Photovoltaic Phase Change Material Research Articles

Experimental study of a PV-PCM window under hot summer and warm winter climate

An energy-efficient PV-PCM (Photovoltaic-Phase change material) window is proposed in this study. During the day, a portion of the incident solar radiation is converted into electricity, while excessive heat from internal sources and solar radiation is stored within the PCM infill. At night, the stored heat can be released from the PCM. Unlike existing PV windows with PCM infill, the PCM is sealed in separate modules, allowing for easy adjustment or removal to better adapt to different weather conditions. In this study, the light, thermal and electrical performance of the PV-PCM window was tested in comparison with common clear glazing window, PV window and PCM-infill window under hot summer and warm winter climate.The experiment results demonstrated the ability of PV-PCM window in delaying and reducing the peak indoor temperature in hot summer. Compared with common clear glazing window, the peak temperature reduced by 8.67, 5.35 and 10.70 °C in the three days. Correspondingly, the indoor heat gains were reduced by 364.97, 265.96 and 301.10 kJ. SHGC of the proposed PV-PCM window was reduced to <0.30, whereas the U-value was reduced to <2.50 W/(m2·K). Compared with the PV window, more power generation were observed by PV-PCM window because of the cooling effect brought by the PCM module nearby. Whilst balancing thermal regulation, the daily power generations of the 0.36 m2 semi-transparent CdTe PV-PCM window were 548.33, 316.55 and 58.85 kJ.

Influence of Different Melting Points of Phase Change Material on Photovoltaic Phase Change Materials System Performance: An Energy, Exergy, and Environmental Point of View

The photovoltaic (PV) module extracts and converts solar irradiation energy into electrical power in a sustainable and renewable manner. The substantial upswing in the temperature of the PV panel occurs while conversion predominantly impacts its performance and reduces efficiency. To resolve this issue, three different organic phase‐change materials (PCMs), OM29, OM35, and OM42, are proposed for cooling the PV panel as a thermal energy storage medium. The energy and exergy performance of PV panels with and without PCM are compared through experimental investigation to study the influence of different melting points of PCM with reference PV system (PVr). It is identified that the average PV panel temperature can be significantly reduced by incorporating PCM materials (OM29, OM35, and OM4), which are 12.7%, 21.53%, and 17.71% lower than the PVr system. The average electrical efficiencies of PV‐PCM–OM29, PV‐PCM–OM35, and PV‐PCM–OM42 are 10.96%, 10.77%, and 11.66%, which are 4.07%, 6.38%, and 4.91% higher than PVr system. Similarly, the average exergy efficiency is 4.62%, 5.06%, and 5.57% higher. The incorporation of PCM (OM29, OM35, and OM4) as a cooling mechanism effectively mitigates the CO2 3.70, 5.67, and 4.46 tons of CO2 throughout its lifetime and contributes to the sustainable development goal 7.

An Opinion on Strategic Management, Economy and Implementation of Clean Energy Driven by Photovoltaic-Phase Change Materials System

An Opinion on Strategic Management, Economy and Implementation of Clean Energy Driven by Photovoltaic-Phase Change Materials System

Annual performance study and optimization of concentrated photovoltaic-phase change material system

Concentrated photovoltaic (CPV) has the superiority of high efficiency and low cost. But the waste heat generated in PV cell has great effect on its performance. To study and optimize the real time photoelectric conversion performance, a two-dimensional PV model was firstly established. The impacts of concentration ratio and PV temperature on efficiency were investigated, and the correlation was derived. Based on that, phase change material (PCM) was utilized to realize temperature control of PV cell and a three-dimensional transient model for CPV-PCM system was established. The impacts of geometric parameters on the transient and annual performance were evaluated under the real climate conditions. The results show that concentration ratio has significant impacts on both thermal and electrical performance, and there exists an optimal concentration ratio to maximize the PV efficiency. At last, the system structure was optimized by orthogonal experimental method with annual average efficiency as the target. The optimal parameters combination was derived with concentration ratio of 300, PCM layer height of 60 mm, and fin number of 7. The validation results show that after optimizing, the maximum PV temperatures in summer and autumn are reduced by 9.4 °C and 7.4 °C, respectively, and the annual average efficiency of the system is improved by 1.83%.

