![Schematic of PV/T system with nanofluid as (a) coolant [49], (b) spectral filter [50], (c) coolant and spectral filter with double-pass channel [51], and (d) coolant and spectral filter with separate channels [52]](https://www.researchgate.net/profile/Ehsan-Ebrahimnia-Bajestan/publication/315341398/figure/fig1/AS:473242059186176@1489841107098/Schematic-of-PV-T-system-with-nanofluid-as-a-coolant-49-b-spectral-filter-50_Q320.jpg)
![(a) Variation of PV temperature with Reynolds number (concentration ratio=40) studied by Rawadan et al. [53] and (b) Variation of PV temperature and increment of PV output power with mass flow rate reported by Karami and Rahimi [55] for different nanoparticle concentrations.](https://www.researchgate.net/profile/Ehsan-Ebrahimnia-Bajestan/publication/315341398/figure/fig7/AS:667883860406278@1536247329489/a-Variation-of-PV-temperature-with-Reynolds-number-concentration-ratio40-studied-by_Q320.jpg)
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Performance of nanofluid-based photovoltaic/thermal systems: A review
Abstract and Figures
Recently, applying nanofluids in PV/T systems for improving the performance of these systems has been fascinating many researchers. In this kind of research, nanofluids are employed in the PV/T systems as coolant or optical filter. To emphasis the capability of the nanofluids in PV/T systems, the present study aims first, to comprehensively review the features, structures, and the outcomes of PV/T system that applied nanofluids and investigated the effectiveness of nanofluids, and second, to comprehensively analyze the effective parameters on the performance of a nanofluid-based flat plate photovoltaic/thermal system in both laminar and turbulent regime. In this study, with respect to literature, a vast attempt has been done to study the effects of nanofluids parameters including volume fraction (0–4%), size (21 nm and 100 nm) and type of nanoparticles (TiO2 and Al2O3), as well as type of base fluid (water and mixture of ethylene glycol-water). The accuracy of proposed mathematical model was demonstrated through the comparison of predicted results and the available data in the literature. It can be concluded from the results that, to improve the performance of the system, adding nanoparticles is more efficient in laminar regime compared to turbulent one. The results also indicated that using nanoparticles of larger diameter leads to greater total energy and exergy efficiency in the turbulent regime, while contrary behavior is observed in laminar flow. Moreover, it was observed that employing aluminum oxide in nanofluids improves the system performance more than titanium oxide, where water based nanofluids show higher energy and exergy efficiency compared to ethylene glycol-water based nanofluids.
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Supplementary resources (2)
... Nanofluid studies on particle size and volume concentration effects, surfactant application for improved nanofluid stability, fluid temperature effects, intake velocity, and convective heat transfer performance were described by Ganvir et al. (2017). Basic fluids may include aqua, refrigerants, 1-, 2-ethanediol, or lipids (Yazdanifard et al. 2017). ...
This research investigates the effects of multi-slip conditions and entropy production on the flow of viscoelastic (Jeffrey) nanofluids in asymmetric channels, to determine the implications for healthcare applications such as cryopreservation and therapeutic thermal devices. By employing numerical simulations via the Shooting method and NDSolve tool, we examine the influence of motile microorganisms on the fluid’s thermal and entropic characteristics. Our findings, illustrated through graphical analysis, demonstrate that optimizing thermal slip and minimizing viscous slip can significantly reduce entropy generation. Additionally, we observe that the thermal profiles are affected by the Brinkman number-diminishing in size, yet expanding due to the Jeffrey fluid’s properties. This investigation not only advances our understanding of microbe motion in physiological fluids but also opens directions for developing precise therapeutic and diagnostic tools for microbial infections and related disorders.
... Recent investigations have focused on the use of numerous nanofluids as coolants in PV type system. Nanofluids are used in PV/T systems in dual primary methods: as a coolant and as a spectral filter (Yazdanifard, Ameri, and Ebrahimnia-Bajestan 2017). Thermal and spectral characteristics of nanofluids have been discovered to be superior to those of conventional heat transfer fluids (Hassani et al. 2016;Hammad 1995) described the efficiency of a smooth-plate type collector cool down by a heat pipe based system. ...
