This study investigates the potential for solar energy to promote sustainable development in Nepal, focusing on financial viability, socioeconomic impact, and adoption issues in urban, rural, and remote areas. Using a mixed-methods approach, the study combines household surveys, expert interviews, statistical evaluations, and policy analysis. The findings show that solar adoption has effectively reduced reliance on fossil fuels and increased electricity availability, particularly in marginalized populations. However, fundamental impediments remain, such as high startup expenses, low public awareness, insufficient maintenance infrastructure, and inconsistent policy implementation. Surveyed families reported significant cost savings and increased energy security, but adoption trends differed by region. Urban areas benefited from stronger infrastructure and financial support, whereas outlying regions faced persisting logistical and economic challenges. Although government subsidies reduced budgetary restrictions, inefficiencies in distribution and ambiguous qualifying requirements limited their effectiveness. Experts stressed the need of local technical skills and ongoing maintenance support. Economic assessments, such as cost-benefit and levelized cost of electricity (LCOE) analyses, show that solar energy becomes more cost-effective over time. The paper concludes with recommendations for targeted legislative reforms, enhanced subsidy systems, and more public-private collaboration to increase solar adoption. These initiatives are vital for achieving Nepal's energy security goals and advancing its commitments to environmental sustainability.
This study investigates the techno-economic potential of deploying community solar in stormwater detention basins located in or near Low- and Moderate-Income (LMI) households to reduce energy costs and offset environmental emissions. Focusing on communities with limited access to traditional rooftop solar due to physical, financial, or regulatory constraints, the paper analyzes the technical viability, economic feasibility, and environmental benefits of this approach across four Southcentral U.S. states: Texas, Oklahoma, New Mexico, and Louisiana. The analysis evaluates the spatial and techno-economic feasibility of community solar for both traditional households (electricity and natural gas) and all-electric households, modeling energy use and system performance under varying pricing and incentive scenarios. Results indicate that all-electric communities required smaller solar systems than traditional households, reflecting lower energy demand and evolving grid emissions trends. From a technical perspective, only communities selected in Louisiana and New Mexico had sufficient basin area to support viable systems, while those in Texas and Oklahoma faced spatial limitations. Economically, floating solar systems proved more cost-effective than carport-type systems. New Mexico's all-electric floating solar configuration achieved profitability, whereas the Louisiana case required significant incentives to break even. Environmentally, emissions reductions ranged from 103% to 214% annually, demonstrating strong potential to support residential sector decarbonization. These findings highlight community solar detention basins as a promising strategy to provide more equitable access to renewable energy, reduce residential emissions, and alleviate energy poverty. However, spatial and financial barriers necessitate tailored policy support to enable widespread adoption across diverse regional contexts.
This study presented a sustainable methodology for designing collagen-based biomaterials by using natural reinforcing agents and environmentally friendly cross-linking to improve water absorption, water retention and thermal stability − key features for biomedical and environmental applications. Collagen films were enhanced with keratin and natural polysaccharides (carboxymethyl cellulose, microcrystalline cellulose, acacia gum, soy protein, and carrageenan), then cross-linked by Vitex agnus-castus (VAC) extract as an eco-friendly alternative for synthetic cross-linkers. Glutaraldehyde was used for comparative analysis. A series of comprehensive analyses were conducted, including Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and water absorption testing. Among all compositions, films containing 30% acacia gum and 3% VAC demonstrated the highest water absorption and retention capacity (5.90 g/g after 48 h) and enhanced thermal stability, with the minimal weight loss observed at 600 °C. FTIR analysis confirmed enhanced molecular connections through cross-linking, while DSC results validated increased structural resilience. The results indicated that VAC serves as both a structural and functional cross-linker, facilitating the creation of biodegradable, thermally resilient, and moisture-retentive films. This natural system presents significant potential for wound dressing and other biomedical applications within a sustainable material framework.
