Search Results (841)

In recent years, the amount of electricity produced by photovoltaic systems in Poland has increased significantly. This paper presents an evaluation of commercial software (PVGIS 5.3, ENERAD, and PVGIS 24) used for simulating energy produced by four photovoltaic installations. The results of the simulation were compared with the real energy production. The installations differ in terms of panel orientation (S, SE, SE-NW), tilt angle (12°, 25°, 37°) and location (roof- or ground-mounted). The average annual electricity production per 1 kW of module power for each installation was as follows: PV1—1104 kWh·kW⁻¹, PV2—1169 kWh·kW⁻¹, PV3—927 kWh·kW⁻¹, and PV4—831 kWh·kW⁻¹. The highest values were recorded for ground-mounted installations facing south. Simulations carried out using computer programs show differences between simulated and real electricity production values of 35–41% for the ENERAD software, 3–13% for the PVGIS 5.3 software, and 3–32% for the PVGIS 24 software. The most accurate forecasts were obtained for the PV2 system in the PVGIS 24 software (MPE 3%, RMSE 12%), and the most unfavorable for the same installation in the ENERAD software (MPE 41%, RMSE 48%). Full article

High-rise building facades offer an alternative site for installing photovoltaic panels, which are traditionally placed on rooftops. The unique spatial configuration of high-rise buildings, characterized by a small footprint area relative to their height, supports the application of vertical facades for this purpose. Photovoltaic panels installed in these areas not only generate electricity but also enhance the aesthetic dimension of the urban landscape. The proposed methodology uses the EnergyPlus software to simulate the electricity generation of photovoltaic panels mounted on the walls of high-rise buildings in the city of Kragujevac, Serbia. A technical, economic, and environmental analysis was conducted for two scenarios: (1) photovoltaic panels installed on two facade areas with the highest solar potential, and (2) photovoltaic panels installed on all four available facade areas. In Scenario 1, the annual reduction in electricity consumption, annual cost savings in electricity consumption, and investment payback period range from 13 to 38%, 11 to 31%, and 8.4 to 10.6 years, respectively. In Scenario 2, these values range from 23 to 58%, 18 to 47%, and 10.9 to 12.9 years, respectively. The results indicate that southeast and southwest facades consistently achieve higher levels of electricity generation, underscoring the importance of prioritizing high-performing orientations rather than maximizing overall surface coverage. The methodology is particularly efficient for analyzing the solar potential of numerous buildings with comparable shapes, which is a characteristic commonly found in Eastern European architecture from the late 20th century. The study demonstrates the applicability of the proposed methodology as a practical and adaptable tool for assessing early-stage solar potential and providing decision support in urban energy planning. The approach addresses the identified methodological gap by offering a low-cost, flexible framework for assessing solar potential across diverse urban contexts and building typologies, while significantly simplifying the modeling process. Full article

This paper presents a performance evaluation of a 140 kW solar array installed on the rooftop of the Mountain Line Transit Authority (MLTA) building in Morgantown, West Virginia (WV), USA, covering the period from 2013 to 2024. The grid-connected photovoltaic (PV) system consists of 572 polycrystalline PV modules, each rated at 245 watts. The study examines key performance parameters, including annual electricity production, average daily and annual capacity utilization hours (CUH), current array efficiency, and performance degradation. Monthly ambient temperature and global tilted irradiance (GTI) data were obtained from the NASA POWER website. During the assessment, observations were made regarding the tilt angles of the panels and corrosion of metal parts. From 2013 to 2024, the total electricity production was 1588 MWh, with an average annual output of 132 MWh. Over this 12-year period, the CO₂ emissions reduction attributed to the solar array is estimated at 1,413,497 kg, or approximately 117,791 kg/year, compared to emissions from coal-fired power plants in WV. The average daily CUH was found to be 2.93 h, while the current PV array efficiency in April 2024 was 10.70%, with a maximum efficiency of 14.30% observed at 2:00 PM. Additionally, an analysis of annual average performance degradation indicated a 2.28% decline from 2013 to 2016, followed by a much lower degradation of 0.17% from 2017 to 2023, as electricity production data were unavailable for most summer months of 2024. Full article