Photovoltaic (PV) panels play a crucial role in solar systems but are susceptible to efficiency losses caused by rising surface temperatures. This research explores four distinct recycle-type double-pass hybrid PV/T designs, employing steady-state models to cool the PV panels. The first and second designs mount the PV panel on the absorber plate, while the third and fourth designs position it directly over the absorber plate without a glass cover, allowing the sun's radiation to fall directly on the PV module. The study investigates the significant impacts of varying values of ṁ (0.03–0.15 kg/sec), G (0.3–1.8), D (1.0–6.0), I (300–1000 W/m2), and P (0.4–0.95) on thermal and electrical efficiency, as well as net electrical power generation, taking into account pressure loss during the flow. Through the analytical study, Design-IV demonstrates the highest net electrical power, estimated at 54.82W, which is 6.27% higher than Design-III, achieved at a recycling ratio, mass flow rate, depth ratio, and packing factor of 0.9, 0.15 kg/s, 3, and 0.5, respectively. Additionally, the input parameters are optimized using the Response Surface Methodology (RSM) technique. The analysis of variance (ANOVA) reveals a significant coefficient (R2) value approaching unity, indicating a strong fit of the response model to the analysed data. By considering both single and multi-objective optimization scenarios, the study identifies optimal parameters for each PV/T design through the interaction of operational parameters. This research contributes to enhancing the efficiency and performance of double-pass recycle-type hybrid PV/T systems, enabling sustainable and effective utilization of solar energy resources.
... Table .3 shows the values of the constant coefficients for each nanofluid under a certain flow condition for volume fractions from 1 % to 4 % [19,20]. Although the Nusselt number of copper oxide (CuO) is only for the volume fractions from 1 % to 2 %, it is assumed that the behavior of the Nusslet number for the rest of volume concentrations would follow the same behavior. ...
Conventional photovoltaic (PV) systems have elevated temperatures in the hot climate of Riyadh, resulting in reduced electrical power generation. Therefore, nanofluids are employed in photovoltaic-thermal (PV-T) systems to absorb the self-generated heat that limits efficient operation. In addition, developing deep learning models would help improve the optimization and control of the proposed system. This study's primary goal is to numerically examine a PV-T system under the influence of using various nanofluids with varying volume fractions in the hot climate of Riyadh and to develop time-series deep learning algorithms based on the findings in this examination to predict the PV-T system's potential. A mathematical model to investigate the PV-T panel performance under various volume concentrations and nanofluids is proposed. The generated data from the different nanofluids is deployed to train a deep learning model, which is convolutional neural networks integrated with two layers of long short-term memory (CNN-LSTM), in order to predict the PV-T panel temperature. According to the investigation's findings, the best PV-T coolant is CuO nanofluid at 4 % volume concentration. Utilizing the aforementioned nanofluid can deliver an enhancement in the average daytime PV-T panel temperature, electrical, thermal, and total exergy efficiency by 34.5 °C, 16.7 %, 79.2 %, and 18.07 %, respectively. The developed deep learning algorithms were evaluated using the mean absolute error (MAE) and coefficient of determination (R2) and scored 0.18–0.35 and 97.5–98.75 %, respectively.
... The heat transfer rate and thermal conductivity of nano-fluids are much better than those of conventional fluids. PV/T systems using nano-fluids showed higher energy and exergy efficiency than conventional fluids [10,11]. The effects of various factors such as nanoparticle concentration, type, mass flow rate, and inlet temperature, were extensively studied to maximize the system performance. ...
Water and refrigerant-based photovoltaic/thermal (PV/T) systems have substantial promise as sustainable energy
solutions for commercial and residential buildings. Integrated photovoltaic and solar thermal systems
outperform discrete systems in conversion efficiency and space utilization. There is a dearth of quantitative
comparative studies on these systems despite their functional similarities. This study offers a comparative
analysis of PV/T systems employing water and refrigerant as heat transfer fluids. Both systems are characterized
by identical size and collector design. Prototype development, experimental research, and parametric assessments
using computer models are used to attain this target. Furthermore, the design of the PV/T collector in this
research study involved the utilization of a double glass PV module instead of a tedlar back sheet PV module.
Based on ambient conditions, refrigerant-based PV/T systems can reach a final water temperature of 7 ◦C to
14.9 ◦C higher than water-based systems. In low irradiance conditions, the refrigerant-based system generates
hot water more reliably than the water-based system.
Solar Photovoltaic (PV) cells can absorb up to 80% of the incident solar radiation obtained from the solar band, however, only a small amount of this absorbed incident energy is transformed into electricity depending on the conversion efficiency of the PV cells and part of remainder energy increases the temperature of PV cell. High solar radiation and ambient temperature lead to an elevated photovoltaic cell operating temperature, which affects its lifespan and power output adversely. Number of techniques have been attempted to maintain the temperature of photovoltaic cells close to their nominal operating value. In the present review various cooling techniques such as natural and forced air cooling, hydraulic cooling, heat pipe cooling, cooling with phase change materials and thermoelectric cooling of PV panels are discussed at length. It is important to note that, though cooling techniques are highly needed to regulate the PV module temperature, especially for mega installations, these should be economically viable too.