Construction projects are associated with huge amount of embodied and operational energy. Therefore, the construction industry contributes significantly to the emission of energy related greenhouse gases (GHGs). Adopting sustainable green construction and the concept of net-zero energy buildings (NZEB) could reduce GHGs emissions from the construction sector and lower its contribution to global warming. However, implementing NZEB comes with different challenges, especially for developing countries. One of the main challenges is the lack of interest from landlords, property developers and investors. Motivating and empowering construction stakeholders to embrace the NZEB approach are crucial for developing countries aiming to lower their GHGs emissions. However, assessment and verification of NZEB face challenges in these countries due to the absence of viable assessment methods that consider local and national needs. Simplification of the process could encourage property developers to be engaged and adopt the concept of NZEB. This paper aims to propose a simplified approach for the assessment of sustainability of buildings. It provides property developers and stakeholders with a viable and affordable tool that produce timely results to demonstrate the sustainability of their new developments. The proposed approach eliminates several costly and time-consuming aspects and focuses on main factors within the three primary phases of construction projects; design, construction and operation. The implementation of the proposed simplified approach is illustrated, and it has been shown that the approach is viable, simple and easy to apply. It could lead to significant savings in energy and reduction in the associated GHGs.
In a climate change scenario that is increasingly affecting our daily lives, it is essential to rethink the reuse of existing resources and avoid the exploitation of raw materials. If we consider the stock of existing buildings in Italy, we cannot ignore the fact that most of them are in a state of decay or in need of major maintenance; the recovery or demolition of these buildings generates a considerable amount of waste that has a negative impact on the environment, from transport to disposal. A sustainable design approach can achieve interesting results in terms of economic, environmental and social impact. Starting from the final phase of the life cycle of buildings, this paper aims to show the possibilities of recovering traditional building materials such as cement, brick and tuff. The use of innovative production technologies will allow the reintroduction of these materials to the market, with consequent benefits in all aspects of the ‘sustainability triad'. The aim of the work is to identify a practical, easy-to-use process for the production of eco-sustainable materials that, while retaining their intrinsic chemical-mineralogical characteristics, can be easily used in the context of the existing built heritage thanks to the compatibility between these new materials and the pre-existing substrate. The innovative results obtained as part of an international research project show how the use of demolition waste for the composition of geopolymer mixtures allows the reuse of large percentages of construction waste, while guaranteeing the mechanical performance of materials produced with traditional techniques, which have a high level of emissions; the production of geopolymers allows an 80% reduction in emissions compared to the production of Portland cement. The paper is intended to serve as a starting point for further in-depth application of the mixtures produced and to provide reflections and future research directions.
The sizing of the energy components is essentially designed to prevent outages and ensuring the reliability of the power supply. This paper focuses on the development of a stand-alone photovoltaic/battery/fuel cell power system considering the demand of load, generating power, and effective multi-storage strategy using a probabilistic sizing algorithm. A computer program was developed and used in the design of component sizing configuration of a stand-alone power system that comprises of a photovoltaic generator (PV), battery, water electrolyzer, a storage gas tank, a fuel cell, and an inverter for a reliable power supply. This program manages the energy flow through the various components of a stand-alone PV/battery/fuel cell power system and provide an optimal technical configuration. The optimum system configuration of a residential building with daily power demands of 69 kWh/day energy consumption is composed of PV arrays resulting in total rated power of 15 kW, 16 units of 6 V, 225 Ah battery bank, 5.5 kW fuel cell, 5.5 kW Water Electrolysis, 16.5 kg hydrogen tank, and a 5.5 kW inverter. Based on the simulation results conducted, it was shown that the sizing and development of a stand-alone PV/battery/FC energy system have been achieved with system reliability (loss of power supply equal to zero). This program could be used as a power monitoring and control system for a stand-alone PV/battery/fuel cell power system.
Energy performance and comfort condition improvements in buildings is a current issue, fixed by a stringent European regulatory framework that point to reduce emissions from buildings with increasingly objectives of renovation. Especially for historical built, which in Italy represents a large part of the buildings, the renovation must be face as a process, centred on the energetic profile knowledge. This article, part of a doctoral research, elaborates a methodology based on reading multiple energy datasets towards evaluating energy consumption and giving real prospects of improvements. Through the case study of Spelonga − an historical centre in the Marche region − the informative dataset of this process flows into an easy-to-consult digital platform, addressed local administrations to implement the energy governance and more awareness in the planning of the territory.