Fuzzy logic has been applied to a wide range of problems, including process control, object recognition, image and signal processing, prediction, classification, decision-making, optimization, and time series analysis. These apply to solar energy systems. Though experts in renewable energy prefer fuzzy logic techniques, their contribution to the decision-making process of solar energy systems lies in the possibility of illustrating risk factors and introducing the concepts of linguistic variables of data from solar energy applications. In solar energy systems, the primary beneficiaries and audience of the fuzzy logic techniques are solar energy policy makers, as it concerns decision-making models, ranking of criteria or weights, and assessment of the potential location of the installation of solar energy plants, depending on the case. In a real-world scenario, fuzzy logic allows easy and efficient controller configuration in a non-linear control system, such as a solar panel. This study attempts to review the role and contribution of fuzzy logic in solar energy based on its applications. The findings from the review revealed that the fuzzy logic application identifies and detects faults in solar energy systems as well as in the optimization of energy output and the location of solar energy plants. In addition, fuzzy model (predicting), hybrid model (simulating performance), and multi-criteria decision-making (MCDM) are components of fuzzy logic techniques. As the review indicated, these are useful as a solution to the challenges of solar energy systems. Importantly, the integration and incorporation of fuzzy logic and neural networks should be recommended for the efficient and effective performance of solar energy systems. Full article

Climate change has prompted the adoption of sustainable measures to reduce greenhouse gas (GHG) emissions, particularly in urban transportation. The integration of renewable energy sources, such as solar energy, offers a promising strategy to enhance sustainability in urban transit systems. This study assessed solar irradiation along the tram route in Cuenca—an Andean city characterized by distinctive topographic and climatic conditions—with the aim of evaluating the technical feasibility of integrating solar energy into the tram infrastructure. A descriptive, applicative, and longitudinal approach was adopted. Solar irradiation was monitored using a system composed of a fixed station and a mobile station, the latter installed on a tram vehicle. Readings carried out over fourteen months facilitated the analysis of seasonal and spatial variability of the available solar resource. The fixed station recorded average irradiation values ranging from 3.80 to 4.61 kWh/m²·day, while the mobile station reported values between 2.60 and 3.41 kWh/m²·day, revealing losses due to urban shading, with reductions ranging from 14.7% to 18.8% compared to fixed-site values. It was estimated that a fixed photovoltaic system of up to 1.068 MWp could be installed at the tram maintenance depot using 580 Wp panels, with the capacity to supply approximately 81% of the annual electricity demand of the tram system. Complementary solar installations at tram stops, stations, and other related infrastructure are also proposed. The results demonstrate the technical feasibility of integrating solar energy—through fixed and mobile systems—into the tram infrastructure of Cuenca. This approach provides a scalable model for energy planning in urban transport systems in Andean contexts or other regions with similar characteristics. Full article

Agrivoltaics (APV) mitigates land-use competition between photovoltaic installations and agricultural activities, thereby supporting multifaceted policy objectives in energy transition and sustainability. The availability of organic residuals from agrifood practices may also open the way to their energy valorization. This paper examines a small-scale farm in the Basilicata Region, southern Italy, to investigate the potential installation of an APV plant or a combined APV and bioenergy system to meet the electrical needs of the existing processing machinery. A dynamic numerical analysis is performed over an annual cycle to properly size the storage system under three distinct APV configurations. The panel shadowing effects on the underlying crops are quantified by evaluating the reduction in incident solar irradiance during daylight and the consequent agricultural yield differentials over the life period of each crop. The integration of APV and a biomass-powered cogenerator is then considered to explore the possible off-grid farm operation. In the sole APV case, the single-axis tracking configuration achieves the highest performance, with 45.83% self-consumption, a land equivalent ratio (LER) of 1.7, and a payback period of 2.77 years. For APV and bioenergy, integration with a 20 kW cogeneration unit achieves over 99% grid independence by utilizing a 97.57 kWh storage system. The CO₂ emission reduction is 49.6% for APV alone and 100% with biomass integration. Full article

By employing computational fluid dynamics (CFD) software (Ansys Fluent), we examined the thermal effects of vertical solar panels on the south-facing facades of mid-rise (50 m) and high-rise (100 m) buildings in a 5 × 5 idealized urban environment. Four configurations were analyzed in this study: no installation, evenly distributed, concentrated, and panels on both sides. Vertical solar panel installations were affected by building temperatures and pedestrian-level thermal environments. In the leeward streets of central buildings, pedestrian-level temperatures progressively increased by row, with the even distribution showing significant heat accumulation. For 100 m buildings, the average temperature under the even distribution configuration increased from 35.6 °C (no panels) to 39.5 °C (a difference of 3.9 °C, approximately 10.96%). Full article

