Solar Photovoltaic Thermal System Research Articles

Energy, exergy and sustainability analysis of a photovoltaic-thermal solar system with nano-enhancement and thermal energy storage integration

As a result of using various energy sources such as fossil fuels, harmful gases emerge and endanger the world's future. The search for different energy sources is to diminish the dangers that may arise in the future. Renewable energy sources are also the most basic for a sustainable future. This study aims to increase the performance of photovoltaic thermal collectors (PVT), which are used to obtain thermal energy from solar energy and produce electrical energy. The novelties of this experimental work are the analysis of a combination of a solar air heater and thermal energy storage via a phase change material technology and surface modifications on absorber plates, including a nanotechnological amendment. Furthermore, the adverse impacts on the environment of the manufactured systems were taken into account with the help of such parameters as waste exergy ratio and sustainability index. Initially, PVT with a V-grooved absorber surface (V-PVT) was built. In the second stage, nano-enhanced V-grooved PVT (NE/V-PVT) was produced, in which the absorber plate was coated by graphene nanoparticles. Then, a thermal energy storage entity was mounted onto the system, and the V-grooved PVT with the thermal energy storage entity (TS/V-PVT) was developed. 40 W absorber fans were used to provide airflow in these manufactured collectors. In addition, Styrofoam insulation material was used for the collector case, and a low-cost system was designed. Simultaneous experiments for each PVT were carried out. The waste exergy ratio (WER) and the sustainability index (SI) were also considered. Based on the experimental results, thermal efficiency was calculated as 40.60%, 54.01%, and 53.90% for V-PVT, NE/V-PVT, and TS/V-PVT, respectively. Furthermore, the coefficient of performance (COP) values were obtained as 2.67 for V-PVT, 4.28 for NE/V-PVT, and 3.49 for TS/V-PVT. The findings illustrated that nano-coating and V-grooved modifications on solar collectors substantially increased the system performance.

Experimental and economic evaluation on the performance improvement of a solar photovoltaic thermal system with skeleton-shaped fins

At elevated ambient temperatures, the production and efficiency of solar panels are degraded due to the overheating of the cells. Cooling photovoltaic cells at elevated ambient temperatures can prevent overheating, extend their life, and enhance overall efficiency, particularly in areas exposed to strong sunlight and elevated temperatures. In this study, an attempt was made experimentally to increase the performance of solar photovoltaic thermal systems with a novel cooling technique. The proposed system has an absorber plate coupled with novel skeleton-shaped fins used to create double-pass ambient air channels below the solar module for natural heat dissipation. Performance of the proposed photovoltaic thermal system with skeleton-shaped fins was designed, evaluated, and evaluated, under different climatic conditions of the southern Algeria city of Ghardaïa from 8:00 am to 6:00 pm. Theoretical analysis was also developed relying on the energy and exergy balance equations for the system components. An economic analysis is also performed by the life cycle cost analysis to evaluate the feasibility, annual performance, and payback period of the proposed solar system compared with that of the conventional system. Results showed that the proposed photovoltaic thermal generates an average daily production of 2.02 kWh, which is 55.1 % more than the conventional system. The energy and exergy efficiency of the proposed system are higher than the conventional system by 8.61 and 8.98 %, respectively. The levelized costs of energy associated with the proposed system (0.17 $/kWh) is lower than that of the conventional system by 11.76 %. The payback period of the proposed system (6.21 years) is lower than that of the conventional solar systems by 34.7 %. This means that the additional power generation obtained by the proposed system with skeleton-shaped fins was sufficient to offset the total life cycle costs.

Performance of Photovoltaic Thermal and Biomass Gasification for Efficient Renewable Energy Generation: A Review

AbstractThis review presents the technical and operational performances of solar and biomass energy technologies viz photovoltaic thermal (PVT) and biomass gasification systems. This work aims to offer a reference and guidelines to the renewable energy‐related players, especially for those at the operational level and investors. This paper highlights the technical advantage of hybrid PVT with phase change material in terms of electrical and thermal efficiencies. While the operational performance of biomass gasification is thoroughly discussed via sensitivity analysis, the potential integration between solar and biomass gasification technologies is explored to complement and bolster the capabilities of both renewable systems within the power energy mix portfolio. Finally, few directions and significant takeaways considering the technical criteria are addressed for identifying efficient renewable energy generation.

