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Scientific Reports volume 15, Article number: 37908 (2025) Cite this article
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The efficiency of photovoltaic (PV) panels significantly decreases due to temperature rise under solar irradiation, a critical challenge especially in hot climates. This study addresses this issue by developing a highly efficient hybrid phase-change material (PCM) for PV thermal management. Copper oxide nanoparticles (CuO NPs) were synthesized via chemical precipitation and characterized using XRD and AFM, confirming high purity and a crystalline size of 18–25 nm. The nanoparticles were incorporated into paraffin wax at varying concentrations (0.5–3 wt%) to form the hybrid PCM. The optimal concentration of 2 wt% yielded a remarkable 381.8% enhancement in thermal conductivity compared to pure paraffin. When applied as a passive cooling system to the rear of PV panels, this nano-enhanced PCM achieved an average operating temperature reduction of 14.4 °C. This thermal regulation led to a 29.11% increase in maximum power output (from 28.82 to 37.21 W) and improved energy conversion efficiency from 9.44 to 12.18% under peak irradiance conditions. Furthermore, the system boosted daily energy yield by 22.75%. The novelty of this work lies in the optimization of CuO NP concentration for maximum thermal enhancement and the demonstration of its superior performance under real-world, high-temperature conditions. These results confirm the potential of this nano-enhanced PCM as a practical and effective solution for improving the efficiency and longevity of solar energy systems.
Amid the global transition toward sustainable energy systems, photovoltaic (PV) panels face critical efficiency challenges due to thermal rise, which causes significant energy loss. PV cells absorb 80–85% of solar radiation, converting it into waste heat rather than electrical energy¹. This effect manifests clearly in a 0.5% reduction in open-circuit voltage (V < sub > oc < /sub >) per degree Celsius above the nominal temperature (25 °C), a problem exacerbated in hot climates where panel temperatures can reach 70 °C during summer.
To address this issue, three primary heat management strategies have emerged:
Phase Change Materials (PCMs), which utilize latent heat of phase transition to absorb excess thermal energy^2,3,4,5.
Hybrid cooling systems integrating water-based or air-based cooling with PCMs.
Thermochemical Heat Storage (TCHS) systems employing materials such as hydrated salts⁶.
These technologies have demonstrated the ability to enhance solar system efficiency by 15–20%^7,8,9,10, despite ongoing challenges in developing low-cost materials and smart infrastructure^11,12,13.
Thermal energy storage serves as a fundamental solution for maximizing renewable energy utilization, classified into three types:
Sensible Heat Storage (SHS), involving temperature change without phase transition.
Latent Heat Storage (LHS), leveraging energy from phase transitions.
Thermochemical Heat Storage (TCHS), relying on reversible chemical reactions.
LHS systems exhibit superior storage capacity^14,15, making them the optimal choice for thermal management applications. Phase Change Materials (PCMs) represent the most prominent LHS technology due to their exceptional energy storage capacity during phase transitions¹⁶.
PCMs are classified based on transition temperature:
Low-temperature (< 15 °C)
Medium-temperature (15–90 °C)
High-temperature (> 90 °C)
They are also categorized by chemical composition:
Organic PCMs (paraffins, fatty acids): Advantages: Thermal/chemical stability, resistance to supercooling. Disadvantages: Low thermal conductivity (0.1–0.3 W/m K).
Inorganic PCMs (hydrated salts, alloys): Advantages: Higher thermal conductivity (0.4–0.7 W/m K), doubled storage capacity. Disadvantages: Moderate chemical stability.
Eutectic PCMs (multi-component mixtures):
Advantages: Low melting points, stability during phase transition.
Optimal PCM selection requires a comprehensive evaluation of thermal, physical, and chemical properties, alongside economic feasibility. Key criteria include storage capacity, thermal conductivity, chemical stability, heat transfer rates, and overall cost. This holistic framework ensures the selection of the most suitable materials for each application, considering specific environmental and design conditions.