The powertrain in electric vehicles typically comprises various components, including lithium-ion batteries (LIBs), a battery management system, an energy converter, an electric motor, and a mechanical transmission system. Electric vehicles utilize the electrical energy stored in LIBs to efficiently drive the motors efficiently. LIBs find widespread use in portable electronic devices like laptops, mobile phones, and other electronic appliances, with potential applications in the automotive sector. To examine the thermal performance of LIBs across diverse applications and establish accurate thermal models for batteries, it is essential to understand heat generation. Numerous researchers have proposed various methods to determine the heat generation of LIBs through comprehensive experimental laboratory measurements. This study comprehensively explores diverse experimental and modeling techniques used to analyze the thermal behavior and heat generation of LIBs.
In being aware of certain factors as the increasing of the pollution levels, the effects of the Urban Heat Island, or all the extreme climate events attributable to the constant increasing of CO2 emissions. This paper intends to propose an innovative approach to design systems and components that allow to adapt the built environment and mitigate the effects of the Climate Change in the urban Mediterranean areas. An experimental investigation at the building scale was conducted to study the environmental aspects in the early design phase that incorporate circular and ecological materials. The physical interactions between the built and the natural environment is enhanced with the upcycling design of the “Liminal Space” through the prototypological model for the “Green Responsive System”. The focus on the LS needs to push the technological definition beyond the concept of building envelope, just as the element of internal/external separation. The LS is where the “Advanced Circular Design” model can improve with the design of the GRS all the technological elements of adiabatic nature. The proposed framework enables the GRS to have a dynamic and systemic answer to the extreme change of the climatic situation in order to have a strong impact on the performance related to the environmental aspects. The parametric tools in the ACD model offers an important digital interface that can include all the regenerative requirements of the entire building considering the embodied CO2 emissions, the production and the energy consumption during the operational phase, and at the same time to control and improve the recyclability of all its components. The structure of the paper is presented as a succession of digital and physical design processes that identify all the phases for the definition of the GRS when it works on the LS. This becomes a central node in the development of the methodological framework for the upcycling design and the digital control of the responsiveness in the technological systems used for the integration of the physical aspects and the digital devices by using circular materials.
Due to a well-established infrastructure developed over the years, fossil fuel-based energy remains the predominant global energy source. Nevertheless, with heightened global attention towards addressing climate change concerns, there has been an increased focus on green energy technologies across various sectors. The advancement of distributed renewable power generation technologies such as solar photovoltaics (PV), wind, wave, tidal, etc., has contributed to a growing independence of power consumers from centralized grids, leading to a pronounced shift towards distributed microgrids. Notably, numerous electrical devices operate on DC power, aligning with the DC power output of many distributed renewable sources. Consequently, the concept of DC microgrids is gaining traction. Amid this context, fuel cells have resurged in prominence on a global scale, alongside the development of hydrogen economies. Given fuel cells DC-based nature, they are well-suited to explore new frontiers within DC microgrids. However, the seamless integration of fuel cells into DC microgrids requires effective power electronic interfacing. Thus, a comprehensive examination of the integration of fuel cells into DC microgrids becomes imperative. This article aims to address this gap by offering an extensive review of fuel cell technologies, the landscape of DC microgrids, and the prevailing context of control architectures. Notably, this review article fills an existing void in the literature by consolidating the key elements into a unified discussion.
Escalating energy tariffs and peak cooling demands due to climate change along with expanding use of variable renewable energy supply are presenting new challenges and opportunities for air conditioning system operation and control. This research presents the outcome of an investigation into the use of a thermal battery using salt-hydrate phase change material (PCM) in commercial buildings. A 1.2 m3 modular thermal battery using 15 °C melting temperature salt-hydrate PCM has been designed and fabricated. Its cooling performance and feasibility of integration into a chilled water-cooling system of commercial buildings has been comprehensively investigated. This storage unit can accommodate approximately 52 kWh of energy, featuring a rapid heat discharge rate of 32.58 kW during the initial 30 min to effectively address sudden cooling demands. The overall heat discharge rate closely aligns with simulation results, reaching approximately 96% accuracy. This has been achieved through optimisation of the heat exchanger design through mathematical simulation, detailed testing to match various operational scenarios and evaluation of economic and peak load shifting benefits. The results demonstrate the environmental and economic effectiveness of the PCM thermal battery as an independent component in building cooling systems. It provides a timely response to peak cooling demand and improves thermal comfort of the buildings.
