Search Results (31)

The rapid rise in atmospheric CO₂ concentrations has intensified the need for scalable, sustainable, and economically viable carbon sequestration technologies. This study introduces a cost-effective CaO/Ca(OH)₂-based mineralization process that not only enables efficient CO₂ removal but also allows the simultaneous recovery of high-purity calcite nanoparticles as value-added products. The process involves hydrating CaO, followed by controlled carbonation under optimized CO₂ flow rates, temperature conditions, and and additive use, yielding nanocrystalline calcite with an average particle size of approximately 100 nm. Comprehensive characterization using X-ray diffraction, transmission electron microscopy, and energy-dispersive X-ray spectroscopy confirmed a polycrystalline structure with exceptional chemical purity (99.9%) and rhombohedral morphology. Techno-economic analysis further demonstrated that coupling CO₂ sequestration with nanoparticle production can markedly improve profitability, particularly when utilizing CaO/Ca(OH)₂-rich industrial residues such as steel slags or lime sludge as feedstock. This hybrid, multi-revenue strategy—integrating carbon credits, nanoparticle sales, and waste valorization—offers a scalable pathway aligned with circular economy principles, enhancing both environmental and economic performance. Moreover, the proposed system can be applied to CO₂-emitting plants and facilities, enabling not only effective carbon dioxide removal and the generation of carbon credits, but also the production of calcite nanoparticles for diverse applications in agriculture, manufacturing, and environmental remediation. These findings highlight the potential of CaO/Ca(OH)₂-based mineralization to evolve from a carbon management technology into a platform for advanced materials manufacturing, thereby contributing to global decarbonization efforts. Full article

This study presents a novel policy-integrated optimization framework for utility-scale hybrid power plants (HPP), including wind–solar–battery, addressing a critical gap in hybrid renewable energy system design by simultaneously evaluating technical, operational, and economic performance under dynamic policy environments. Unlike conventional approaches that treat these factors separately, this multi-objective optimization model uniquely combines (1) technical reliability assessment through Loss of Load Probability (LOLP) metrics, (2) operational efficiency analysis via curtailment minimization, and (3) economic viability evaluation using net present value (NPV) optimization—all while accounting for policy incentive structures. Applying this framework to comparative U.S. and India case studies reveals how tailored policy combinations can enhance project viability compared to single-incentive scenarios. The results indicate that HPPs are financially unviable without policy support, but targeted incentives like Investment Tax Credits (ITCs) and Production Tax Credits (PTCs) in the U.S. and Accelerated Depreciation (AD), Generation-Based Incentives (GBIs), and Viability Gap Funding (VGF) can improve their viability. The U.S. scenario sees a 197% increase in NPV and a reduction in LCOE to USD 0.055/kWh, while India achieves a 107% turnaround in NPV and an LCOE of USD 0.039/kWh. Sensitivity and breakeven analyses reveal that interest rates and consistent policy support are critical, especially in emerging markets. Specific policy thresholds are identified for feasibility, providing actionable benchmarks. By bridging the gap between technical optimization and policy analysis, this work provides both a methodological advance for HPP design and practical insights for policymakers seeking to accelerate HPP. While this study centers on incentive-driven feasibility, it also outlines key modeling limitations and future improvements, such as market participation, environmental constraints, and advanced system design that will support future HPP planning. Full article

This study presents an optimization framework for a utility-scale hybrid power plant (HPP) that integrates wind power plants (WPPs), solar power plants (SPPs), and battery energy storage systems (BESS) using historical and probabilistic weather modeling, regulatory incentives, and multi-objective trade-offs. By employing multi-objective particle swarm optimization (MOPSO), the study simultaneously optimizes three key objectives: economic performance (maximizing net present value, NPV), system reliability (minimizing loss of power supply probability, LPSP), and operational efficiency (reducing curtailment). The optimized HPP (283 MW wind, 20 MW solar, and 500 MWh BESS) yields an NPV of $165.2 million, a levelized cost of energy (LCOE) of $0.065/kWh, an internal rate of return (IRR) of 10.24%, and a 9.24-year payback, demonstrating financial viability. Operational efficiency is maintained with <4% curtailment and 8.26% LPSP. Key findings show that grid imports improve reliability (LPSP drops to 1.89%) but reduce economic returns; higher wind speeds (11.6 m/s) allow 27% smaller designs with 54.6% capacity factors; and tax credits (30%) are crucial for viability at low PPA rates (≤$0.07/kWh). Validation via Multi-Objective Genetic Algorithm (MOGA) confirms robustness. The study improves hybrid power plant design by combining weather predictions, policy changes, and optimizing three goals, providing a flexible renewable energy option for reducing carbon emissions. Full article