PV panel cooling systems using PCMs (PV-PCM) have evolved significantly since the pioneering study integrating a solar panel with an RT25 PCM system and thermal fins. Results showed a surface temperature reduction from 45 to below 35 °C using a 30-mm PCM layer¹⁷. These findings stimulated subsequent research exploring diverse PCM types under varying climatic conditions, enhancing the scientific understanding of efficiency mechanisms. Recent research focuses on enhancing PCM performance via nanomaterial integration. An RT55 system reinforced with 2% Al₂O₃ nanoparticles achieved a 7.1% improvement in daily efficiency¹⁸, while copper (Cu) and silicon carbide (SiC) nanoparticles reduced temperature by 4–5 °C with a 4.3% performance enhancement¹⁹. Studies also indicate that adding 0.5% TiO₂ nanoparticles to paraffin wax can improve panel efficiency by 2.1% alongside a 13 °C thermal reduction²⁰.
Advanced hybrid systems combining multiple technologies have emerged. A PVT-PCM system achieved a thermal efficiency of 48.5%²¹, while integrating ZnO nanofluids (0.2 wt%) with paraffin wax PCM improved energy efficiency by over 23% compared to conventional panels²². Using a silica/water mixture (3 wt%) with paraffin increased thermal efficiency by 10%²³. Research also reveals the impact of operational factors: increasing tilt angle (0°–90°) extends PCM melting time while reducing temperature by 0.4–12%²⁴, whereas top-to-bottom water flow achieves optimal results—reducing temperature by 5.4 °C and improving efficiency to 12.4%²⁵. Optimal sequencing of PCMs by melting point can increase melting duration by 18% and thermal efficiency by 33%²⁶.
Despite these advancements, PV-PCM systems still face challenges, primarily the inherently low thermal conductivity of most PCMs like paraffin, which limits heat dissipation rates. While nanoparticle integration is a promising solution Table 1, identifying the optimal type and concentration for maximum performance and cost-effectiveness remains a key research gap. Furthermore, comprehensive studies under real-world, high-irradiance climatic conditions are necessary for practical validation.
Furthermore, recent explorations into bio-based phase change materials²⁷ and advanced nanocomposites utilizing materials like graphene²⁸ have shown promising pathways for enhancing sustainability and thermal performance. Comprehensive reviews of these nano-enhanced systems highlight their potential to significantly improve solar thermal energy applications²⁹.
Therefore, the novelty and primary objectives of this work are: (1) To synthesize and characterize copper oxide nanoparticles (CuO NPs) specifically for thermal enhancement; (2) To experimentally determine the optimal weight fraction of CuO NPs (2 wt%) in paraffin wax that maximizes thermal conductivity while maintaining stability; (3) To design, fabricate, and evaluate a PV cooling system based on this optimized hybrid PCM under the harsh summer conditions of Aleppo, Syria, providing a clear comparison against both an uncooled panel and one cooled with pure paraffin.
Copper oxide nanoparticles (CuO NPs) were synthesized via a chemical precipitation method. A total of 4.5 g of copper sulfate pentahydrate (CuSO₄·5H₂O) was dissolved in 100 mL of absolute ethanol under magnetic stirring at 500 rpm for 10 min at 25 ± 2 °C. Subsequently, a separate solution was prepared by dissolving 4.5 g of sodium hydroxide (NaOH) in 200 mL of ethanol. The NaOH solution was gradually added (at a rate of 1 mL/min) to the copper sulfate solution under continuous stirring at 800 rpm. The addition process lasted 60 min while maintaining the temperature at 25 ± 2 °C and adjusting the pH to 8.0 ± 0.2.
The mixture was then heated to 80 ± 2 °C for 2 h until a dark brown gel formed. The precipitate was filtered and washed multiple times with an ethanol–water mixture (3:1 ratio). The washed precipitate was dried in an oven at 80 ± 5 °C for 12 h, followed by calcination in an electric furnace at 400 ± 5 °C for 2 h (heating rate: 5 °C/min). Finally, the sample was ground for 15 min using an agate mortar and stored in an airtight glass container with silica gel to prevent moisture absorption.
