Photovoltaic Collector Research Articles

Assessment of Flat, Symmetric, and Asymmetric CPC Photovoltaic Thermal Air Solar Collectors for Building Façades Using Artificial Neural Network Modelling

Assessment of Flat, Symmetric, and Asymmetric CPC Photovoltaic Thermal Air Solar Collectors for Building Façades Using Artificial Neural Network Modelling

Bridging the gap: A comparative analysis of indoor and outdoor performance for photovoltaic-thermal-thermoelectric hybrid systems

This research evaluates the performance of a hybrid thermal-thermoelectric photovoltaic air collector system (PV/T-TE) through experimental investigations. By integrating photovoltaic (PV) panels with thermoelectric (TE) modules, the system aims to enhance efficiency and energy output by converting waste heat into additional electricity. The study examines the impact of radiation intensity, ranging from 455.65 to 795.18 W/m2, on the system's performance, utilizing output temperature (To) and plate temperature (Tp) as key metrics. Managing waste heat in PV technology remains a challenge, impacting efficiency. Traditional PV/T systems generate both electricity and thermal energy but suffer efficiency losses due to inadequate heat management. Integrating TE modules into PV/T systems offers a promising solution, but optimal configurations and performance impacts under varying conditions are underexplored. Limited research focuses on PV/T-TE hybrid systems, with most studies addressing PV-TE systems. The objectives of this research are to experimentally assess the impact of integrating TE modules on the thermal and electrical efficiency of PV/T systems under varying radiation intensities and air mass flow rates. The methodology involves setting up a PV/T-TE hybrid system, conducting experiments under controlled conditions, and analyzing key performance metrics. The study explores optimal TE module configurations and installation techniques to maximize heat transfer and electricity generation. Comparative analysis with conventional PV/T systems establishes the superiority of the hybrid system. Findings indicate significant benefits from incorporating TE modules, enhancing energy output and efficiency by maintaining optimal PV panel temperatures.

Optimization of coupling phase-change materials and thermal screens in façade-integrated hybrid photovoltaic collectors for optimal energy production and thermal comfort in buildings

The operation of building-integrated photovoltaic (BIPV) systems gives rise to a significant proportion of the solar radiation absorbed by the cells being unable to be converted into electricity. This phenomenon consequently increases the temperature. This temperature increase impacts the cells' electrical efficiency, leading to a reduction in their performance and accelerating their degradation. The combination of phase-change materials with insulating fluid blades, situated behind photovoltaic cells, represents a passive cooling solution that optimizes the performance of hybrid photovoltaic systems when incorporated into facades. The present study assesses a system that incorporates paraffin as a PCM and an argon layer in a PV-PCM-argon layer physical model (PVT/ArPCM), in comparison with a PV-PCM system (PVT/PCM), to enhance the thermoelectric performance of photovoltaic systems mounted on façades while ensuring optimal thermal comfort within buildings. The discrete heat transfer equations were solved using the Thomas algorithm and the iterative Gauss-Seidel method in conjunction with the implicit finite difference method. The findings illustrate that the electrical efficiency experienced only a slight increase, estimated at 0.01%, while there was a notable enhancement in the indoor thermal comfort experienced by occupants, with a 65% improvement observed due to the incorporation of an argon-filled thermal screen. The incorporation of an argon layer led to a minor reduction in temperature of 0.01°C in the photovoltaic cells, resulting in a minimal improvement of 0.014% in electrical power production. The phase-changing material incorporated into PVT/ArPCM demonstrated superior thermal management capabilities in comparison to the same material employed in PVT/PCM.

Wall Shading Losses of Photovoltaic Systems

The deployment of photovoltaic (PV) systems on rooftops in urban environments may encounter shading on the PV collectors from surrounding walls, acting adversely on the generated electricity of the PV systems. Most studies on the shading of PV systems do not deal analytically with the shading losses of PV collectors affected by walls, fences, and obscuring objects. The present article mathematically formulates shadow expressions for wall and inter-row shading on PV collectors and calculates the percentage of annual shading losses affected by wall heights and azimuth angles, the distances of walls to collectors, and the length and azimuth angles of collectors. This study indicates that the shading losses increase for shorter distances from the collector to the walls and for higher walls. Shading losses may reach 7 percent for wall heights of 4 m and at a distance of 2 m from the collectors to a wall. The results indicate that wall shading dominates inter-row shading.