This study provides evaluation of floating photovoltaics (PV) in the Brazil tropical climate and discusses the specific technical and environmental benefits and limitations. This paper develops a model simulating the annual performance of the photovoltaic generator of a floating photovoltaic plant as a function of a given conditions. The reference is a 1.2-MWp floating-PV system commissioned in 2023 near the city of Grão Mogol, Brazil, in the reservoir of the PCH Santa Marta hydropower plant. The influence of the ambient meteorological and marine parameters on the PV module temperature, current, voltage, and power were evaluated. The simulation uses a reference crystalline-Si PV module and the Engineering Equation Solver (EES). Relevant experimental data, including incident solar radiation, ambient temperature, and wind speed were used as input data for the model. The effect of these parameters on the thermal end electrical parameters was assessed. Although small variations were found throughout the year, significant hourly and daily variations were observed, depending on solar irradiation and ambient and resulting module surface temperatures. The voltage at the maximum power decreases with the increase of the solar module surface temperature. The convective heat transfer rates are higher than the radiative heat transfer rates. This study provides a first-time complete energy and exergy analysis of a floating PV system (FPVS) incorporating the various heat transfer rates, electrical and irradiance parameters, under climate and meteorological conditions for this Brazil location.
Distributed Generators (DG) systems based on Renewable Energy Sources (RES) such as hydro, wind, and solar power plants have been spread widely due to their lower cost and the advanced capability of connecting them with the grid. The power generated from the DG must be shaped to be interfaced with the grid employing power electronics converters. The grid-connected power electronics converters must be synchronized with the grid (i.e., the same fundamental component of the grid frequency, phase, amplitude, and sequence). Synchronization techniques are employed to achieve accurate and fast grid synchronization between the converter and the grid. The existence of (DC-offset) in the input of Phase Locked Loop (PLL) caused synchronization problems as it causes oscillations in the estimated fundamental grid phase, frequency, and amplitude. In addition, the closed-loop system stability can be affected. This work proposes a simple technique for grid synchronization based on PLL with a phase angle correction. The proposed method was developed using Transfer Delay (TD) and Delay Signal Cancelation (DSC) operators; then, the small single model and stability analysis was employed. Several scenarios were developed to compare the proposed method with previous methods using MATLAB/Simulink tool. The scenarios involve introducing phase jumps, DC offsets, and amplitude changes to the grid voltage. Additionally, the grid frequency was also changed. The results show that the proposed PLL can solved the DC-offset problem using any delay time and fully synchronized with the grid. Moreover, the proposed PLL has the fastest dynamic response and shortest synchronization time over the other methods from literature.
The residential sector is a substantial consumer of energy in Spain. A new electricity tariff was applied in Spain to make home consumers manage their energy consumption based on the variation of electricity price during the day, which contributes to energy security, increases the penetration of Renewable Energy Sources (RES) into the grid, maintains grid stability, and reduce CO2 emissions. To ensure the successful implementation of the new Demand Response (DR) program, it is necessary to investigate the factors that might affect home energy consumers to use the Home Energy Management System (HEMS). This work aims to examine the factors that affect the Spanish home energy consumers' acceptance to participate in DR, which have not been studied yet after the new electricity tariff. In addition, highlighting the role of economic benefits and environmental awareness factors in the acceptance of participating in DR using HEMS. The Technology Acceptance Model (TAM) is used in this work with four independent factors, attitude toward use as a mediating effect, and one dependent variable of intention to use, then hypotheses were set for each. The selected research method was a diagnostic survey technique through a standardized survey questionnaire distributed in person and online, that Galicia, Northwest Spain was taken as a case study. In terms of the statistical results of Probability value (P-value) and Critical Ratio (C.R.), it was found that the family's economic benefits and environmental awareness affect the attitude toward using HEMS after the new electricity tariff in Spain and attitude toward using HEMS has a significant impact on the intention to use HEMS. However, the usefulness and ease of using HEMS for managing energy consumption do not influence the consumers' attitudes toward adopting HEMS. The direct effect of usefulness on the intention of using HEMS is higher than the indirect effect through attitude. Thus, the mediating effect of the attitude to the relationships between usefulness and intention to use is not significant. The results help the Spanish policymakers to draw up policies to effectively disseminate strategies to encourage home consumers to contribute to energy security and assist energy management researchers in incorporating key factors that impact energy consumers into their proposed models. By doing so, these models can clarify the financial and environmental advantages of effective energy consumption management, thereby encouraging energy consumers to adopt more sustainable practices.