The properties of the synthesized CuO NPs were determined using the following techniques:
X-Ray Diffraction (XRD): Analysis was performed using a PANalytical X’Pert PRO MPD diffractometer with Cu Kα radiation (λ = 1.54060 Å).
Scanning range (2θ): 20° to 80°
Operating conditions: 40 kV voltage, 25 mA current
Crystallite size (Dₐᵥ) was calculated using the Debye–Scherrer equation:
Where: β = Full width at half maximum (FWHM) of the peak, λ = X-ray wavelength.
Atomic Force Microscopy (AFM): Microscopic images were acquired using a Nano Surf microscope to analyze nanoscale particle distribution and surface morphology.
The influence of synthesized CuO NPs on the thermal conductivity of paraffin wax (supplied by Kmart Chemical Technology Company) was investigated. Composite samples were prepared by incorporating varying concentrations of CuO NPs (1, 1.5, 2, 2.5, and 3 wt% relative to the wax mass). Paraffin wax was melted in a water bath at 75 °C, after which nanoparticles were added under continuous mechanical stirring until homogeneous dispersion was achieved. To ensure a uniform and stable dispersion and to mitigate nanoparticle agglomeration, the mixture was subsequently subjected to ultrasonic homogenization using a [Insert ultrasonic homogenizer (750 W, 20 kHz) at 750 W for 30 min while maintaining the temperature at 75 ± 2 °C. The mixture was cast into molds (14 × 14 × 1 cm³) and allowed to solidify.
Thermal conductivity measurements were conducted using a custom apparatus consisting of:
A thermostatically controlled bath with heating resistors
Integrated temperature sensors
A thermally insulated test chamber for samples Both modified (CuO-enhanced) and unmodified paraffin samples were placed in the test chamber. The temperatures of the upper and lower surfaces were monitored by direct-contact thermal sensors. Thermal conductivity (*k*) was calculated according to Fourier’s Law (Eq. 2), as illustrated in Fig. 1:
Thermal conductivity measurement.
Where: Q: Heat transfer rate (W), k: Thermal conductivity coefficient (W/m·K), A: Cross-sectional area of the sample (m²), ΔT: Temperature difference between sample surfaces (K or  °C), d: Sample thickness (m).
The heat transfer rate Q was calculated using Eq. (3):
where: I: Current intensity (A), V: Voltage (V).
The thermal conductivity enhancement percentage (k) of the nano-CuO/paraffin phase change material (PCM) composite was calculated using the following equation:
The solar panel efficiency (η) represents the ratio of the maximum electrical power output (P_max)to the incident solar energy on the panel surface, expressed by the equation:
where: V_m and I_m :Voltage and current at the maximum power point (MPP), E: Solar irradiance (W/m²), A: Effective panel area (m²).
Efficiency is significantly influenced by panel temperature, as V < sub > m < /sub > decreases with rising temperature according to the temperature coefficient.
The fill factor serves as an indicator of solar cell quality, calculated as the ratio of the theoretical maximum power (P_o = V_oc⋅I_sc) to the actual maximum power output (Pmax):
where: V_oc: Open-circuit voltage, I_sc: Short-circuit current.
The fill factor (FF) is inversely proportional to temperature due to reduced V_oc, making it a sensitive criterion for performance assessment under varying operational conditions.
The normalized power output efficiency is defined as the ratio of measured output power under actual conditions to that measured under standard test conditions (STC). This efficiency is calculated as a percentage using the following equation:
where: ({text{P}}_{{{text{actual}}}}): Electrical power output (W) measured under real operating conditions (site-specific irradiance, temperature, and environmental factors), ({text{P}}_{{{text{stc}}}}): Electrical power output (W) measured under Standard Test Conditions (STC: 1000 W/m², 25 °C cell temperature, AM 1.5 spectrum).