In the traditional PV/T collector, the temperature of thermal energy is always limited by the operation temperature of PV cells. Such a low-temperature thermal energy can hardly meet the demand in industrial application. To breakthrough the temperature limitation, a concentrating PV/T collector with fluid-based spectral splitting filter is developed in present work. The oleylamine solution of Cu9S5 nanoparticle is adopted in the filter to harvest the moderate-temperature heat. The performance of the collector is investigated by an outdoor experimental system. The results indicate that the PV efficiency of Si cell itself can be improved when the Cu9S5 nanofluid is employed as the optical filter in the collector. The maximum overall efficiency of present PV/T collector is 34.2%, which is 17.9% higher than that without a filter. The present collector has successfully obtained thermal energy with a temperature higher than 100 °C, which verifies the potential of Cu9S5 nanoparticles in fluid-based spectral splitting technique. Moreover, the particle concentration has a significant influence on the performance of hybrid PV/T system. The ratio of heat to electricity in PV/T system can be adjusted by changing the particle concentration to meet the requirements in various applications. In addition, the glass cover surrounding outside of the optical filter can improve the thermal efficiency, but it also increases the optical loss of the system due to the reflection on the surface of glass. Therefore, to realize higher performance, it is necessary to employ the glass with anti-reflection layer in the collector.
Photovoltaic (PV) systems operate in a paradox; sunlight is the essential input to generate electricity with
PV, but they suffer a digression in performance as the operating temperature goes higher. This work is a
comprehensive compilation and review of the latest literature regarding research works rendered to
achieve improved efficiency through appropriate cooling systems. Most of the research goals were twofold,
that is to enhance the efficiency of the solar PV systems and to ensure a longer life at the same time.
The passive cooling systems are found to achieve a reduction in PV module temperature in the range of
6–20 �C with an improvement in electrical efficiency up to 15.5% maximum. On the other side, active
cooling systems’ performance are better, as may expected, with a reduction in PV module temperature
as high as 30 �C with an improvement in electrical efficiency up to 22% maximum along with additional
thermal energy output with efficiency reaching as high as 60%. Based on the wide-ranging review, it may
be predicted that with the swelling growth of solar PV electricity worldwide, the compatible cooling system
is becoming obligatory in order to ensure better energy harvest and utilization.
The flat plate photovoltaic thermal (PVT) collectors can be classified into the type of working fluids used namely the water based PVT collectors, air based PVT collectors and combination of water/air PVT collectors. However, low thermal conductivity of the working fluids has always been the primary limitation in the development of energy-efficient heat transfer fluids, and higher collector performance. To overcome this limitation, there is a strong motivation to improve the heat transfer of fluids with higher thermal conductivity. This new generation of heat transfer fluids called nanofluids consists of suspended nanoparticles and has higher suspension stability compared to the millimeter or micrometer size nanoparticles. Thus, the heat transfer characteristics will be enhanced by using nanofluids. The PVT collector has been designed, fabricated and tested outdoor under the Malaysia tropical climate conditions. The PVT collector consists of specially designed rectangular tube absorber (stainless steel material, height of 15 mm, width of 25 mm and thickness of 1 mm) attached under the photovoltaic module. The PVT collector was experimentally tested with different types of nanofluids (SiO2, TiO2 and SiC). The results indicated that the PVT collector with SiC nanofluid has the highest combined photovoltaic thermal (PVT) efficiency of 81.73% and PVT electrical efficiency of 13.52% with the best overall energy coefficient (COE) of 0.93 has been achieved at a flow rate of 0.170 kg/s and solar irradiance levels of 1000 W/m2, followed by PVT-TiO2 nanofluids, PVT-SiO2 nanofluids, and PVT-water respectively.
Photovoltaic/thermal (PV/T) solar systems, which produce both electrical and thermal energy simultaneously, represent a method to achieve very high conversion rates of sunlight into useful energy. In recent years, nanofluids have been proposed as efficient coolants and optical filter for PV/T systems. Aim of this paper is to theoretically analyze the life cycle exergy of three different configurations of nanofluids-based PV/T hybrid systems, and compare their performance to a standard PV and PV/T system. Electrical and thermal performance of the analyzed solar collectors was investigated numerically. The life cycle exergy analysis revealed that the nanofluids-based PV/T system showed the best performance compared to a standard PV and PV/T systems. At the optimum value of solar concentration C, nanofluid-based PV/T configuration with optimized optical and thermal properties produces ∼1.3 MW h/m2 of high-grade exergy annually with the lowest exergy payback time of 2 years, whereas these are ∼0.36, ∼0.79 MW h/m2 and 3.48, 2.55 years for standard PV and PV/T systems, respectively. In addition, the nanofluids-based PV/T system can prevent the emissions of about 448 kg CO2 eq m−2 yr−1. Overall, it was found that the nanofluids-based PV/T with optimized optical and thermal properties has potential for further development in a high-concentration solar system.