Numerical study of phase change material partitioned cavities coupled with fins for thermal management of photovoltaic cells

To enhance the temperature control capability of photovoltaic-phase change material systems, a strategy involving the combination of fins and partitioned cavities is employed to enhance the heat transfer process. Thermal performance of four cavity arrangements including a rectangular cavity, a partitioned rectangular cavity, a finned rectangular cavity, and a partitioned rectangular cavity with fins at two tilt angles of 90° and 45° are numerically evaluated. By employing a partitioned cavity with fins, the entire melting time can be reduced by a maximum of 8.9% compared to the baseline case. Moreover, the results show that the individual or simultaneous utilization of the partition and fins at an inclination angle of 90° can not only effectively reduce PV panel temperature but also improve temperature uniformity of the PV panel. Reducing the inclination angle to 45° prolongs the melting time, and this also reduces the temperature control performance for the majority cavity structures. Compared with the baseline case, the temperature of the PV panel can be reduced by up to 5.0 K, and the temperature uniformity can be increased by a maximum of 35.0%. The partitioned cavity coupled with fins has the best overall thermal performance among all structures.

Numerical investigation of the effect of fin height on the performance of a building-integrated photovoltaic-phase change material unit and application of soft computing method to predict the optimal system performance

A numerical study is done to analyze the effect of fin length on the performance of a building-integrated photovoltaic-phase change material (PV/PCM) unit. The results obtained for cases with different fin lengths (1, 2, 3 and 4 cm) are compared with the findings related to the finless case. The required simulations are conducted by using computational fluid dynamics technique and with the help of Ansys Fluent software. Validation of the numerical method is done through comparison with the experimental data available in the literature. It was found that with the increase in the length of the fins, the performance of the system first improves and then weakens, but the performance of the PV/PCM unit is always better than the finless unit. It was found that the optimal fin length is equal to 3 cm. Furthermore, the artificial neural network technique was used to develop a relationship for predicting the temporal changes of the PV panel efficiency of the finned PV/PCM unit. The correlation coefficient of the model was reported as 0.9906, which confirmed the acceptable accuracy of the model.

Effect of Cantor fractal fin arrangements on the thermal performance of a photovoltaic-phase change material system: An experimental study

Phase change materials (PCMs) could be utilized to regulate the temperature of photovoltaic (PV) panels, thereby enhancing electrical efficiency. However, the performance of PCMs is limited by their low thermal conductivity. A novel Cantor fin based on fractal theory is put forward in this study to be applied for thermal property enhancement in a PV-PCM system. An experimental investigation regarding the influence of structural characteristics and configurations on the performance of the PV-PCM system was implemented using lauric acid as the temperature control medium. The performance of Cantor fractal fins was compared to that of rectangular fins with an equal volume and a finless cavity. The experimental results indicated that the adoption of fins augmented the uniformity of temperature distribution during the melting process of lauric acid compared to the PV-PCM system without fins. It also enhanced the heat transfer rate from the PV panel to the PCM. Specifically, using Cantor fins resulted in a maximum wall temperature decrease of 9.1 °C. Generally, Cantor fins outperformed rectangular fins in terms of raising even temperature dispersion in the PCM, lowering the temperature of the PV panel, and enhancing wall temperature uniformity. Furthermore, as compared to the vertical configuration, the horizontal arrangement enhanced the PCM temperature uniformity and electrical efficiency despite decreasing the wall temperature uniformity.

Enhancing efficiency of PVT systems with finned PCM technology

An increase in solar panel temperature reduces panel electrical efficiency, necessitating efficient active and passive cooling methods. This study proposes the introduction of Phase Change Material (PCM) on the backside of the solar panel, along with extended fins. The experimental investigation focuses on utilizing extended surfaces known as Thermal Conductivity Enhancers (TCE) in the PV-PCM (Photo Voltaic - Phase Change Material) module. Two independent aluminum fin designs are considered to enhance the thermal conductivity (k) of the PCM, analyzing the influence of the surface contact area and material volume fraction on the PV surface temperature during the charging period of the Production Validation Test-Pulse Code Modulation (PVT-PCM) panel. The experimental results demonstrate that an array of longitudinal and lateral fins with an optimal thickness of 3 mm maintains a lower temperature gradient throughout the process, significantly reducing the surface temperature of the PV panel. Numerical simulations using ANSYS Fluent were conducted for both the lateral- and cross-fin configurations, showing good agreement with the observed experimental data. This study aims tofill this research gap by optimizing PV panel cooling through the selection ofthe fin geometry, size, shape, and PCM.