Achieving net zero energy penalty in post-combustion carbon capture through solar Energy: Parabolic trough and photovoltaic technologies

The adoption of carbon capture systems presents a pivotal strategy for mitigating greenhouse gas emissions, notably carbon dioxide. Nevertheless, the substantial surge in energy consumption associated with such systems remains a significant challenge. Addressing this challenge necessitates the integration of renewable energy sources. This study is dedicated to optimizing the conventional post-combustion carbon capture configuration, focusing on energy, exergy, and exergoeconomic considerations. The optimized configuration showcases a noteworthy 10 % reduction in overall energy penalties compared to its conventional counterpart, primarily attributed to diminished energy utilization in the reboiler. To achieve absolute sustainability and eliminate energy penalties in the optimized configuration, integration of a parabolic trough collector for steam provision to the reboiler and photovoltaic solar collectors for powering the plant’s equipment was undertaken. Furthermore, the incorporation of solar thermal storage tanks and batteries enables the storage of excess heat and electricity, ensuring operational continuity for up to 13 h in the absence of sunlight, such as during nighttime. The final optimized configuration manifests a commendable 14 % enhancement in exergoeconomic performance relative to the conventional configuration, thereby realizing zero energy penalties. This achievement renders the optimized configuration a compelling and viable choice for carbon capture units.

Performance Assessment of Hybrid PV/PVT Collectors Incorporating Natural Water-Cooling Circulation

The present work investigates outdoor recitals and characteristics of hybrid PVT collectors and compares using non-cooled Photo-Voltaic (PV) collectors on a clear day at Khamshet, Pune, India. The hybrid PVT is designed, fabricated, and mounted on the terraces of the institute to ensure maximum radiation will fall on PV and PVT collector. The spiral circular thermal absorber is manufactured and placed at the backside of the photovoltaic to lower the surface temperature by extracting heat through water flowing through the absorber. The experimentation is performed at 0.03 kg/sec of water and natural cooling circulation is adopted for experimental work. The uncertainty analysis is also performed to ensure the accuracy of the results. The investigation observed that the PVT collector is superior to the PV system from electrical and thermal efficiency viewpoints. The cutback in PV module temperature was observed in a variation of 8.7-13.7%, which justifies using the water-cooling technique. The maximum electrical and thermal efficiency of 6.93 % and 52.7% were found for PVT collectors while sole maximum electrical efficiency of 5.62 % was found for PV collectors. This study concludes that the PVT collector has better performance characteristics than the PV collector and can be further enhanced using different fluid and thermal absorber designs.

Energy-efficient solar heat supply system based on hybrid photovoltaic collector

Following the commitments made under the Paris Climate Agreement, the scientific community has initiated a strategic increase in the share of renewable energy sources while gradually reducing dependence on traditional carbon fuels. Priority is given to the acceleration of the development of the photovoltaic industry, which has shown a constant increase in capacity over the past decades. According to the energy and climate strategies of the European Union, a significant increase in the amount of energy generation due to solar sources is planned. Therefore, the article is devoted to the development of a solar heat supply system based on a hybrid thermal photovoltaic solar collector with an improved design and analysis of the main characteristics of its operation using computer modeling. The authors have developed a 3D computer model of the proposed hybrid system with a solar collector by using SolidWorks software. The change in the temperature of the heat carrier in the hybrid thermal photovoltaic solar collector under constant solar radiation was analyzed. The temperature change of the coolant in the thermal accumulator of the system was also investigated. The results of the simulation of thermal processes revealed the key regularities of the temperature increase during the computer experiment, both in the hybrid thermal photovoltaic solar collector and in the thermal accumulator. The change in the instantaneous specific heat capacity of the developed solar collector was analyzed, and its average efficiency was estimated. The trends of changes in the thermal efficiency of the developed heat supply system during the computer experiment were determined. The novelty of the study is that the design of the hybrid thermophotoelectric solar collector has been improved, its 3D computer model has been developed, and the main thermal characteristics of the developed heat supply system with constant solar radiation have been obtained, which will contribute to the development of calculation methods for such heat supply systems with hybrid solar collectors in the future.