Optimizing photovoltaic thermal solar systems efficiency through advanced artificial intelligence driven thermal management techniques

Photovoltaic Thermal (PV/T) solar systems have the capacity to convert solar radiation into both electrical and thermal energy. Solar cells convert solar radiation into electricity, whereas solar thermal collectors gather excess energy and use it to heat cooling fluids and extract leftover heat from photovoltaic cells. Optimizing the design of the PV/T cooling system is critical for increasing overall system efficiency. This research describes a revolutionary AI approach for determining the ideal design for PV/T cooling systems. The suggested system has three major stages: data collection (DC), data preprocessing (DP), and prediction (PS). In the DC step, the collected data is preprocessed before being input into the suggested prediction model. The PS uses the Optimized Deep Neural Network (ODNN) to forecast water, air, and electrical efficiency. To improve the model's effectiveness, a new met-heuristic method, the Sand Cat Swarm Optimization (SCSO), is used in conjunction with the Deep Neural Network (DNN). The SCSO approach improves the DNN's hyperparameters to maximize prediction accuracy. The results show that ODNN outperforms in terms of Mean Absolute Error (MAE), Mean Squared Error (MSE), and R-squared (R2), with values of approximately 0.0075, 0.00251, and 0.9972, respectively, demonstrating the effectiveness of the proposed AI-driven approach in optimizing PV/T cooling system design. In addition to predicting water, air, and electricity efficiency, the proposed AI-driven approach in this study shows the capacity to optimize the operational efficiency of a system. When combining SCSO with DNN, it shows its effectiveness in dynamically adjusting hyperparameters, contributing to the robustness of the model across many scenarios. Furthermore, the study focuses on the optimized PV/T cooling system's possible real-world applications, emphasizing its role in supporting sustainable energy solutions and solving the developing issues of solar energy consumption. The results confirm the suggested AI system's versatility and reliability, positioning it as a promising tool for improving solar energy technologies.

A novel concept of solar photovoltaic partial shading and thermal hybrid system for performance improvement

Large values from external causes, such as partial shade, can greatly influence output power of PV. The applications of partial shading are frequently utilized in simulation software. However, in this research work, partial shading and the integration of the photovoltaic Thermal (PV/T) Hybrid Solar Panel is implemented, and analysis is done to see how it affects the output power of solar panels under genuine climatic circumstances. Many research investigations have been conducted and researchers continue to look at PV/T systems to enhance their performance. The application is designed to provide information on solar panel output power under normal and partial shading situations. The maximum amount of power that solar panels can generate is 298.50 W. Under typical circumstances, partial shading in a solar panel can result in a maximum power value of 141.13 W, and this partial shading leads the power to increase.

Numerical Analysis of the Phase Change Material Impact on the Functionality of a Hybrid Photovoltaic Thermal Solar System in Transient Conditions

Numerical Analysis of the Phase Change Material Impact on the Functionality of a Hybrid Photovoltaic Thermal Solar System in Transient Conditions

Design and performance optimization of a novel zigzag channeled solar photovoltaic thermal system: Numerical investigation and parametric analysis

In order to overcome the drawbacks of traditional photovoltaic thermal systems, including their limited thermal power, low thermal exergy, and heat transfer fluid outlet temperature, it becomes essential to explore the optimal design configuration of the system for maximization both electricity and domestic hot water generation. Therefore, a detailed numerical modeling and comparative performance analysis on a solar photovoltaic thermal collector (PVT) are conducted under two novel structures of the cooling channels. The first system is a reference PVT collector with a classical straight zigzag-plated tube cooling channel (Case A), while the second PVT system proposes an innovative design of flow cooling channel which is divided into three equal zigzag-plated tube sections (Case B). Each section is also split into three double pass tubes and has a separate inlet and outlet in a staggered manner corresponding to the section that precedes and follows it. The two proposed PVT structures are investigated through computational fluid dynamic simulation under solar radiation values ranging from 200 to 1000 W/m2 and coolant flow rates varying between 0.001 and 0.005 kg/s using both water and air as coolant. The obtained results confirm the significant potential of the modified configuration (Case B) that yielded an improvement in the thermal efficiency by 7.23% and 15.75% for water-PVT and air-PVT system, respectively, over the reference PVT system (Case A). Also, the modified configuration (Case B) yielded an enhancement in the electrical efficiency by 4.0% and 4.6% for water-PVT and air-PVT systems, respectively. It can be concluded that dividing the cooling channel area into equally mini zigzag plate tube-shaped sections with multiple reciprocal entrances is regarded a feasible configuration for augmenting the performance of PVT collectors and maintaining a uniform coolant flow and reduced temperature distribution over the entire panel.