A novel heat sink for cooling photovoltaic systems using convex/concave dimples and multiple PCMs

• PV system integrated with convex/concave dimples and multiple PCMs is numerically studied. • The dimpled surface enhances the melting rate without changing the PCM mass. • The multiple PCMs improve the thermal and electrical performance of the PV system. • The highest performance occurs at (two-PCMs:15–5 mm) arrangement with 8 dimples. The operating temperature of a solar panel affects its electrical efficiency. As the temperature increases, the solar cell's ability to generate electricity decreases so cooling is required to improve its performance. In this study, a novel design of photovoltaic phase change materials (PV-PCMs) system is established. It consists of a separate convex/concave dimpled aluminum plate and multiple PCMs that act as a heat sink. In order to achieve longer thermal management of PVs, the PCMs were arranged along the heat flow direction according to the melting temperatures. The thermal and electrical performance of the PV-PCMs system was numerically analyzed at different inclination angles. The system was tested using different numbers of dimples (smooth, 6, 8, and 10 dimples) and multiple PCMs with different thicknesses (single PCM, two-PCMs:10–10 mm, two-PCMs:15–5 mm) to obtain the optimal design. The numerical model and the literature data agreed very well. The (two-PCMs:15–5 mm) arrangement with 8 dimples provides the longest uniform operating temperature duration and the highest PV electrical efficiency. The thermal management durations were 40, 30, and 25 min, during which the percentage decrease in PV cell temperature was 7.14, 4.65, and 2.22 % at an inclination angle of 90°, 60°, and 30°, respectively, compared to the smooth wall with a single PCM. The novel design is recommended for future modeling of the PV-PCMs system.

Impact of building integrated photovoltaic-phase change material panels on building energy efficiency improvement: a case study

ABSTRACT Integrating phase change material with building envelopes is recently considered one of the most reliable passive solutions to mitigate indoor temperature fluctuations, improving therefore indoor comfort. In addition, the integration of photovoltaics to combat the gradual increase in energy consumption is highly increasing to meet the growing demand for energy. Using phase change material to improve thermal and electrical performances of building integrated photovoltaic systems and to reduce incoming heat energy indoors, simultaneously, were performed. Interestingly, it is highly recommended to integrate the building integrated photovoltaic phase change material systems on inclined roofs in order to perform the phase change material as preferred through a cyclic process. The peak temperature of the inclined and vertical building integrated photovoltaic systems decreased from 70.5°C and 41°C to 41.4°C and 31°C, respectively. Hence, a drop in average indoor daytime temperature where the peak indoor temperature has been reduced to about 4.5°C. The inclined and vertical building integrated photovoltaic systems’ DC power output, at midday, has been increased from 74.5 W to 108.5 W and 37.5 W to 38.5 W. Eventually, the use of phase change material decreased the thermal load leveling by 7%, 2% and 1.5% during the first three days, respectively, After the third day, the decrease of the thermal load leveling remained constant at 3%. Consequently, findings reveal that using phase change material could be an excellent solution to decrease indoor air temperature fluctuation and can bring higher temperature drops.

Analysis of the effects of porous media parameters and inclination angle on the thermal storage and efficiency improvement of a photovoltaic-phase change material system

The heat generation in the photovoltaic (PV) panels leads to the rise in temperature, which subsequently deteriorates the electrical efficiency of PV panels. The application of phase change materials (PCM) can reduce the operating temperature and perform as a cooling mechanism. However, the cooling performance and energy storage capacity of PCM are drastically affected by its poor thermal conductivity. Therefore, in this paper, the impact of the insertion of metal foam on the heat transfer through PCM and the electrical efficiency of PV-PCM systems has been numerically investigate. A comparative study on the impact of the porosity of metal foam ranging from 0.7 to 0.9 has been carried out. Furthermore, different inclination angles, 0° to 90°, have been considered to evaluate the impact of inclination angle on the natural convection enhancement through liquid PCM. Results indicated that increasing the inclination angle results in better natural convection of molten PCM and better heat transfer through PCM. Moreover, results represented that compared with the PV-PCM system, 6.8% and 9.8% enhancement in the average temperature and electrical efficiency, in the case of insertion of metal foam with porosity of 0.9, is achieved.