All experiments were conducted outdoors in Aleppo, Syria (Latitude: 36.2021° N, Longitude: 37.1343° E) during July 2024. Monocrystalline silicon solar panels (General Gold Co.) with dimensions 67 × 44.5 × 1.7 cm and rated power 50 W were employed. The panels featured an open-circuit voltage (V_oc) of 22 V and short-circuit current (I_sc) of 3 A. An aluminum containment unit (64 × 42 × 2.5 cm) housing the nano-enhanced paraffin wax was thermally coupled to the rear surface of each panel.
The PV modules were mounted at a 33° tilt angle facing south to maximize solar irradiance exposure. Temperature monitoring was performed using Weewooday K-type thermocouples strategically positioned across the panel surface to calculate the average PV module temperature for each measurement interval. Voltage and current measurements were recorded with a DT830B digital multimeter (operational ranges: 200 mV–2000 V DC, 200 μA–10 A).
The experiments were repeated over three consecutive days to ensure result consistency and repeatability; the data presented is from a representative day (July 18, 2024) with stable weather conditions. The accuracies and uncertainties of the measuring instruments were as follows: K-type thermocouples (± 0.5 °C), digital multimeter DT830B (± 0.5% of reading + 2 digits), and the pyranometer (± 5 W/m²). The uncertainty in thermal conductivity measurements was calculated to be ± 3.5%, and the uncertainty in electrical power output was ± 2.1%.
Electrical power output was calculated using Eq. (8). Experiments were conducted over three consecutive days with 9-h daily monitoring periods (08:00–17:00 local time).
where: ({text{Pmax}}): Maximum generated power (W), ({text{Imax}}): Maximum current (A), ({text{Vmax}}): Maximum voltage (V).
The average power variation for each test case was determined using Eq. (9):
where: ({text{P}}_{max 2}): Maximum power output of modified solar panel, ({text{P}}_{max 1}): Maximum power output of reference solar panel, 3. Results and Discussion.
The X-ray diffraction (XRD) pattern of synthesized copper oxide nanoparticles (CuO NPs) in Fig. 2 exhibits characteristic peaks at diffraction angles (2θ) between 20° and 80°. These peak positions precisely match the (hkl) crystallographic planes of copper oxide (JCPDS card no. 05-0661). The most prominent peak at 35.5° corresponds to the (1̄11) plane, while other distinctive peaks appear at 38.7° (111), 48.7° (202), 58.3° (113), and 61.5° (311), collectively confirming the monoclinic tenorite structure of CuO.
X-ray diffraction (XRD) pattern of synthesized copper oxide nanoparticles (CuO NPs) prepared via chemical precipitation.
Crystallite size was estimated at 18–25 nm through Scherrer equation analysis of the dominant (1̄11) peak using Cu Kα radiation (λ = 1.5406 Å) and the full width at half maximum (FWHM). Peak broadening indicates the nanoscale nature of the material, while symmetrical peak profiles confirm homogeneous particle size distribution.
The absence of extraneous peaks demonstrates high sample purity with no detectable secondary phases (e.g., Cu₂O or metallic Cu). Minimal baseline scattering further confirms the absence of amorphous components. The measured diffraction angles show precise alignment with reference data for phase-pure CuO, confirming successful synthesis.
Figure 3 presents two-dimensional (2D) and three-dimensional (3D) atomic force microscopy (AFM) images of copper oxide nanoparticles (CuO NPs), revealing distinctive surface characteristics that confirm the nanoscale nature of the material. The 3D image shows homogeneous nanoscale aggregates uniformly distributed across the surface, with topographic heights ranging from − 45 nm to + 50 nm. This indicates relative surface smoothness with localized nanoprotrusions.
Atomic force microscopy (AFM) 2D and 3D images of copper oxide nanoparticles (CuO NPs).
The 2D image demonstrates uniform nanoparticle distribution across a 5 × 5 μm scan area, exhibiting fine surface topography indicative of nanoscale roughness. The limited and homogeneous surface roughness confirms particle sizes within the nanoscale regime (< 100 nm).
