energy initiatives are still in their infancy. Data were collected through a nationwide online survey based on a quantitative research design, involving 118 respondents from all four macro-regions in Romania. The survey assessed awareness of the concept of energy communities, perceived benefits, technological and regulatory challenges, and willingness to participate or invest. The results show that the perception of energy communities is generally positive, with solar and environmental benefits being the most important. However, significant barriers remain, particularly in terms of financing, institutional support, and regulatory complexity. Urban, involved, and female respondents consistently rated benefits higher and identified more barriers than rural, non-participants and male respondents. Statistical differences between groups were confirmed using the Mann–Whitney U-test. These results highlight the importance of targeted communication, improved policy frameworks, and educational initiatives to ensure broader public involvement and inclusive development of renewable energy systems in Romania. Full article

Rapid urban growth poses distinct energy and environmental challenges in various regions of the world. This study evaluated the technical and economic feasibility of a grid-connected photovoltaic system in Santo Domingo Tehuantepec, Oaxaca, Mexico, using Homer Pro software, version 3.14.2, to simulate realistic scenarios. The analysis incorporated local climate data, residential load profiles, and updated economic parameters for 2024. System optimization resulted in an installed capacity of 173 kW of solar panels and 113 kW of inverters, yielding a levelized cost of energy (LCOE) of MXN 1.43/kWh, a return on investment (ROI) of 5.3%, an internal rate of return (IRR) of 8%, and a simple payback period of 10 years. The projected annual energy output was 281,175 kWh, covering 36% of the local energy demand. These results highlight the potential for integrating renewable energy into urban contexts, offering significant economic and environmental benefits. The integration of public policy with urban planning can enhance energy resilience and sustainability in intermediate cities. This study also supports the application of tools such as Homer Pro in designing energy solutions tailored to local conditions and contributes to a fair and decentralized energy transition. Full article

In the context of global warming and China’s “dual carbon” goals, Shanxi, as China’s main coal-producing region (accounting for 28.4% of the country’s coal production), is facing the dual challenges of carbon emission reduction and economic development. Based on the data from 1990 to 2019, this study quantitatively analysed the carbon emission driving mechanisms of seven major energy sources in Shanxi, including coal, coke, and gasoline, through the coupling analysis of the Kaya identity and the LMDI model, and explored the climate change mitigation pathways. The results show that the total carbon emissions of Shanxi’s energy sector increased significantly from 1990 to 2019, with coal being the most important emission source. Through the decomposition of the LMDI model, it is found that the effect of economic activity is the core driving force of carbon emission growth, and the improvement of energy intensity is the key inhibitor. It is worth noting that the demographic effect turned negative after 2010, which had a dampening effect on the growth of carbon emissions. In addition, the adjustment of energy structure shows the characteristics of stages: the structural effect of coal has turned from negative to positive after 2010, while the proportion of clean energy, such as natural gas, has increased, indicating that the optimisation of energy structure has achieved initial results. Based on the above findings, the study proposes three major paths for climate mitigation in Shanxi’s energy industry: (1) promote low-carbon upgrading of the industry and reduce the economy’s dependence on high-carbon energy; (2) Strengthen energy efficiency and continuously reduce energy consumption per unit of GDP through technological innovation; (3) accelerate the transformation of the energy structure and expand the proportion of clean energy such as natural gas and renewable energy. This paper innovatively provides an empirical reference for the model-based, coupling-based carbon emissions-driven analysis and climate mitigation strategy design in resource-based areas. Full article