Facing the severe challenge of global warming, the construction of photovoltaic (PV) power stations has been increasing annually both in China and worldwide, with mountainous areas gradually becoming preferred sites for such projects. Mountain landscapes are ecologically sensitive, and the large-scale installation of PV panels may lead to destruction of the mountain landscape ecological environment. In this study, soil physicochemical properties were measured in 160 soil test plots, and vegetation community conditions were assessed in 26 vegetation test plots at a mountain PV power station in Damiao Town, Chaoyang County, Liaoning Province, China, using a combination of field sampling and laboratory testing. Based on mean values of 15 soil and vegetation indicators under different PV panel coverage rates, calculated via ANOVA in SPSS 27.0 software with Bonferroni-corrected p-values, the effects of various coverage rates on the mountain landscape ecological environment were investigated through multiple comparisons of the mean values. Using the Euclidean distance principle, the similarity ranking between the ecological environment under different PV coverage intervals and the control point was determined as follows: 0% > 0–5% > 15–20% > 5–10% > 10–15% > over 20%. Ultimately, considering the power generation requirements of the PV power station, the 15–20% PV panel coverage rate was identified as the optimal range that minimizes impact on the mountain landscape ecological environment while meeting electricity production demands. Therefore, construction stakeholders should fully consider the influence of PV panel coverage rate on the mountain landscape ecological environment and control the coverage within the 15–20% range according to the power generation needs of mountain PV power stations, so as to mitigate the environmental impact of PV panel installation. Full article

Many existing reinforced concrete (RC) frames with brick infill walls are vulnerable to earthquake damage, particularly when the walls contain window openings that reduce the lateral resistance. This study aims to examine the seismic performance of RC frames strengthened with U-shaped precast concrete (PC) wall panels. In the proposed method, the window-containing brick infill walls within the RC frames are replaced with factory-fabricated U-shaped PC wall panels, thereby converting the infill into a strong and rigid structural element while preserving the openings. The panels are anchored to the RC frame using post-installed anchors inserted through predrilled holes, allowing for rapid and secure installation with minimal on-site work. To validate the method, five full-scale, one-bay, one-story RC frames were constructed and tested under reversed cyclic lateral loading. Three frames were strengthened with U-shaped PC wall panels of varying thicknesses and large openings. Displacement-controlled cycles following ACI 374.1-05 (R7.0) were applied, with three cycles at each drift ratio stage, and no axial load was applied to the columns. Compared with the reference specimen with a U-shaped brick wall, the strengthened frames exhibited up to 3.29 times higher lateral strength, 4.39 times higher initial stiffness, and 4.33 times greater energy dissipation capacity. These findings demonstrate that the proposed strengthening technique significantly enhances seismic resistance while maintaining the architectural openings, offering a practical and efficient solution for upgrading low-rise RC buildings. Full article

Land availability constraints limit the installation of conventional ground-mounted solar installations. As a result, Floating Photovoltaic (FPV) systems are gaining popularity as an alternative to renewable energy generation. FPV consist of individual solar panels that are commonly symmetrical and modular. However, the hydrodynamic behaviour of FPVs in water surface waves is understudied to ensure their stability and optimal performance under varying environmental conditions. This literature review examines various modelling techniques applied in studying FPV hydrodynamics. Specifically, the application of Computational Fluid Dynamics (CFD) solvers and potential flow theory solvers is investigated for their effectiveness in capturing the behaviour of FPVs and mooring dynamics under the impact of wind and waves. The review highlights the advantages and limitations of each approach. Findings suggest that a combined CFD-potential flow approach offers a perfect balance between accuracy and computational efficiency, offering valuable insights into the performance of FPVs. However, extensive research is notably absent in hydrodynamic modelling for large-scale FPVs. This lack of research represents a significant gap in our current study on multiscale FPV systems. Full article

Vertical axis turbines (VATs) have grown in popularity over the past decade, owing to their lower cost of energy (CoE) when installed in remote offshore locations. The Davidson Hill Venturi system, as a kind of vertical axis tidal turbine technology, has been tested and proved to increase the power generation by the effect from the venturi structure. Based on the Computational Fluid Dynamic simulation (Ansys 2021R1) software, the present project develops a complete and improved 3D model to calculate the influence from different parameter adjustments on the turbine. The angle of the hydrofoil on the side panel was investigated in a previous study, while the new hydrofoil and different number of blades on the centre rotor can also affect the power generation of the tidal turbines. With this accurately created design, a sizing procedure is developed, and several 3D turbine models with a new hydrofoil or different number of blades are established. Both three-dimensional and two-dimensional section results are compared with the model with adjusting parameters. The 2D section view obtained from a static 3D model without a centre rotor is used to compare with the previous research, while the different number of blades is simulated by the dynamic 3D model without the hydrofoil. An analytical optimisation demonstrates that the new hydrofoil GOE-222 performed better than the material used in a previous study. The optimal number of blades between four blades and eight blades for use in the DHV turbine is also confirmed to be four. Full article