Solar photovoltaic-thermal system with novel design of tube containing eco-friendly nanofluid

In photovoltaic (PV) solar systems, electricity can be produced from part of the sunlight and the remaining energy raises the temperature. The aim of the current investigation is to suggest a novel design for the heat transfer tube's (HTT) cross section for overcoming this challenge in photovoltaic/thermal (PVT) systems. In this numerical simulation, the range of fluid inlet velocity (Vin) was set between 0.01 and 0.18 m/s. The value of ambient temperature (Tamb) and fluid inlet temperature (Tin) is 30 °C, and solar radiation (G) has been adjusted to 800 W/m2. A comparison was made between the circular tube and the 8-lobed tube with the same hydraulic diameter, and the better performance of the 8-lobed tube was proved. To meet the increased efficiency of the PVT system, copper fins with four different arrangements were employed. The highest efficiency occurred when the fins were placed all around the inside of the HTT. To create heat transfer fluid (HTF), non-toxic graphene nanoplatelets (GNP) have been mixed with water involving two weight fractions (0.025 % and 0.1 %). Examining the effect of changing the fluid inlet velocity (Vin), it was concluded that the system's electrical performance is increased by 5.8 %, with rise of Vin, in the best case. By using the GNP nanoplatelets (0.1 %), at Re = 1611, the maximum exergy, electrical, and thermal performances of the unit were 15.32 %, 14.05 %, and 55.22 %, respectively, in the best case. In the best case, more carbon dioxide (about 7.1 Tons) can be reduced and the carbon credit is 5.5 % higher than that of base case. In addition, the payback period is less than 2 years in the best case with 18700$ profit in the 10th year.

Simulation for impact of nanofluid spectral splitter on efficiency of concentrated solar photovoltaic thermal system

Nanofluid filter has been applied in current research to boost the efficiency of a concentrated photovoltaic thermal (CPVT) module. Owing to tunable optical features of nanofluid and its greater thermal characteristics, it was utilized as spectral filter and cooling fluid in the present proposed solar system. The mixture of silver and water has been utilized as working fluid and its concentration within the filter and cooling duct are 0.005 and 0.05, respectively. Three dimensional models have been proposed involving spectral distribution of solar irradiation. Also, transmissivity of nanofluid filter has been derived according to empirical models. Two structures have been applied for cooling duct: 1) straight bottom wall; 2) wall with triangular obstacles (semi-wavy wall). As velocity of nanofluid within the filter (Vf) section enhances, the electrical performance increases about 3.4 %. For case 4, with augment of concentration ratio (CR) from 3 to 30, the electrical performance reduces about 13.57 % while thermal performance augments about 5.68 %. When CR=10, utilizing case 4 makes electrical and thermal performance to enhance about 25.09 % and 22.36 % in comparison to case 1. Also, cell temperature decreases about 47.82 % with applying the filter within the second structure of the cooling duct.