The construction sector plays a pivotal role in sustainability efforts, driving the need for innovative solutions like Building Information Modeling (BIM) to optimize green building design and performance. This study examines the diffusion of BIM functionalities that support sustainability, particularly in energy efficiency, water management, material selection, indoor environmental quality, and green building certification. Using the innovation diffusion theory, the research employs three mathematical models—internal, external, and mixed—to analyze the adoption patterns of BIM for green building applications. Empirical findings reveal that external factors, such as government regulations, financial incentives, and industry trends, significantly influence the diffusion of BIM functions related to environmental performance. The mixed diffusion model demonstrates the highest explanatory power, indicating that both external and internal drivers play a role, particularly in material selection and lifecycle assessment. This study highlights the growing integration of BIM in sustainable construction, reinforcing the need for regulatory support to accelerate adoption. These findings offer valuable insights for researchers, policymakers, and industry professionals, demonstrating how BIM can drive greener practices in the built environment. Policymakers should focus on developing policies and offering incentives such as feed-in tariffs, investment tax credits, and integrating Green BIM requirements into building codes to encourage sustainable construction practices. Also, curricula should be updated to include real-world projects and experiential learning to improve the adoption and efficiency of Green BIM practices. Future research should explore enhanced digital frameworks to further improve BIM’s impact on sustainability and lifecycle optimization. Full article

Sustainable development in educational environments requires a holistic approach to architectural design, balancing multiple environmental functions to optimize student well-being and energy efficiency. According to architectural standards, rectangular classrooms typically have a shallow proportion, meaning the external facade is longer than the internal sides. While this design ensures adequate natural lighting, essential for classroom visual functions, it may not fully align with the sustainability goals in regions with diverse environmental characteristics. This diversity can lead to shortcomings in other aspects of human comfort or environmental performance, as optimizing one function may negatively impact others, while the environmental efficiency of architectural spaces should not be judged solely on a single comfort criterion. A holistic study should evaluate common architectural shapes and proportions to ensure they align with the Green Architectural principles for specific locations. This manuscript compares eight rectangular classrooms with different external-to-internal wall proportions and window-to-wall ratios (WWR) to determine their suitability for Taif City, KSA schools. The case studies include variations in window sizes (10.5 m² and 14 m²) and orientations (North and South), providing a comprehensive evaluation of their impact on human comfort. Simulation results reveal that the common classroom proportion did not yield the highest green credits, suggesting it may not be optimal for all regions, including Taif City. The findings emphasize the need to reconsider standard classroom dimensions to better align with local environmental conditions and Green Architecture principles, contributing to the broader goals of sustainability and sustainable development in educational infrastructure. Full article

Identifying factors that influence the choice of Leadership in Energy and Environmental Design (LEED) certification strategies for existing office building projects in the United States is a pressing issue requiring attention as it will help LEED professionals select the optimal certification strategy for each project. In this context, a quantitative research methodology with purposive sampling was used in this study to evaluate the impacts of project/building characteristics in LEED for Existing Buildings version 4 (LEED-EB v4) gold-certified projects in the U.S. LEED-EB v4 project/building characteristics include the project size and the number of buildings built before and after the 1973 energy crisis. LEED-EB-certified projects include a score for Location and Transportation credit (LTc1, “alternative transportation”) and scores for Energy and Atmosphere credits (EAcs) (EAc6, “renewable energy and carbon offsets”, and EAc8, “optimize energy performance”). From 112 LEED-EB v4 projects, the two following groups of projects with specific achievements were selected: Group 1 (n₁ = 13), which included high achievements in LTc1 and low achievements in EAc6 and EAc8, and Group 2 (n₂ = 13), which included high achievements in LTc1, EAc6, and EAc8. Exact Wilcoxon–Mann–Whitney and Fisher’s exact 2 × 2 tests were used to estimate significant differences between the two groups. The results of the selection of LEED-EB-certified projects in Groups 1 and 2 were that Group 2 outperformed Group 1 in EAc6 and EAc8 (p < 0.0001), while there was no significant difference between Groups 1 and 2 in LTc1 (p = 0.199). As a result, Group 1 outperformed Group 2 in LEED-EB v4 project size (p = 0.017). Group 2 outperformed Group 1 in the number of LEED-EB v4 gold-certified projects in buildings constructed after the 1973 US energy crisis (p = 0.005). It is concluded that, when choosing a LEED certification strategy for existing office buildings in the United States, LEED professionals should consider the 1973 energy crisis and the size of the LEED project. Full article