Solar Photovoltaics Integrated With Hydrated Salt-Based Phase Change Material

Abstract Maintaining the temperature of the photovoltaic (PV) panel within the described standard helps in achieving higher power conversion efficiency. To regulate the PV temperature, phase change material (PCM)-based cooling techniques have been proposed in several literature. However, most of the studies utilize organic PCMs whose low thermal conductivity confines their potential. Thus, in the proposed work, the rear side of the 20 Wp PV panel is coated with hydrated salt-based PCM and is integrated with an aluminum sheet (PV–PCM–Al) to increase the thermal conductivity of the system. The effect of the PV–PCM–Al panel in enhancing the PV efficiency is realized by comparing it with a standard uncooled PV panel. This concept was experimented under direct sunlight for about a week in Chennai, the southern part of India. To perceive the performance enhancement, thermal images were taken for both the cooled and uncooled PV panels. In addition, open-circuit voltage, short-circuit current, and power output were measured. The experimentation is also backed up by numerical simulations to understand the heat transfer characteristic features of the designed integrated PCM and aluminum cooling system. The experimentation results highlight that a maximum increase of about 7.67% in the PV efficiency was obtained using a cooled PV panel when compared to an uncooled PV panel. A maximum increase of 7.34% in the open-circuit voltage and a maximum drop of 4.6 °C in the PV temperature were obtained.

Performance enhancement of photovoltaic cells using phase change material (PCM) in winter

The performance of photovoltaic (PV) modules worsens due to increasing their operating temperature. In the current study, a passive cooling technique comprising an aluminum metal foam (AMF) with PCM for thermal regulation of a PV system is performed. Outdoors experiments are conducted comprising two modules: PV without any modifications and PV with AMF embedded in PCM denoted as PV/PCM/AMF. The temperature distribution on the surface of the PV panels, PCM temperature, open-circuit voltage, and output power produced were recorded during the winter period. The results revealed that the PV surface temperature of the PV-PCM/AFM system was 4 %, 7.4 %, and 13.2 % lower than that of conventional PV, and the power produced from PV-PCM/AFM system was 1.85 %, 3.38 %, and 4.14 % higher than that of conventional PV in December, January, and February, respectively.

PCM thermal conductivity effect on mechanism of PV/PCM thermal control characteristics

ABSTRACT According to the structure of photovoltaic/phase change material (PV/PCM), the mechanism of internal heat transfer, transmission, storage, and temperature control is analyzed, and a two-dimensional finite element analysis model of PV/PCM structure is established. This study is carried out on the effect of PCM thermal conductivity on internal temperature distribution characteristics of PV/PCM and temperature control characteristics of solar cells. The results show that the increase in thermal conductivity of PCM can prolong the temperature control time of solar cell in PV/PCM system, for example, when the thermal conductivity is increased from 0.2 W/(m·K) to1.5 W/(m·K) under a thickness of 4 cm, the duration when PV/PCM solar cell temperature is controlled below 40°C and extended from 52 min to 184 min. In addition, PV/PCM experimental prototypes are designed with the LA-SA-EG composite PCM peak melting point of 46°C and thermal conductivity of 0.8 W/(m·K) and 1.1 W/(m·K), respectively. The results indicate that compared with PCM-free solar cells, the maximum temperature of PV/PCM prototype solar cells with thermal conductivity of 0.8 W/(m·K) and 1.1 W/(m·K) is reduced by 10.8°C and 4.6°C, respectively, with average output power increased by 4.1% and 2.2%, respectively, under simulated light sources. Under natural light conditions, the average output power is increased by 6.9% and 4.3%, respectively. The results provide theoretical and experimental basis for the optimization of PV/PCM design by changing the thermal conductivity of PCM.