Technical and economic assessment of hybrid PVT solar systems compared to independent solar thermal and photovoltaic collectors in high-temperature zones: A case study in Mexicali, Mexico

This study analyzes the technical and economic feasibility of hybrid photovoltaic/thermal (PVT) solar energy systems, comparing them with independent flat plate solar thermal collectors (FP) and photovoltaic (PV) modules. Using TRNSYS software, different configurations were simulated under the climatic conditions of Mexicali, Baja California, Mexico. The results indicate that, although independent FP and PV systems exhibit better energy performance in terms of energy production and solar fraction, PVT collectors offer higher specific global energy production (electrical + thermal). However, the economic feasibility of PVT systems is limited due to high investment and maintenance costs, coupled with the low cost of thermal and electrical energy in the study region. Independent FP and PV collectors also face similar economic challenges, with return on investment extending beyond the 20-year lifespan of the project. Additionally, the low thermal energy demand for domestic hot water in the studied region negatively impacts the efficient utilization of these systems. This analysis suggests that in contexts where available installation space is limited, PVT systems can be an efficient solution. However, in scenarios with sufficient space and high energy costs, energy generation with separate equipment remains more viable. Moreover, climatic conditions and DHW demand affect the efficiency of the systems. The discrepancy between solar energy generation and hourly DHW demand necessitates the implementation of TEST, which significantly increases costs and impacts the economic viability of the project.

Novel cooling system for free-standing photovoltaic panels

ABSTRACT Although photovoltaic (PV) technologies enjoy tremendous benefits and hold the huge potential to lower building overall energy consumption, there is a major drawback. PV efficiency is extremely sensitive to heat and significantly reduced by increasing setting temperature and solar irradiance; thereby, thermal management in PV collectors plays a significant role in generating electrical energy. Using oscillating heat pipes attached to the rear side of PV panels is considered a novel and useful approach to dissipating heat. In this study, a novel cooling system that consists of a newly designed spiral oscillating heat pipe is introduced, while DI water and 0.2 g/l graphene are used as working fluid and PV panels are located at tilt angles of 30° and 60°. The OHP efficiency is higher at 60°; however, the efficiency of PV is maximized at 30° since the panel is exposed to maximum solar irradiance. The research demonstrates that the cooling method proves highly effective, especially in the hottest time of the day and the power output improves considerably from 38 W to more than 42 W at 30°, while the value is about 39.7 W when water is used as a coolant.

Improved Land Use Efficiency Through Spectral Beam Splitting in Agrivoltaic Farms

Installing photovoltaic (PV) collectors above arable land (Agrivoltaics) can aid with the shortage of available land area for solar power generation and food production. Most open field agrivoltaics are based on opaque PV devices which absorb photosynthetically active radiation (PAR, 400-700 nm), reducing crop yield and increasing variability in light distribution across the field. This research evaluates the performance of spectral beam splitter integrated photovoltaic (BSIPV) modules using a PV performance model. A high percentage (66 %) of PAR incident on the spectral beam splitter is transmitted effectively to the plants, while the near infrared radiation (NIR, > 700 nm) is reflected to the adjacent bifacial opaque photovoltaic module to generate power. In the model, seven rows of modules were placed uniformly across the field at a height of four meters from the ground. Considering a cool season (November – March) in Yuma, Arizona, in a conventional opaque PV agrivoltaic farm received 43 % lower total daylight integral (TDLI) across the season in comparison to open field with a coefficient of variation (ratio of standard deviation to mean expressed in percentage) of 56 % in TDLI across the field. On the other hand, the BSIPV agrivoltaic farm limited the drop in TDLI to 7 % in comparison to open field and the coefficient of variation to 14 % across the field. Thus, BSIPV showed a 36 % improvement in TDLI relative to the conventional opaque PV agrivoltaic farm. The results of the current study justify further research on the proposed collector concept.