This study investigates the effectiveness of combining magnets with parabolic and truncated fins in enhancing the distillation process of solar stills. The integration of magnets accelerated evaporation rates, while the fins increased the heat absorption area, resulting in improved output, vis-à-vis traditional solar stills. A comparative assessment revealed that the parabolic fin solar still (PFS) with magnets outperformed the truncated fin solar still (TCFS), producing 20%, 15%, and 16% more distillate at three different depths (1, 2, and 3 cm). The superior performance of the PFS is attributed to the magnetism of the water and the fins’ more extensive surface area for heat absorption. Efficiency measurements at a water depth of 1 cm showed that the PFS achieved the maximum energy and exergy efficiencies at 30.49% and 8.85%, respectively, compared with TCFS’s 25.23% and 6.22%. Economically, the PFS setup proved more feasible, with a 20.9% lower cost per liter of distilled water than TCFS. Additionally, the environmental impact assessment indicated a significant reduction in CO₂ emissions, potentially generating revenues of approximately USD 1242.32 through carbon credits. These results reflect a considerable margin to enhance the efficiency of solar desalination through well-planned adjustments, which bodes well for the future of optimized solar distillation systems from an economic and environmental perspective. Full article

The distinct physicochemical characteristics of metal-free graphitic carbon nitride (g-C₃N₄) are gaining interest in various fields, including energy storage and conversion. However, the electrochemical performance of this material is constrained, owing to its minimal surface area. Incorporating a surfactant is one of the ways to resolve the issue of surface area and therefore improve the electrochemical performance of g-C₃N₄. This research delves into a method aimed at improving the supercapacitive capabilities of 2D g-C₃N₄ sheets through the implementation of a cationic surfactant, cetyltrimethylammonium bromide (CTAB). Electrochemical studies reveal that the CTAB-assisted g-C₃N₄ sheets exhibit remarkable improvements in specific capacitance, cyclic stability, and comparative rate capability in relation to pristine g-C₃N₄. The specific capacitance of g-C₃N₄ with CTAB exceeds about 28%, which gives 162. 8 F g⁻¹. This value is 117.7 F g⁻¹ for electrode material without CTAB at 0.5 mA cm⁻². This improved electrochemical performance can be credited to the heightened surface area, improved electronic conductivity, and optimized charge transfer kinetics facilitated by the CTAB surfactant. We aim to emphasize the enhancement of the overall performance of g-C₃N₄-based supercapacitors for advanced energy storage systems. Full article

The design for the remanufacturing process (DFRP) is a key part of remanufacturing, which directly affects the cost, performance, and carbon emission of used product remanufacturing. However, used parts have various failure forms and defects, which make it hard to rapidly generate the remanufacturing process scheme for simultaneously satisfying remanufacturing requirements regarding cost, performance, and carbon emissions. This causes remanufactured products to lose their energy-saving and emission-reduction benefits. To this end, this paper proposes an integrated design method for the used product remanufacturing process based on the multi-objective optimization model. Firstly, an integrated DFRP framework is constructed, including design information acquisition, the virtual model construction of DFRP solutions, and the multi-objective optimization of the remanufacturing process scheme. Then, the design matrix, sensitivity analysis, and least squares are applied to construct the mapping models between performance, carbon emissions, cost, and remanufacturing process parameters. Meanwhile, a DFRP multi-objective optimization model with performance, carbon emission, and cost as the design objectives is established, and a teaching–learning based adaptive optimization algorithm is employed to solve the optimization model to acquire a DFRP solution satisfying the target information. Finally, the feasibility of the method is verified by the DFRP of the turbine blade as an example. The results show that the optimized remanufacturing process parameters reduce carbon emissions by 11.7% and remanufacturing cost by USD 0.052 compared with the original process parameters, and also improve the tensile strength of the turbine blades, which also indicates that the DFPR method can effectively achieve energy saving and emission reduction and ensure the performance of the remanufactured products. This can greatly reduce the carbon emission credits of the large-scale remanufacturing industry and promote the global industry’s sustainable development; meanwhile, this study is useful for remanufacturing companies and provides remanufacturing process design methodology support. Full article