This paper presents the design and development of an integrated hybrid Solar-Darrieus wind turbine system for renewable power generation. The Darrieus wind turbine's performance is meticulously assessed using the SG6043 airfoil, determined through Q-blade simulation, and validated via comprehensive CFD simulations. The study identifies SG6043 as the optimal airfoil, surpassing alternatives. CFD simulations yield specific coefficients of power (0.2366) and moment (0.0288). The paper also introduces a hybrid prototype, showcasing of 10 W photovoltaic module and improved turbine performance with the SG6043 airfoil. The focus extends to an optimized hybrid PV solar-wind system seamlessly integrated with IoT technology for remote monitoring. Addressing weather challenges, the research suggests blade shape optimizations via Q-blade and an IoT-based solution leveraging the ESP32 Wi-Fi module. Theoretical results project electrical energy generation ranging from 0.88 kW on March 14, 2023, to 0.06 kW on February 20, 2023. Darrieus wind turbines, experiencing increased blade drag, require less lift to operate. Experimental and theoretical results converge well, affirming the model's reasonable assumptions. Beyond advancing renewable energy technologies, this research sets the stage for future investigations aimed at enhancing the efficiency and capabilities of hybrid wind-solar PV systems.
Brazil's cumulative photovoltaic (PV) installations have now surpassed 32 GWp. The fastest growing and most prevalent PV technology is the bifacial photovoltaic module, which is now being incorporated in more than 2/3 of new power plants. These modules collect solar radiation on both front and rear sides, providing gains in electricity production compared to traditional monofacial modules. The market acceptance and quality control of this technology requires standard methods to accurately determine the nominal power of the bifacial modules. But the specification of energy production from the bifacial backside is complicated due to critical factors that include the albedo, the separation, height, and positioning of the modules, the shading of the rear surface, and the specific geographic and climate conditions. This paper addresses these issues in determining the performance of bifacial PV modules in the tropical conditions of the State of Minas Gerais, Brazil. Specifically, the bifacial gain for modules and systems is evaluated, assessing the effects of albedo, site maintenance, climate/environmental conditions, thermal behavior, and back-surface shading. The special cases of tracking versus non-tracking systems are evaluated showing specific attention needs to the albedo changes and rear module shading constraints. These studies are performed on real power plants having different operating conditions (e.g., tracking, non-tracking, ground cover). The methodology includes I-V characterization of modules and string and thermal imaging/mapping under existing climate and meteorological conditions. Correlations with experimental albedo conditions is a special concern with these studies. These results are further compared to controlled laboratory measurements to establish information needed to better evaluate the developing standard for actual local operating conditions. This case study provides evaluation of the quality of the both the bifacial PV products being used and their installations in the rapidly emerging Brazil PV markets.
The pandemic of COVID-19 crisis suddenly appeared worldwide, and there were no proper crisis management procedures taken in advance to contain such a problem. Moreover, it has had harmful and unmeasured consequences on most life sectors, including construction, which has been severely impacted during the pandemic. This paper aims to review factors with a high-risk impact on hospitals' construction projects during the outbreak of COVID-19 in developing countries by considering the case of Iraq's construction sector. A mixed methodology of qualitative and quantitative research approaches was used. The qualitative method involved (1) a literature review and (2) semi-structured interviews to identify high-risk factors that affect construction projects during the outbreak of COVID-19. The quantitative method involved (1) collecting survey data from 205 industry professionals and experts to determine each risk factor's importance and influence. Cronbach's alpha test to check the reliability of the collected data set, and (3) a fuzzy inference system method was used to assess the impact of each factor on construction projects during the pandemic. The findings of this study indicate that the construction industry has been hit severely during the COVID-19 in Iraq. Moreover, 17 high-risk sub-factors under six main construction factors involve health and safety, risk management, management deficiency, financial, supply chain management and contractual impact hospital construction projects. Furthermore, the most significant risk factors had impacted hospital construction projects by calculating their means were (1) commitment to safety and health recommendations with a level of impact equal to 4.81; (2) risk management procedures with a level of impact equal to 4.63; (3) equipment delivery delays with a level of impact equal to 4.54; (4) worker acceptance of COVID-19 vaccination with a level of impact equal to 4.36; (5) increase of price material with a level of impact equal to 4.18; (6) lack of use of the latest technology with a level of impact equal to 4.09; (7) delay in payments with a level of impact equal to 3.90; and (8) lack of training to deal with the pandemic with a level of impact equal to 3.81. As such, this paper contributes by providing effective policies and measures to mitigate the impact of COVID-19 on hospital construction projects in Iraq.