Comparative Numerical Energy and Performance Analysis of Solar Photovoltaic and Solar Thermal Power Generation

This study analyses fixed and tracking solar photovoltaics and, solar thermal power. Performance in different locations was analysed for each configuration and technology using simulations based on a Typical Meteorological Year data. The study analysed a 25MWp solar photovoltaic and solar thermal power plants in each of the eleven selected locations in Zimbabwe. The performance of the solar photovoltaic and solar thermal power plants under different meteorological variables were assessed for all the selected locations. It was shown that different configurations together with different technologies have different conversion efficiencies. A high solar thermal conversion efficiency was found to be 18.718% in Gweru while it was 15.502% for solar photovoltaics in Mutare. The study also showed that highest insolation and clearness index values were found in Gweru. The average energy generated by the fixed photovoltaic collectors, tracking photovoltaic collectors and the Concentrating Solar Power plant were respectively 47.38GWh, 68.18GWh and 192.86GWh. There was a maximum percentage difference in the LCoE generated of 32.03% between the fixed PV collectors and the Concentrating Solar Power plant and a difference of 4.74% was realised between the tracking photovoltaics and Concentration Solar Power.

4E assessment of all-day clean electricity generation systems based on green hydrogen integrated system using PV and PVT solar collectors and wind turbines

Green hydrogen production powered by renewable energy sources is critical to the global transition to sustainable energy and net-zero emissions economies. The current study explores the multifaceted potential of green hydrogen as a key player in creating a sustainable and carbon-neutral energy landscape for electricity production under five different renewable-based configurations. This study aims to provide a complete assessment (energy, exergy, economic, and enviroeconomic) of all-day clean electricity generation systems containing integrated green hydrogen systems, comprising Polymer Electrolyte Membrane (PEM) water electrolyzers and fuel cells and using several different clean power sources, such as Photovoltaic (PV) and Photovoltaic/Thermal (PVT) solar collectors and Wind Turbines (WT). The main studied system configurations include: i) PV-Electrolyzer-Fuel cell, ii) PVT-Electrolyzer-Fuel cell, iii) WT-Electrolyzer-Fuel cell, iv) hybrid (PV + WT and PVT + WT)-Electrolyzer-Fuel cell. A MATLAB/Simulink code has been built to simulate these systems under the climatic conditions of two solar and wind-dominant locations in Egypt. The results revealed that the required amount of electricity to produce hydrogen ranges from 56.17 kWh/kgH2 to 56.87 kWh/kgH2. The total energy and exergy efficiencies are up to 35% and 17%, respectively. Moreover, the minimum values of LCOE, LCOH, and LCOEFC are 0.028 $/kWh, 2.84 $/kg, and 0.253 $/kWh. Finally, the total amount of carbon dioxide mitigation is calculated.

Analysis of the energy efficiency of a system with a hybrid solar collector and thermal energy storage

The object of research is heat transfer in a hybrid thermal photovoltaic solar collector. International agreements and strategies aimed at combating climate change and reducing greenhouse gas emissions strongly call for the active implementation of renewable energy sources on a global scale. A special emphasis is placed on the development of solar energy, which has significant growth potential due to the constant improvement of technologies and cost reduction of production. With this in mind, the authors focused on the development and analysis of a computer model of an innovative hybrid system that effectively combines a solar collector for the simultaneous production of both thermal and electrical energy. The research included a detailed study of the temperature changes of the heat carrier in the hybrid photovoltaic solar collector and thermal accumulator during the period of solar irradiation. Thanks to careful monitoring, the main patterns of gradual temperature increase in both key components of the hybrid system were established. In addition, an assessment of the dynamics of changes in the instantaneous thermal power of the solar collector under the influence of various factors, such as the intensity of solar radiation, the angle of inclination of the collector, wind speed, etc., was carried out. The results of computer modeling showed the average indicator of the efficiency of the entire hybrid system, as well as its variations during a certain time of operation. In addition, the change in the instantaneous specific heat capacity and the overall efficiency of heat energy generation by the hybrid photovoltaic solar collector were analyzed. Special attention was paid to the study of the dynamics of changes in the thermal efficiency of the entire system, as well as its ability to efficiently store thermal energy in a specialized battery. The comprehensive analysis made it possible to obtain the key thermophysical parameters of the developed hybrid system with a photovoltaic solar collector. This data is extremely important, as it will allow engineers and scientists to accurately calculate the potential performance and efficiency of such a system when it is put into practical use in the future. In general, the results of the study emphasize the promising development of hybrid solar collectors as one of the leading technologies in the field of renewable energy in the context of global challenges of climate change.