Glacier retreat due to climate change is accelerating worldwide, yet the phenomenon remains abstract for many people, especially those unfamiliar with mountain environments. The Urban Glaciology experiment, conducted during Milan’s internationally renowned “Fuorisalone” 2024 design event, aimed to bridge this perceptual gap by simulating real glacier melt processes in a busy urban square. Three large ice blocks with contrasting surface conditions (i.e., clean, dirty, and debris-covered) were exposed to springtime urban temperatures, mimicking conditions found on Alpine glaciers during summer. Over one week, the blocks produced a total of 748 L of meltwater, with dirty ice melting up to four times faster than debris-covered ice, consistent with established albedo effects. These results confirmed the thermal analogy between Milan’s spring conditions (+15 to +20 °C) and the ablation season on Alpine glaciers. Visitors observed the differential melting in real time, supported by visual indicators, explanatory panels, immersive virtual experiences, and direct interaction with researchers and students. Informal interviews indicated that more than 60% of participants reported a perceptual shift, recognizing for the first time that urban temperatures can replicate glacier melting conditions. By embedding a science-based installation in a major cultural tourism event, the experiment reached a diverse, non-traditional audience—including tourists, designers, and citizens—and encouraged reflection on the implications of glacier loss. The success of this initiative highlights the potential of replicating similar models in other cities to raise awareness of environmental change through culturally engaging experiences. Full article

Domestic water heaters traditionally use natural gas or electric resistance to heat stored water. A gas water heater relies on a non-renewable resource, while an electric water heater might rely on electricity generated by a non-renewable resource. This study analyzes the performance of an electric water heater featuring a novel heating element design based on a positive temperature coefficient (PTC) material powered directly by solar photovoltaic (PV) modules in a northern latitude installation. The project analyzes the operation of two different design temperatures of the PTC heating elements (50 °C, and 70 °C) when fed by three solar PV panels during the spring in the high-latitude location of Anchorage, Alaska (61.2° N). Our results show that both design temperatures of the PTC heating elements are able to achieve self-regulation at a sufficient and safe operating temperature for a domestic use case. Analysis of water heater performance directly connected to PV power showed that the PTC-equipped water heater had a limited period of heating when sufficient solar irradiance is available. Because of this, restrictive use of the water heater might be necessary during periods of non-daylight hours to preserve hot water in an insulated tank. However, this PV-to-PTC setup could be effectively used in industrial, commercial, and research settings. Full article

The integration of photovoltaic (PV) panels in greenhouses enables dual land use, combining crop production with electricity generation. However, PV installations can reduce both the intensity and uniformity of light at the canopy level, potentially affecting crop growth. This study employed computational fluid dynamics (CFD) simulations to evaluate the effects of different layouts of commercial-size thin PV modules—both opaque and semi-transparent—installed at gutter height in greenhouses on irradiance and, in particular, on its distribution within the greenhouse. Achieving a homogeneous distribution of light is critical for effective plant growth beneath photovoltaic systems. The influence of greenhouse size and roof shape on the intensity and uniformity of visible radiation was investigated as well. The results showed that during winter (21 December), irradiance in a mono-span tunnel greenhouse was 4–6% higher than in a multi-span large structure; in summer (21 June), this difference increased to 10–13%. Among the opaque PV layouts tested, the north–south (NS) straight-line arrangement provided the most uniform light distribution, outperforming the checkerboard and east–west (EW) layouts. The EW straight-line layout was the least effective regarding light uniformity. Roof shape (arched vs. pitched) had minimal impact on radiation distribution. Semi-transparent PV modules consistently resulted in 17% higher irradiance and more uniform light distribution than opaque ones. These findings can inform efficient PV deployment strategies in greenhouses to enhance both energy yield and crop productivity. Full article

This study investigates the asymmetric trade-off between cost and reliability in the optimal sizing of stand-alone Hybrid Renewable Energy Systems (HRESs) composed of photovoltaic panels (PV), wind turbines (WT), battery storage, a diesel generator (DG), and an inverter. The optimization is formulated as a multi-objective problem with Cost of Energy (CoE) and Loss of Power Supply Probability (LPSP) as conflicting objectives, highlighting that those small gains in reliability often require disproportionately higher costs. To ensure practical feasibility, the installation roof area limits both the number of PV panels, wind turbines, and batteries. Two metaheuristic algorithms—NSGA-II and MOPSO—are implemented in a Python-based framework with an Energy Management Strategy (EMS) to simulate operation under real-world load and resource profiles. Results show that MOPSO achieves the lowest CoE (0.159 USD/kWh) with moderate reliability (LPSP = 0.06), while NSGA-II attains a near-perfect reliability (LPSP = 0.0008) at a slightly higher cost (0.179 USD/kWh). Hypervolume (HV) analysis reveals that NSGA-II offers a more diverse Pareto front (HV = 0.04350 vs. 0.04336), demonstrating that explicitly accounting for asymmetric sensitivity between cost and reliability enhances the HRES design and that advanced optimization methods—particularly NSGA-II—can improve decision-making by revealing a wider range of viable trade-offs in complex energy systems. Full article