Artificial neural network simulation and development of a predictive model to anticipate performance of a hybrid plant combined with PVT solar system

This article uses the neural network method and numerical data for predicting the performance of an integrated energy system. The studied system is an integrated energy system consisting of a gas turbine with an air preheater and subsystems such as the Kalina cycle, supercritical carbon oxide cycle and hydrogen production. In this unit, a photovoltaic thermal (PVT) module has been used to generate electric power, as well as heating and starting the organic Rankine cycle. In addition, a Proton exchange membrane (PEM) electrolyzer to produce hydrogen is integrated. To propose a model that can predict the behavior of the integrated system by changing the parameters, the important outputs of the system such as energy efficiency, exergy efficiency, exergy destruction rate and net output power have been extracted in the form of functions according to the input parameters namely T11, P11, P18, Rp. The results show that the suggested functions of four outputs have the acceptable value for mean square error and regression coefficient which show high accuracy. The influence of each variable on each other and their interaction on the responses are drawn and adequately explained using three-dimensional response surface diagrams. The analysis represented that the amount of exergy destruction in the high-pressure ratio is at its maximum value with the increase in the temperature of point 4. In addition, it is at its maximum value in the high-pressure ratio with different changes in the pressure of point 11. Generally, the p-values for predicted values less than 0.001 represent that the model is statistically considerable at the 99 % confidence level. The p-values for suggested functions show a high level of confidence.

Simulation of photovoltaic thermal solar system with new technique for improving electrical performance

Simulation of photovoltaic thermal solar system with new technique for improving electrical performance

Load Frequency Control With Renewable Energy Sources Using Practical Swarm Optimization Based On PID

Future competitive solutions for the production of electricity may be provided by emerging renewable energy sources (RESs) technologies as wind, solar photovoltaic, and solar thermal power systems. In this study, simulation tests have been conducted on autonomous hybrid generating systems(HGSs) made up of diesel engine generators (Degs), fuel cells (FCs), wind turbine generators (Wpg), solar photovoltaic generators (Pvpg), battery energy storage systems (Bess), and flywheels (Fess). The abrupt fluctuations in load, generation, or both cause the power system's frequency to vary. PID controller tuning using particle swarm optimization (PSO) is used for the optimization of controllers’ gains of the proposed hybrid systems. The proposed method is compared with a genetic algorithm (GA) and a traditional PID controller. To test the proposed controller, three different scenarios were used: first, changing the load's value with a fixed value over a set period of time; second, changing the load's value with variable values; and third, changing the load's value with a variable value while changing the system parameters. The simulation results reveal that the suggested controller performs better and is more resilient against load and generational disruptions by reducing the maximum overshoot value and settling time by 70% and 65%, respectively, and by 14.2% and 5% when compared to a GA-PID control.

Enhancement of photovoltaic module performance using passive cooling (Fins): A comprehensive review

Photovoltaic-thermal (PV/T) technology, combines the benefits of both solar photovoltaic (PV) and solar thermal systems into a single integrated solution. It is a promising renewable energy technology that maximizes solar energy utilization and offers multiple benefits for sustainable power generation. A review and discussion of both active and passive thermal management solutions for PV technology is included in this paper. Using fins on the back of PV is the focus of this paper in terms of its design and performance parameters. Fins are used in air, fluid, nanofluid and PCM cooling PV/T systems. Installing them in these systems improves their performance and increases their electrical and thermal efficiency together in rate range between 8 and 10%. Furthermore, this article examines different approaches to designing and implementing systems, as well as how to optimize results, in addition to exploring potential problems and opportunities. Aiming at creating, manufacturing, utilizing, and potentially promoting high-performance photovoltaic-based technologies and systems which include fins are the purpose of this article.

Research on designated calibration method of fault sensor in photovoltaic thermal heat pump system based on fault detection and virtual calibration

With the increasingly serious global energy problem, clean energy sources such as solar energy have become the mainstream focus of development. Among these, solar Photovoltaic thermal (PVT) heat pump systems have promising prospects. However, incorrect data transmitted by sensors can significantly impact the operation and control of the entire heat pump system, leading to reduced efficiency. Given the specific nature of PVT heat pump systems, their internal sensors are prone to errors during operation. To address these challenges, the Autoencoder Virtual in-situ calibration (AE-VIC) is applied to PVT heat pump systems. Preliminary studies have shown that this method can effectively reduce systematic and random errors in sensors. However, the current AE-VIC method faces certain issues, including unclear calibration targets and inefficient calibration of multiple sensors simultaneously, making it difficult to implement in practical systems. In order to overcome the limitations, fault detection is integrated with AE-VIC. By combining the feature extraction capability of Autoencoder with a Softmax classifier, sensors with faults can be identified before the overall calibration process, making the calibration objective of the AE-VIC more targeted. Following fault detection, inputs of the AE model are optimized using the mRMR algorithm for the identified faulty sensors. This optimization alleviates the difficulty of calibration. Through validation with actual system, the improved method effectively diagnoses and locates faulty sensors, and subsequently calibrates them. After calibration, the sensor system error can be reduced by over 95%. The improved calibration method surpasses the original AE-VIC method in terms of both time and accuracy.