A Review of the Modeling of Parabolic Trough Solar Collectors Coupled to Solar Receivers with Photovoltaic/Thermal Generation

This paper is a summary of the last ten years of work on the study of parabolic trough collectors (PTCs) and compound parabolic collectors (CPCs) coupled to photovoltaic and thermal solar receiver collectors (SCR-PVTs). While reviewing the state of the art, numerous review papers were found that focused on conventional solar receiver collector (SRC) technology for solar thermal generation. However, there is a lack of review papers summarizing SRC-PVT hybrid technology for solar electric/thermal generation, which would be beneficial for researchers interested in this area of research. This paper provides a review of SRC-PVT hybrid technologies. The theoretical foundations for analyzing and modeling PTC and CPC concentrators coupled to SRC-PVT are described, with an emphasis on modeling through thermal resistances and energy balances. Additionally, this section provides a concise overview of previous studies that have addressed the modeling of PTC and CPC collectors coupled to SCR-PVT, as well as experimental information useful for the validation of new mathematical models of SRC-PVT.

Heat pipes and nanofluids utilization for cooling photovoltaic panels: an application of hybrid machine learning and optimization models

Abstract This study explores the synergies between advanced cooling technologies and photovoltaic systems, seeking to improve their overall efficiency and contribute to the broader goal of mitigating greenhouse gas emissions. To cool photovoltaic panels in more efficiently maner, understanding heat pipes, nanofluids, and panels interaction play key roles. For analysis and optimization, hybrid models of convolutional neural network (CNN) and firefly optimization algorithm are employed. The firefly optimization algorithm is used to optimize the thermosiphon heat pipe’s operational conditions, taking into account inputs such as the filling ratio, nanofluid concentration and panel angle. The study compared the predicted outcomes of a classic CNN model to laboratory experiments. While the CNN model was consistent with experimental findings, it struggled to predict high power values with precision. The proposed model improved high power value predictions by 4.05 W root mean square error (RMSE). The proposed model outperformed the classic CNN model for values greater than 50 W, with an RMSE of 3.95 W. The optimal values for the filling ratio, nanofluid concentration and panel angle were determined after optimization with the firefly algorithm. The research contributes to the advancement of renewable energy technologies and the optimization of photovoltaic panel cooling and energy production. Nanofluid with 1% mass concentration improves photovoltaic collector thermal efficiency due to its higher thermal conductivity coefficient. The photovoltaic collector’s electrical efficiency peaks in the morning, drops at noon due to temperature and radiation and recovers by morning. Electrical efficiency is best with nanofluid at 0.86%. Exergy efficiency closely matches electrical efficiency, with nanofluid at the optimal percentage achieving the highest efficiency and water cooling the lowest.

Economic dispatch of a bioclimatic office building considering thermal energy, electricity and water demands

Energy and otherresourcesmanagement in produc-tionsystems is a common topicin recent literatureas many envi-ronmental and economic issues are related to the efficient use of theirdevices. In this sense,conversion and storage models based oninput-outputbalances are helpful todetermine the combination of resources that allow tooperate a plantwith the lowest possible cost. This paperis aimed at analyzingthe optimal flows of re-sourcesthat would meet the demands of abioclimatic building,taking into accountthe characteristics of itsfacilities, which in-cludes both photovoltaic modules and solar collectors to produce self-consumption electric and thermal energy.The simulation re-sults for two different days of 2018have been included. They ver-ifythe validity of the proposed model, which could be extended for carrying out analyses on similar buildings, modelled as an en-ergy hub, in order to assess its optimality and proposing manage-ment policies.

Investigation of a new solar-wind energy-based heat pump dryer for food waste drying based on different weather conditions