Surface roughness analysis yielded low values (within several nanometers), consistent with monodisperse nanoparticles. The absence of large topographic features or deep voids confirms minimal particle aggregation and no surface contaminants.
These AFM-derived characteristics—including particle distribution, height variation, and roughness parameters—provide compelling evidence of successful CuO NP synthesis with excellent size homogeneity and surface distribution. These findings align with XRD crystallite size analysis (18–25 nm), confirming synthesis consistency across characterization techniques.
A concentration gradient of CuO NPs (0.5, 1, 1.5, 2, 2.5, and 3 wt%) was tested to identify the optimal loading for thermal conductivity enhancement. The selection of 2 wt% as the optimal concentration was based on it yielding the highest thermal conductivity value (2.15 W/m K). Concentrations beyond this point led to a decline in performance due to increased viscosity and nanoparticle agglomeration, which hinders homogeneous dispersion and reduces the effective surface area for heat transfer, as confirmed by visual inspection showing non-uniform brown patches in the composite.
As presented in Table 2, incorporating copper oxide nanoparticles (CuO NPs) significantly enhanced the thermal properties of paraffin wax. The baseline thermal conductivity of unmodified paraffin wax measured 0.4857 W/m K. With the addition of 0.5 wt% nanoparticles, thermal conductivity increased substantially to 1.12 W/m K, representing a 130.6% enhancement relative to the reference sample.
A positive correlation between nanoparticle concentration and thermal conductivity was observed up to 2 wt%, where peak thermal conductivity reached 2.15 W/m K (381.8% improvement). However, increasing the concentration to 2.5 wt% reduced thermal conductivity to 1.57 W/m K. This reduction is attributed to nanoparticle agglomeration and heterogeneous dispersion within the wax matrix, as evidenced by microscopic observations revealing non-uniform brown patches on sample surfaces.
These results indicate an optimal nanoparticle loading of 2 wt%, which maximizes thermal conductivity enhancement while maintaining homogeneous particle distribution. The thermal improvement mechanisms include:
Inherent high thermal conductivity of CuO nanoparticles
Formation of efficient thermal networks at optimal concentrations
Enhanced interfacial interactions between nanoparticles and wax molecules
Figure 4 data demonstrate a significant thermal conductivity enhancement of 381.8% at the optimal concentration (2 wt%), with a pronounced reduction observed at higher concentrations due to nanoparticle agglomeration phenomena.
Effect of copper oxide nanoparticles on thermal conductivity of paraffin wax.
These findings provide critical insights for designing thermally enhanced phase change materials (PCMs), highlighting the necessity for precise control of nanofiller loading concentrations to achieve an optimal balance between thermal conductivity improvement and homogeneous dispersion stability.
Differential Scanning Calorimetry (DSC) analysis confirmed that the addition of up to 2 wt% CuO NPs did not significantly alter the melting and solidification points of the paraffin wax, ensuring the latent heat storage functionality remained the primary cooling mechanism. However, at higher concentrations (e.g., 2.5 wt%), sedimentation of agglomerated nanoparticles was observed over time, which could potentially lead to clogging and reduced long-term efficiency in a real-world application. This underscores the importance of optimal loading not just for initial performance but also for suspension stability.
The uncooled reference panel exhibited significant performance degradation under elevated temperatures during harsh July conditions. At solar noon (12:00) with 1025 W/m² irradiance, the panel surface temperature peaked at 77.1 °C. This thermal stress reduced output voltage to 15.25 V (compared to the nominal 22V), demonstrating the direct adverse impact of temperature rise on photovoltaic properties.
The degradation manifested as a 42% efficiency loss, with maximum power output limited to 28.82 W. Temperature elevation adversely affected the cell fill factor (FF), diminishing energy conversion efficiency through increased internal resistance Table 3.