Investigation of Inorganic Phase Change Material for a Semi-Transparent Photovoltaic (STPV) Module

The semi-transparent photovoltaic (STPV) module is an emerging technology to harness the solar energy in the building. Nowadays, buildings are turning from energy consumers to energy producers due to the integration of the STPV module on the building envelopes and facades. In this research, the STPV module was integrated on the rooftop window of the experimental room at Kovilpatti (9°10′0″ N, 77°52′0″ E), Tamil Nadu, India. The performance of the STPV modules varies with respect to the geographical location, incident solar radiation, and surface temperature of the module. The surface temperature of the STPV module was regulated by the introduction of the mixture of graphene oxide and sodium sulphate decahydrate (Na2SO4·10H2O). The various concentration of the graphene oxide was mixed together with the Na2SO4·10H2O to enhance the thermal conductivity. The thermal conductivity of the mixture 0.3 concentration was found to be optimum from the analysis. The instantaneous peak temperature of the semi-transparent photovoltaic phase change material (STPV-PCM) module was reduced to 9 °C during summer compared to the reference STPV. At the same time, the energy conversion efficiency was increased by up to 9.4% compared to the conventional STPV module. Due to the incorporation of the graphene oxide and Na2SO4·10H2O, the daily output power production of the STPV module was improved by 12.16%.

Thermal regulation and performance assessment of a hybrid photovoltaic/thermal system using different combinations of nano-enhanced phase change materials

Combining hybrid photovoltaic/thermal (PV/T) and photovoltaic/phase change material (PV/PCM) systems in a so called hybrid PV/T/PCM system is a potential solution for the high temperature gradients and unsatisfactory thermal regulation in conventional PV/T systems. Several combinations of different PCMs and different types of nanomaterials at different loadings are employed in this study to overcome the increased PV-temperature levels in the presence of a PCM and improve both the cooling and the thermal regulation of hybrid systems. A finite difference numerical model was developed and validated to evaluate the average PV panel temperature, the temperature gain across the cooling fluid, the thermal and electrical efficiencies, and the temperature distribution along the PV panel for the hybrid PV/T/nano-enhanced PCM system. The effects of the solar concentration and the operation season (summer or winter) were also assessed. Four types of PCMs and four nanoparticle materials were used at high loadings of 10 wt %, 20 wt %, and 30 wt %. When paraffin wax RT35 is used as the PCM, although the temperature increasing magnitude along the panel decreases from 41% to 12%, PV-temperature levels increase compared to the conventional PV/T system (65 °C with RT35 compared to 47.5 °C without a PCM). Increasing the loading of nanoparticles in a PCM provides better cooling and improved overall performance. Among the nanomaterials, Multi-walled carbon nanotube is the best to obtain better cooling (52 °C for RT35/MWCNT at a loading of nanoparticles of 10 wt %) and higher overall performance. Also, the addition of nanoparticles is more effective at higher solar concentrations. The CaCl2.6H2O PCM provides better performance and relatively lower temperature levels, while the RT35 provides better thermal regulation of the PV panel, but at relatively higher temperature levels. No previous work has been conducted to study the effect of different combinations from the nano-enhanced PCMs on the performance and thermal regulation of the new hybrid PV/T/nanoPCM systems. In addition, the study is the first to assess their effect at high loadings of the nanomaterials and under different solar concentrations in summer and winter.

Experimental Investigations Conducted for the Characteristic Study of OM29 Phase Change Material and Its Incorporation in Photovoltaic Panel

The solar photovoltaic (PV) system is emerging energetically in meeting the present energy demands. A rise in PV module temperature reduces the electrical efficiency, which fails to meet the expected energy demand. The main objective of this research was to study the nature of OM29, which is an organic phase change material (PCM) used for PV module cooling during the summer season. A heat transfer network was developed to minimize the experimental difficulties and represent the working model as an electrical resistance circuit. Most existing PV module temperature (TPV) reduction technology fails to achieve the effective heat transfer from the PV module to PCM because there is an intermediate layer between the PV module and PCM. In this proposed method, liquid PCM is filled directly on the back surface of the PV module to overcome the conduction barrier and PCM attains the thermal energy directly from the PV module. Further, the rear side of the PCM is enclosed by tin combined with aluminium to avoid any leakages during phase change. Experimental results show that the PV module temperature decreased by a maximum of 1.2 °C using OM29 until 08:30. However, after 09:00, the OM29 PCM was unable to lower the TPV because OM29 is not capable of maintaining the latent heat property for a longer time and total amount of the PCM experimented in this study was not sufficient to store the PV module generated thermal energy for an entire day. The inability of the presented PCM to lower the temperature of the PV panel was attributed to the lower melting point of OM29. PCM back sheet was incapable of dissipating the stored PCM’s thermal energy to the ambient, and this makes the experimented PCM unsuitable for the selected location during summer.