The Leadership in Energy and Environmental Design for Existing Buildings (LEED-EB) version 3 (v3) and version 4 (v4) gold-certified office space certification strategies in Spain have not yet been studied. The two purposes of this study were to evaluate (1) the impact of high or low achievements in the energy and atmosphere (EA) “optimize energy performance” credit (EAc1 for v3 and EAc8 for v4) on the compensation strategy for LEED “compensation group” credits and (2) the impact of EAc1-v3 or EAc8-v4 on the monotonic change in LEED “compensation group” credits. Data on a total of 77 LEED-EB v3 and 43 LEED-EB v4 gold-certified office space projects were collected. In the v3 group, 26 LEED-certified projects had the highest EAc1 achievements (v3 group 1), and 26 LEED-certified projects had the lowest EAc1 achievements (v3 group 2). In the v4 group, 15 LEED-certified projects had the highest EAc8 achievements (v4 group 1), and 15 LEED-certified projects had the lowest EAc8 achievements (v4 group 2). The exact Wilcoxon–Mann–Whitney test and Fisher’s exact 2 × 2 with Lancaster’s correction test were used to estimate the difference between groups 1 and 2. Spearman’s rank-order correlation was used to assess monotonic change in LEED credits. The results show that v3 and v4 group 1 outperformed v3 and v4 group 2 in EAc1 and EAc8 (p < 0.0001, respectively). However, v3 and v4 group 2 outperformed v3 and v4 group 1 in “renewable energy” (EAc4 for v3 and EAc6 for v4, p = 0.0039 and 0.0088, respectively) and “building commissioning” (EAc2.2 for v3, p = 0.0015; EAc3 for v4, p = 0.0560, respectively). EAc1-v3 and LEED v3 “compensation group” credits showed a moderate negative correlation (r_s = −0.53 and p < 0.0001). EAc8-v4 and LEED v4 “compensation group” credits showed a strong negative correlation (r_s = −0.74 and p < 0.0001). As a result, increasing the share of renewable energy and performing building commissioning in LEED-EB v3- and v4-certified projects occurred only as a compensation strategy in response to the low achievement in the “optimize energy performance” credit. Full article

Material selection is a challenging process in which several parameters should be considered for green-certified projects. Hence, this study investigates the dynamics of sustainable material selection (SMS) across the project life cycle using system thinking. A dynamic model was developed based on the Leadership in Energy and Environmental Design where relevant environmental categories and credits were represented, and their dependency coefficients (DCs) were computed. This pinpointed the effect of SMS on the point-accrual pattern across project phases, showing that the high leverage points were demonstrated for the operation phase. The result showed that SMS extended beyond the efficient use of materials, which indicated a DC of 100% in the Materials and Resources category to affect other sustainable categories, i.e., the indoor environmental quality, energy efficiency, and sustainability of the project site comprised 68.8%, 57.6%, and 50% of DCs, respectively. Thus, optimal SMS could earn the project 48% of the total possible points, putting it in the ‘Certified’ level. Accordingly, the proposed model can be used to evaluate the level of certification as well as the building performance therein. Full article

The aim of this study was to investigate strategies for the certification of environmentally friendly office buildings in Germany. A total of 39 LEED-NC gold-certified office space projects were ranked according to their “optimize energy performance” credit (EAc1) achievements from the energy and atmosphere (EA) category and divided into two groups: 13 projects (group 1) with the highest and 13 projects (group 2) with the lowest EAc1 achievements. Nonparametric statistics were used to evaluate the differences between groups 1 and 2. A two-stage nested analysis of variance test was used to evaluate the differences between the two groups in terms of their life cycle assessment (LCA). A comparison of the two groups showed that group 1 outperformed group 2 in the EA category (p < 0.0001). However, in the other LEED categories, the differences between the two groups were not significant (p ≥ 0.0761). As a result, group 1 outperformed group 2 in terms of overall LEED points (p = 0.0048). The LCA of EAc1 showed that group 1 enacted the lowest environmental damage when compared to group 2 (p = 0.0040). The environmental assessment of LEED-certified projects can help green building managers choose the most sustainable certification strategy. Full article