With the expansion of renewables in the electricity markets, research on electricity storage economics is needed for a better understanding of the utilization of these systems and for improving the performance of intermittent variable generation. Collected up-to-date research of electricity storage systems published in a wide range of articles with high impact factors gives a comprehensive review of the current studies regarding all relevant parameters for storage utilization in the electricity markets. Valuable research of technical characteristics from the literature is broadened with the electricity storage analyses from an economic point-of-view. Analysis of selected technologies, considering different perspectives such as their profitability, technical maturity, and environmental aspect, is a valuable addition to the previous research on electricity storage systems. Comparing conducted analysis with the selected literature, electricity storage technologies are analyzed concerning their viability in the electricity markets. Given the current outlook of the electricity market, the main problems for storage's wider integration are still energy storage costs. These can be overcome with different applications of energy storage systems, integration of new market players, or a combination of storage technologies along with the implementation of new energy policies for storage.
Bioelectrochemical systems (BESs) can be integrated in situ into anaerobic digesters for increasing methane (CH 4 ) content of biogas. Using BES ex situ for improving biogas quality has recently been gaining attention. However, information on the process under thermophilic conditions is very limited. In this study, we placed a BES cathode in-line at the exit gas from a thermophilic anaerobic digester to convert carbon dioxide (CO 2 ) in the biogas into CH 4 . The performance of the ex situ BES reactor under thermophilic conditions was evaluated. When poising the cathode at −1.1 V versus Ag/AgCl in the ex situ BES reactor, CH 4 content increased from 50% to 85%. Of the incoming CO 2 73% was biologically converted to CH 4 and 23% absorbed by alkalinity generated in the cathode. The energy output as additional CH 4 as a percentage of the energy input to operate the BES was calculated at 56%. The biocathode of the BES reactor was dominated by Methanothermobacter spp., which are thermophilic hydrogen consuming methanogens. This study confirms that thermophilic BES can be used as an ex situ treatment process for enriching the CH 4 content of biogas. However, energy efficiency of the process was found to be limited by the lack of an energetically efficient anodic reaction. For industrial applications, optimisation of energy efficiency is an area for further research.
This paper investigates the thermal performance of green roofs, cool roofs, and their combined effects in tropical climates. Although each technology has been studied independently for its potential to reduce cooling energy consumption in buildings, their combined effects have not been thoroughly examined in tropical climates. The study employed experimental and numerical methods, demonstrating that combining green and cool roofs can lead to even greater cooling energy savings. The research involved fabricating four identical cubicles made of mild steel sheets and placing them in an open space for testing under two operational conditions: closed window and open window/door. The combined green and cool roof technology achieved a temperature difference reduction of 4.14 °C compared to the original roof under the closed window and door state, with green and cool roofs achieving 0.72 °C and 0.79 °C, respectively. Combining green and cool roofs led to even more significant cooling energy savings, with 53.57 kWh energy savings compared to 20.1 kWh and 3.68 kWh for combined, green, and cool cubicles, respectively. The study found that combining green and cool roofs led to even more significant cooling energy savings, with 53.57 kWh energy savings compared to 20.1 kWh and 3.68 kWh for combined, green, and cool cubicles, respectively. The research suggests that combining these technologies can lead to greater cooling energy savings and highlights the potential benefits of green and cool roofs for tropical climates.