Investigation of a binary eutectic mixture of phase change material for building integrated photovoltaic (BIPV) system

The incorporation of phase change material (PCM) into the building integrated semi-transparent photovoltaic (BISTPV) system is a promising technology to regulate the enhanced surface temperature of the photovoltaic (PV) system. In this work, Sodium Sulfate Decahydrate (Na2SO4·10H2O) and Zinc Nitrate Hexahydrate (N2O6Zn·6H2O) were mixed to form the binary eutectic PCM by heating mixing method. The results of Differential Scanning Calorimeter (DSC) characterization of those eutectic mixtures showed that the molar mass proportion of 70% weight of Na2SO4·10H2O and 30% weight N2O6Zn·6H2O was an optimum eutectic mixture for the solar energy applications. The developed eutectic mixture was employed in the specially designed and fabricated building-integrated semi-transparent photovoltaic phase change material (BISTPV-PCM) system to regulate BISTPV cell temperature. The experimentation was carried out at the outdoor environmental conditions in the region of Kovilpatti (9°10′0″N, 77°52′0″E), Tamilnadu, India throughout the year of 2018. The instantaneous peak temperature was reduced up to 12 ᵒC for the BISTPV-PCM system compared to the non-PCM counterpart. The annual output power generated from the BISTPV module was 34,287 W h/year which increased to 37,024 W h/year by using PCM.

Power improvement of finned solar photovoltaic phase change material system

Fins enabled Phase Change Material (FPCM) has potential to take away the thermal energy from photovoltaic (PV) and increase the efficiency. This study analyses the PV-FPCM arrangement and presents a mathematical model. The arrangement is studied under various azimuths of wind, its flow rates, temperature of surroundings, phase change temperature and dimensions of FPCM confinement. The duration of power improvement of PV using FPCM, power production, efficiency improvement and Power-Voltage (P–V) curves are reported. The outcomes convey that as azimuth of wind changes from 75° to 0°, the duration of power improvement elevates from 6.1 h to 7.3 h for 5 cm deep FPCM confinement. It increases from 4.9 h to 5.8 h for 4 cm deep FPCM confinement. Moreover, decrement in wind flow rate from 6 m/s to 1 m/s, contracts the duration of power improvement from 7.8 h to 6.1 h.

Optimization of finned solar photovoltaic phase change material (finned pv pcm) system

Heat generation during the operation of the photovoltaic (PV) cell raises its temperature and results in reduced electrical output. The heat produced in the process can be removed by attaching phase change material (PCM) at the back of the PV panel which can contain the PV temperature substantially and increase its efficiency. Fins can be used inside the PCM container to enhance the heat transfer. In literature, it is observed that as soon as PCM is melted completely, the heat extraction rate of PCM reduces which again leads to increase in PV temperature. However, the study carrying out the optimization of Finned-PV-PCM system to keep PV temperature low during operation for different solar irradiance levels is not available in literature. Thus, in the current study, the most suitable depth of PCM container is calculated for different solar irradiance levels. In addition, how it is affected with spacing between successive fins, fin length and fin thickness has been studied. The best fin dimensions are also calculated. The results show that the most suitable depth of PCM container is 2.8 cm for ∑IT = 3 kWh/m2/day and 4.6 cm for ∑IT = 5 kWh/m2/day for the chosen parameters. The best spacing between successive fins (to keep PV temperature low) is 25 cm, best fin thickness is 2 mm and best fin length is the one when it touches the bottom of the container. PV, PV-PCM and Finned-PV-PCM systems are also compared. For PV-PCM system (without fins), the most suitable depth of PCM container is 2.3 cm for ∑IT = 3 kWh/m2/day and 3.9 cm for ∑IT = 5 kWh/m2/day.