Electric substations (ESS) are important facilities that must operate even under contingency to guarantee the electrical system’s performance. To achieve this goal, the Brazilian national electricity system operator establishes that alternating current (AC) auxiliary systems of ESS must have, at least, two power supplies, and in the case of failure of these sources, an emergency generator (EG) must at least supply energy to the essential loads. In order to improve the availability of auxiliary systems, a microgrid with other sources, such as photovoltaic (PV) systems and Battery Energy Storage Systems (BESS), can be an alternative. In this case, an economical optimization of the PV/BESS system must be addressed considering the costs associated with the installation and maintenance of equipment, and the gains from the credits generated by the photovoltaic system in the net metering scheme. In this paper, the size of the BESS system was determined to supply energy to the load of auxiliary systems of an ESS, as well as a PV system to achieve a null total cost. Furthermore, multi-objective optimization using the genetic algorithm technique was employed to optimize the size of the hybrid PV/BESS to minimize the investment cost and time when the demand was not met. Simulations under different scenarios of contingency were allowed to obtain the Pareto frontier for the optimal sizing of a PV/BESS system to supply energy to AC auxiliary systems in an ESS under contingency. Full article

The purpose of this study was to explore green office building certification strategies in Shanghai. The 45 LEED-CI v4 gold-certified office space projects were sorted by energy and atmosphere credit (EAc6, optimize energy performance) into two groups: 15 projects with the lowest EAc6 achievement (Group 1) and 15 projects with the highest EAc6 achievement (Group 2). To reach the gold certification level in Group 1, high achievement in EAc6 is associated with low achievement in two indoor environmental quality credits (EQc2, low-emitting materials, and EQc8, quality views), while in Group 2, low achievement in EAc6 is associated with high achievement in EQc2 and EQ8. For the life-cycle assessment (LCA), the functional unit was designated as follows: production (P) stage: production of building materials needed to ensure the requirements of EQc2 and EQc8 for 1 m² of the building area; and operational energy (OE) stage: OE of 1 m² of the building area over 50 years of the building’s lifetime. For the OE stage, two fuel source scenarios were used: 71.07% coal + 28.08% natural gas + 0.81% wind power (WP) + 0.04% photovoltaic (PV) (Scenario 1) and 50% WP + 50% PV (Scenario 2). The results of the LCA (P + OE) showed that under Scenario 1, the LEED certification strategy in Group 1 was greener than that in Group 2. When using Scenario 2, no differences were found between the two groups. Full article

Over the last decade, it has been clearly shown that the same achievements in Leadership in Energy and Environmental Design (LEED) projects can lead to different life cycle assessments (LCAs). However, the problem of contradictory achievements in LEED and LCA has not yet been resolved. This study aimed to identify and evaluate different strategies for LEED projects using LCAs. Thirty-nine LEED projects with the same characteristics—location and transportation, rating system, rating version, certification level, and space type—were collected and sorted by their energy and atmosphere (EA) category, “optimize energy performance” credit (EAc6) achievement into three equal groups (EA_Low, EA_Medium, and EA_High, where each group includes 13 LEED projects) to minimize the influence of uncontrolled factors on the LEED project strategy. The author focused on two extreme groups with very different EAc6 credit scores: EA_Low (13 projects) and EA_High (13 projects). The groups were compared across LEED categories and credits. Wilcoxon–Mann–Whitney and Cliff’s $\delta$ test results showed that the EA_Low and EA_High groups are associated with high/low achievements in materials-related credits such as “interiors life cycle impact reduction”, “building product disclosure and optimization—material ingredients”, and “low-emitting materials”. As a result, the EA_Low and EA_High groups were reclassified into Energy_Low–Materials_High and Energy_high–Materials_Low certification strategy groups. In this context, LCAs were used to assess the differences between the two strategies. The results showed that if natural gas was used for operational energy (OE), the Energy_High–Materials_Low strategy showed lower environmental damage compared to the Energy_Low–Materials_High strategy ($p$ = 0.0635); meanwhile, if photovoltaic energy was used for OE, the Energy_Low–Materials_High strategy showed lower environmental damage compared to the Energy_High–Materials_Low strategy ($p$ = 0.0036). The author recommends using the LEED protocol and the LCA method in parallel to better reflect the environmental impact of different certification strategies. Full article