N ASSESSING THE EFFECTIVENESS OF HYBRID SOLAR COLLECTORS SCHEME INIRAQ'S ENVIRONMENT

An evaluation of the performance of the Iraqi environments in terms of electrical, thermal and exergy efficiency is introduced in this study. The research is carried out in May 2022, in the Baghdad metropolis. The extraction process of heat from the photovoltaic units which arises from the coolant liquid mass flow rate deem as an essential point. The experimental studies were implemented by absorbing heat energy behind from the photovoltaic cell's surface in insulated conditions and using a cooled water unit. The results indicated that at a mass inflow rate of 0.2 kg/sec, the maximum average total efficiency of the system was recorded 22%. As a result, it is advised that to reduce the payback interval, it is possible to design efficient solar photovoltaic–thermal systems to promote the whole system's efficiency and lower the payback interval.

Techno-economic evaluation of photovoltaic thermal system integrated with porous phase change materials: Case studies in China

This study aims to to develope a comprehensive mathematical model for predicting the performance, environmental impact, and economic viability of solar photovoltaic thermal (PVT) systems, with specific focus on the use of Porous Phase Change Material (PPCM) into a PVT system (PVT-PPCM) and its effect on the cooling cycle temperature throughout the year. The model was experimentally validated and implemented in Matlab to assess the performance of various systems, including PV-only, PVT, and PV integrated with PCM (PV-PCM). To determine the optimum melting point temperature for the PCM-based systems, a sensitivity analysis was conducted for different locations in China. The annual performance, CO2 reduction, discounted payback time (DPBT), and Levelized cost of energy (LCOE) were predicted for each system. Subsidy-free method was used for economic evaluation, which only shows system’s cost savings. In addition, it is worth noting that the maximum power output of each system was evaluated to be 1 MW. The results of the study showed that PVT-PPCM exhibited the highest annual power output of 1920 MWh and CO2 reduction of 30 tons/year, while the LCOE ranged from 0.02 to 0.58 CNY/kWh and the DPBT varied from 5 to 20 years across the case studies. The study also compared the Levelized cost of electricity (LCOEel) of PVT and PVT-PPCM with cases in UK and Spain, with the lowest LCOEel of PVT recorded in Kunming at 0.4 CNY/kWh.The significance of this study lies in its identification of the strengths and weaknesses of PVT system designs across different climates, highlighting areas for improvement. By providing insights into system performance, environmental impact, and economic feasibility, this research contributes to the advancement and optimization of PVT technology for sustainable energy applications.

A Comparative Assessment of Solar Photovoltaic Thermal (PV/T) System with Solar Photovoltaic (PV) System

A Comparative Assessment of Solar Photovoltaic Thermal (PV/T) System with Solar Photovoltaic (PV) System

Development and economic evaluation of a CPVT system with PHP cooling; An experimental study