Experimental results from the PCM-integrated system (18 July 2024) in Table 4 demonstrated significant thermal and electrical performance improvements compared to the reference panel. The phase-change cooling system effectively reduced surface temperatures during peak solar irradiance, with the cooled panel reaching a maximum temperature of 66.12 °C at noon versus 77.1 °C for the reference panel—representing a 14.2% reduction under identical 1025 W/m² irradiance. This thermal mitigation is attributed to paraffin’s latent heat absorption during phase transition, which diminished heat transfer to PV cells.
This thermal enhancement positively influenced electrical properties, increasing output power by 23.8% (35.69 W vs. 28.82 W for the reference panel during identical periods). The improvement resulted from optimized voltage and current coefficients at lower temperatures, evidenced by higher operational voltage (15.79 V vs. 15.25 V at noon). This voltage elevation confirms the detrimental impact of temperature elevation on monocrystalline semiconductor properties.
These findings underscore the critical need for active cooling systems in high-irradiance regions, highlighting thermal management’s essential role in achieving:
Output voltage stabilization,
Thermal loss minimization,
Overall efficiency optimization.
Table 5 presents performance data for the system integrated with nano-enhanced paraffin (PCM/CuO NPs, k = 2.15 W/m K) recorded on 18 July 2024, demonstrating superior thermal regulation and electrical output compared to conventional systems. The nano-enhanced panel achieved a peak surface temperature of 55.3 °C at solar noon under 1025 W/m² irradiance, versus 66.12 °C for the pure paraffin-cooled panel—representing an additional 16.36% temperature reduction. This improvement is attributed to the enhanced thermal conductivity of copper oxide nanoparticles, which optimized latent heat transfer within the phase change material.
This advanced cooling significantly improved electrical parameters: peak power output reached 37.21 W compared to 35.69 W for the unenhanced paraffin system (4.3% enhancement). Concurrently, maximum voltage increased to 16.25 V versus 15.79 V (2.9% increase), demonstrating improved semiconductor performance at lower operating temperatures.
The achieved temperature reduction of 21.8 °C and power increase of 29.11% compare favorably with recent literature (as summarized in Table 1), where improvements typically range from 4 to 13 °C and 2–23% depending on the nanoparticle and climate. For instance, our system outperforms the 13 °C reduction reported with 0.5% TiO₂²⁰ and the 4.3% power boost with Cu/SiC¹⁹, highlighting the effectiveness of the optimized 2% CuO concentration. The results are attributed to the formation of efficient thermal percolation networks within the PCM, significantly enhancing heat dissipation from the PV panel.
Table 6 compares the performance of standard photovoltaic modules versus those integrated with the hybrid cooling system (paraffin wax reinforced with copper oxide nanoparticles).
For enhanced visual comparison of the thermal and electrical performance across all three systems, the data from Tables 3, 4, and 5 are graphically summarized in Fig. 5. The line charts clearly illustrate the superior performance of the hybrid nPCM cooling system throughout the day.
Comparative performance evaluation of the photovoltaic panels under different cooling conditions: (a) surface temperature profile, (b) electrical power output. Note: Values in parentheses represent the change relative to the reference panel.
Figure 5a depicts the panel surface temperature variation. The reference panel (uncooled) exhibits the highest temperatures, peaking at 77.1 °C at noon. The paraffin wax PCM system effectively reduces this peak temperature to 66.12 °C. Notably, the hybrid nPCM panel demonstrates the most effective cooling, maintaining the lowest temperatures at all times and achieving a significantly reduced peak of only 55.3 °C. This represents a substantial improvement and a clear visual demonstration of the synergistic effect of nanoparticle enhancement.
Correspondingly, Fig. 5b shows the power output generated by each panel. The performance hierarchy is visually confirmed: the hybrid nPCM system consistently yields the highest power output, followed by the pure paraffin system, with the reference uncooled panel producing the least power. The maximum power achievement of 37.21 W by the hybrid system at noon is graphically evident, starkly contrasting with the 28.82 W from the reference panel. These curves effectively underscore the direct positive correlation between reduced operating temperature and enhanced electrical output, validating the core objective of this cooling strategy.