To date, many studies endeavors have been undertaken regarding the provision of energy necessary for heat pump drying systems utilizing renewable energy resources. Conversely, the contemporary heat pump dryers require both electricity and heat concurrently, whilst the sporadic availability of a particular renewable energy source throughout the day necessitates the utilization of a combination of multiple renewable sources as a prospective remedy to these predicaments. The present research aims to assess the practicability of integrating photovoltaic and thermal collectors with wind turbines for the purpose of meeting the energy demands of a food waste drying system. A study was conducted to evaluate the performance of a dryer with a fixed weight of 100 kg and a moisture removal rate of 71.42 kg/h under varying climatic conditions in the cities of St. Petersburg, Yekaterinburg, Yakutsk and Khabarovsk, Russia. The investigation took into account four key factors, specifically energy, exergy, economy, and environment, over a period of one year. The thermodynamic outcomes derived from economic considerations indicate that an increase in dryer usage leads to a decrease in energy efficiency and a rise in energy expenditure. According to the empirical data, the optimum utilization of the dryer was recorded in Khabarovsk urban center as a consequence of the favorable climatic milieu which facilitated an efficacious moisture extraction rate of 51850.92 kg/year. Conversely, the city of Yakutsk demonstrated the lowest utilization frequency of the dryer, attributable to the unfavorable atmospheric conditions which hindered an effective moisture extraction rate, recording a minimal usage frequency of 27996.64 kg/year. The production of clean electricity and avoidance of natural gas for heating purposes in the cities of Khabarovsk and Yakutsk resulted in the attainment of the most pronounced decreases in carbon dioxide emissions, as indicated by the recorded figures of 47.53 tons and 25.32 tons, respectively. Consequently, following an economic evaluation pertaining to optimal repayment time, based on an interest rate of 0.03 %, the cities of St. Petersburg, Yekaterinburg, Yakutsk and Khabarovsk demonstrate repayment periods of 12.9, 12.6, 18, and 9.6 years, respectively.

Performance analysis of a photovoltaic thermal-thermoelectric cooler air collector integrated with a mixed-mode greenhouse solar dryer

Performance analysis of a photovoltaic thermal-thermoelectric cooler air collector integrated with a mixed-mode greenhouse solar dryer

Optimal size and position of the planar back reflector moveable only in the direction normal to the bifacial solar collector plane

In this paper, the concept of a collector-reflector system consisting of a bifacial solar collector and a single flat-plate reflector separated and placed in parallel below the collector but moveable only in the direction normal to the collector plane is investigated. The developed mathematical model was used to optimize the size and position of the planar back reflector. The optimal hourly, daily, monthly and annual distances between the collector and reflector were determined. In addition, the daily, monthly and annual energy performance of the optimized bifacial collector-reflector system was estimated and compared with that of the corresponding monofacial solar collector. Based on the obtained results, two ways of use of the reflector are recommended, either according to the optimal hourly (moveable reflector) or optimal annual (fixed reflector) reflector positions. With optimally positioned moveable or fixed reflector the total solar radiation incident on the bifacial solar collector can be significantly higher than that for a monofacial solar collector. Its largest daily and monthly as well as average annual increase is: 74% (59%), 65.91% (46.21%) and 54% (39.4%), respectively. The proposed model can be applied to evaluate the energy performance of flat-plate bifacial thermal, photovoltaic or photovoltaic-thermal solar collector, of arbitrary size and position, which is in this arrangement with a planar reflector.

An open-loop hybrid photovoltaic solar thermal evacuated tube energy system: A new configuration to enhance techno economic of conventional photovoltaic solar thermal system

One inherent problem of the conventional hybrid photovoltaic solar thermal system is the gradual loss of module power efficiency with low energy harvesting due to steady increase in module temperature with repeated circulation of the cooling water as a result of its closed loop configuration. This poor energy harvesting couple with high initial investment has made investment in this technology unattractive. This study proposes an enhanced hybridisation of the Photovoltaic Solar Thermal System collector with an evacuated tube based on an open-loop cooling configuration and unique flow control strategy. The aim is to improve cooling of solar panel leading to higher energy harvesting and utilisation that improves economic viability that will promote faster adoption. A numerical model is formulated using TRNSYS 18 software to assess the techno economics of the hybrid system. The model is validated using the verification and experimental methods. Overall, the findings show that the enhanced hybridisation and flow control strategy has resulted in higher annual renewable power generation and utilisation by 10 % than the basic hybrid Photovoltaic Solar Thermal system. This has resulted in significant economic savings, cutting operating expenses by 48 %. The ability to tailor the intended use of the system to meet with hot water and electrical power demand of different residential building is another attribute of proposed system that improve its energy harvesting reducing it payback period and doubling it economic benefit hence promoting it fast adaptability.