In this paper, the experimental investigation of the performance of a concentrated hybrid photovoltaic thermal solar system is sought. Accordingly, there is a parabolic trough concentrator receiver that consists of three components: a triangular duct, photovoltaic cells covering the duct, and a three-turn PHP. The PHP cools down the photovoltaic cells efficiently and regenerates waste heat. The duct is filled with a heat transfer fluid surrounding the PHP’s evaporator. The condensation section of the PHP is located outside the solar concentrator. Using a one-axis polar mechanism, the concentrator tracks the sun from east to west. The system experiment setup was fabricated and tested outdoors in Tehran’s climate. Different heat transfer fluids, including Glycerine, Ethylene Glycol, and Calcium Chloride water mixture, were tested. Given the enhancement of PHP performance, a variety of working fluids were tested, including graphene oxide nanofluid/water, acetone, and pure water. The experiments showed that graphene oxide nanofluid/water mixture provided the highest thermal performance. With the use of graphene oxide nanofluid/water (as a working fluid) and glycerine (as heat transfer fluid), experiment results showed a decrease of 7.84 °C in PV temperature and a consequent increase of 21.85% in electrical efficiency in best condition. Furthermore, the provided cooling system recycles a maximum of is 190.4 kJ of thermal energy equivalent 52.5% thermal efficiency, increasing overall efficiency by 74.35%. Lastly, the IRR of 65.41%, PBT of 1.04 years, and LCOE of 1.84 $/kWh demonstrate appropriate financial profitability.

Using a solar photovoltaic-thermal system, and a new hydrogen liquefaction system based on the enhanced claud cycle, design and multi-objective optimization

According to research by the International Energy Agency, fossil fuels have met around 80% of the world's energy demands in recent years, which has increased CO2 emissions, which primarily function as greenhouse gases. The transition to more efficient energy systems that employ renewable energy sources, among other things, in order to reduce environmental issues and reduce our reliance on fossil fuels, is inevitable. Hydrogen fuels are reliable and available renewable resources since they are affordable and have the potential to produce net zero carbon emissions. This study will demonstrate a technique for using solar energy to generate electricity and liquid hydrogen. The benefits of the proposed system will be examined in comparison to both standard liquefaction systems and the fundamental systems that power and cool them. The fundamental variables that determine more effectiveness, cheaper cost, more liquid hydrogen generation, and less pollution will be examined, and then optimization to accomplish all of the objective functions at once will be covered. The findings indicate that the actual work consumption in the liquefaction cycle is calculated to be 54301 kJ/kg H2. Also, as solar panel size grows, the volume of liquid hydrogen increases by 37.5%, and the highest surface of the panels provides the maximum power, or 4550 kW. Additionally, the system has a 56.3% efficiency, 13 kg/s of liquid hydrogen, and a cost 15.1 $/GJ.

Evaluation of a solar photovoltaic thermal (PVT) system in a dairy farm in Germany

Livestock farms are a major contributor to CO2 emissions. The use of renewable energy sources (RES) is an important step to mitigate emissions from farms. This paper develops and evaluates a market-integrated, cost-effective, and case-sensitive RES solution for livestock farms. For this purpose, the dairy farm at LVAT-ATB in Germany; which includes three barns for milk production with a total area of 3950 m2, was considered. A solar PVT system is designed to most effectively use the heat recovery of the milk coolers and to use the thermal heat from the PVT system to lift the inlet temperature of an electric boiler (E-boiler) and reduce grid electricity consumption. The performance and monthly thermal output of the designed PVT system are evaluated using two different PVT collectors; Solarus (concentrated) and Dual Sun (flat plate). A preliminary analysis was performed to determine the PVT collector most suitable for the livestock farm here studied. The DualSun collector generated a higher electricity output than the Solarus C-PVT, however, the C-PVT was able to reach higher temperatures. Since the LVAT-ATB farm site included an existing heat recovery system, the integration point was carefully defined and a semi-automated system was incorporated to (1) use the heat from the heat recovery system as the inlet heat for the PVT system and (2), to use the PVT buffer tank as additional storage to store excess heat from the heat recovery system. Using this approach, a maximum amount of thermal energy can be stored. The PVT system would further raise the temperature from the heat recovery system and thus minimize the electricity consumption of the E-boiler. Furthermore, a draft layout of all the components and outdoor enclosure was presented. 24 Solarus PVT collectors running at mean temperature of 45 °C meet 16% of the annual hot water demand of the dairy farm by direct solar heat and this number of PVTs can supply up to 38% of hot water demand in summer months. The payback period for this system is less than 6 years and annual electrical energy utilization ratio and highest solar thermal fraction are 9.7 and 51.9%, respectively. Furthermore, 24 PVTs on an annual basis, generate slightly more than 4,200 kWh of electricity that can be used to offset electricity consumed by electric boilers in the LVAT farm.