Physical analysis revealed that the cooling mechanism relies on nanoparticle-induced enhancement of the phase change material’s thermal conductivity from 0.4857 to 2.15 W/m K. The homogeneous distribution of nanoparticles at 2 wt% concentration establishes efficient thermal percolation networks. The high surface-to-volume ratio of nanoparticles significantly improved interfacial heat transfer.
From an electro-thermal perspective, temperature reduction enhanced P–N junction characteristics by:
Decreasing minority carrier concentrations
Suppressing reverse leakage current
Improving cell fill factor by 5.9%
Performance analysis demonstrated peak efficiency enhancement from 9.44% to 12.18% (29% relative gain), with 22.75% improvement in daily energy yield. These results confirm the system’s efficacy in photovoltaic performance optimization through precise thermal management, achieving:
Output voltage stabilization
Thermal loss minimization
Operational reliability enhancement
This study demonstrates the significant potential of the optimized hybrid PCM; however, some limitations should be acknowledged. The long-term cycling stability (over hundreds of melt-freeze cycles) and the chemical stability of the nanocomposite were not assessed. Furthermore, a detailed techno-economic analysis is required to evaluate the cost–benefit ratio and payback period compared to conventional cooling systems. Future work will focus on accelerating aging tests, exploring the synergy of hybrid nanoparticles (e.g., CuO with graphene), and developing advanced encapsulation techniques for large-scale industrial deployment.
This study has achieved tangible scientific progress in enhancing the efficiency of photovoltaic systems through the development of an innovative cooling system based on phase change materials (PCMs) enhanced with nanoparticles. The results demonstrated the successful synthesis of copper oxide nanoparticles (CuO NPs) with a pure crystalline structure and homogeneous size distribution between 18 and 25 nm, as confirmed by XRD and AFM analyses. Upon integrating these nanoparticles at 2% by weight with paraffin wax, a hybrid material was developed that exhibited qualitative improvement in thermal properties, manifested in a 381.8% increase in thermal conductivity compared to the base material.
The developed cooling system proved highly efficient in thermal control, recording an average reduction in operating temperature of 14.4 °C, while achieving a maximum thermal reduction of 21.80 °C under peak irradiance conditions. This thermal improvement translated into substantial enhancements in photovoltaic performance, represented by a 29.11% increase in maximum power output, a rise in peak efficiency from 9.44 to 12.18%, and a boost in daily energy yield of 22.75%. The fundamental mechanisms underlying these improvements lie in the formation of effective thermal conductive networks, enhancement of latent heat transfer dynamics, and reduction of thermal loss at the P–N junction.
These findings open new horizons for developing sustainable solutions in thermal management for renewable energy applications, with the potential for expansion into studying multi-component hybrid nanocomposites, developing precise mathematical models, and assessing the economic feasibility for large-scale industrial implementation.
All data and materials related to this study are included within the manuscript.
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The authors gratefully acknowledge the support provided by the University of Aleppo
This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.
Department of Basic Sciences, Faculty of Electrical and Electronic Engineering, University of Aleppo, Aleppo, Syria
Abdulrazzaq Hammal
Department of Environmental Engineering Technologies, Faculty of Technical Engineering, University of Aleppo, Aleppo, Syria
Bahia Sheikh Al-Qassabeen & Khaldoun Hafez
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Abdulrazzaq Hammal: Conducted the chemical experiments and core testing, and wrote the main manuscript text. Khaldoun Hafez and Bahia Sheikh Al-Qassabeen: Performed the electrical experiments and calculations, and analyzed the results.
Correspondence to Abdulrazzaq Hammal.
The authors declare no competing interests.
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Hammal, A., Al-Qassabeen, B.S. & Hafez, K. Improving solar panel performance using a paraffin wax/copper oxide nanoparticle hybrid phase change material. Sci Rep 15, 37908 (2025). https://doi.org/10.1038/s41598-025-22742-4
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Received: 12 July 2025
Accepted: 30 September 2025
Published: 29 October 2025
Version of record: 29 October 2025
DOI: https://doi.org/10.1038/s41598-025-22742-4
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