This paper analyses the role of electronic waste (E-waste) as a secondary source of critical and precious minerals, addressing the challenges and opportunities in transitioning towards a circular economy (CE) for electronics. The surging global demand for these essential materials, driven by technological advancements and renewable energy infrastructure, necessitates alternative supply strategies due to the depletion of natural reserves and the environmental degradation associated with primary mining. E-waste contains a rich concentration of valuable metals, such as gold, silver, and platinum, making its recovery a promising solution aligned with CE principles, which can mitigate environmental impacts and ensure long-term material availability. This paper examines the environmental, economic, and technological aspects of E-waste recovery, focusing on core processes such as physical and mechanical separation, pyrometallurgical, hydrometallurgical, bio-metallurgical, and electrochemical techniques. It explores innovative strategies to improve material recovery efficiency and sustainability, with consideration of evolving regulatory frameworks, technological advancements, and stakeholder engagement. The analysis highlights that e-waste, particularly printed circuit boards, can contain 40–800 times more gold than mined ore, with 1000–3000 g of gold per tonne compared to 5–10 g per tonne in traditional ores. Recovery costs using advanced E-waste recycling technologies range between $10,000–$20,000 USD per kilogram of gold, significantly lower than the $30,000–$50,000 USD per kilogram in primary mining. Globally, over 50 million tonnes of E-waste are generated annually, yet less than 20% is formally recycled. Efficient recycling methods can recover up to 95% of base and precious metals under optimized conditions. The paper argues that E-waste recycling presents a viable pathway to conserve critical raw materials, reduce environmental degradation, and enhance circular economic resilience. However, it also emphasizes persistent challenges—including high initial investment, technological limitations in developing regions, and regulatory fragmentation—that must be addressed for scalable adoption. Full article

To address the increasing need for clean energy and efficient resource utilization, this paper aims to provide a cooperative framework and a fair profit allocation mechanism for integrated photovoltaic (PV) and energy storage systems that are shared among different types of users within a regional alliance, including industrial, commercial, and residential users. A cooperative game model is proposed and formulated by a two-level optimization problem: the upper level determines the optimal PV and storage capacities to maximize the alliance’s net profit, while the lower level allocates profits using an improved Nash bargaining approach based on Shapley value. The model simultaneously incorporates different real-world factors such as time-of-use electricity pricing, system life cycle cost, and load diversity. The results demonstrate that coordination between energy storage systems and PV systems can avoid 18% of solar curtailment losses. Compared to independent deployment by individual users, the cooperative sharing model increases the net present value by 8.41%, highlighting improvements in cost-effectiveness, renewable resource utilization, and operational flexibility. Users with higher demand or better load–generation matching gain greater economic returns, which can provide decision-making guidance for the government in formulating differentiated subsidy policies. Full article

Timber construction is increasingly promoted in Chile as a route to low-carbon, energy-efficient housing, yet public acceptance remains decisive for its diffusion. This study reports the first large-scale perception survey of timber buildings in Greater Concepción (N = 200) and contrasts key results with an earlier identical survey in Valdivia. Concepción residents strongly recognise timber’s thermal comfort attributes and associate wood housing with lower winter heating demand, a perception markedly stronger than in Valdivia. Conversely, 73% of Concepción respondents believe timber homes burn easily, but a majority also accept that modern engineering can mitigate this risk, indicating scope for targeted technical communication. Environmental perceptions are more ambivalent: although respondents value wood’s renewable origin, 42% doubt that timber construction reduces climate change, and many equate it with deforestation, echoing controversies around Chile’s plantation model. Cluster analysis reveals a techno-optimist subgroup coupling enthusiasm for energy savings with confidence in fire-safety innovations, suggesting a strategic constituency for demonstration projects. By situating end-user attitudes within national decarbonisation goals, this paper argues that region-specific outreach—emphasising verified energy-efficiency gains, certified sustainable forestry and visible fire-safety performance—can convert passive approval into active demand and accelerate Chile’s transition to a net-zero housing stock. Full article

The electrification of rural medical centers in high Andean areas represents a critical challenge for equitable development due to limited access to reliable energy. Hybrid Renewable Energy Systems (HRESs), which combine solar photovoltaic generation, Battery Energy Storage Systems (BESSs), and backup diesel generators, are emerging as viable solutions to ensure the supply of critical loads. However, their effective implementation requires optimal sizing methodologies that consider multiple technical and economic constraints and objectives. In this study, an optimization model based on metaheuristic algorithms is developed, specifically, Genetic Algorithm (GA), Particle Swarm Optimization (PSO), and Ant Colony Optimization (ACO), to identify optimal configurations of an HRES applied to a remote medical center in the Peruvian Andes. The results show that GA achieved the lowest Life Cycle Cost (LCC), with a high share of renewable energy (64.04%) and zero Energy Not Supplied (ENS) defined as the amount of load demand not met by the system, significantly outperforming PSO and ACO. GA was also found to offer greater stability and operational robustness. These findings confirm the effectiveness of metaheuristic methods for designing efficient and resilient energy solutions adapted to isolated rural contexts. Full article