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Summary: Photovoltaic thermal (PV/T) systems combine a hybrid photovoltaic (PV) module and a flat‐plate solar thermal collector. The hybrid design allows for simultaneou increase in thermal energy while providing cooling for the PV module. In doing so, the PV module temperature drops, and therefore the electrical efficiency increases. Another benefit of PV/T collectors is that they allow for the usage of thermal, and PV module in the same area and so that saved space for the consumer. This study presents a numerical (CFD) design and experimental evaluation of a PV/T system cooled by nano‐PCM and nanofluid. The selected nanomaterial and PCM were nano‐silicon carbide (SiC) and paraffin, respectively. Nano‐silicon carbide particles were employed with the paraffin to ameliorate its thermal conductivity. The study examined various aspects of the system such as the SiC particles' optimal mass fraction suspended in both water (base fluid) and paraffin, the optimum mass flow rate of nanofluid, voltage and current of the PV module, thermal energy of solar thermal collector, and the combined PV/T efficiency. The numerical and practical results were very close, which proves the validity of the hypotheses used in building the program. The significance of this study is demonstrated by the result as this design led to maximum thermal and electrical efficiencies of 72% and 13.7%, respectively. The proposed PV/T system introduced better stability of the generated power and thermal efficiency at peak time than the other two studied systems. [ABSTRACT FROM AUTHOR]

Summary: The use of photovoltaics has spread widely, and government agencies have begun adopting plans to deploy plants with large capacities, due to their environmental friendliness, low manufacturing costs, and high productivity. In the sunny countries where this technology should spread, the photovoltaics' energy conversion efficiency decreases due to the high temperature of which the cell's operate at; because a large part of the solar radiation is absorbed by the solar panels as heat, while the smaller part converts it to electricity. From here, the benefit of the shift towards the PV/T technology that works to reduce the photovoltaic modules temperature and improve their electricity produced along with yielded thermal energy which can be utilized in other applications. In this study, a thorough review of many recent research and studies published in the field of PV/T has been carried out. The present study was divided into several sections to clarify and focus on the effect of each technology separately. Researchers used one or more fluids to cool the solar panels, and their research dealt with many of these fluids, starting with air, water, oil, etc. Other researchers have tended to increase the thermal conductivity of liquid cooling fluids by adding many types of nanoparticles with high thermal conductivity. Other researchers have used variable‐phase materials to take advantage of the large storage of the latent heat of these materials. Other researchers have studied improving heat transfer of PCMs by mixing it with nanomaterials with high thermal conductivity. Others have also combined nano‐PCMs and nanofluids together in one system, and they have demonstrated, in theory and practice, that this technique exhibits higher energy collection and utilization than the other types of PV/T. At the conclusion of the study, some critical points are identified that work is still limited and needs more research efforts and studies. [ABSTRACT FROM AUTHOR]

The increase in the PV cell temperature ultimately causes a reduction in its effectiveness. One of the new methods used to retain that efficiency is to establish a hybrid photovoltaic thermal PV/T system. In this study, PCM has been employed with a cooling nanofluid circulation system in order to the control heat capacitance of the system to maintain electrical efficiency on the one hand, and to raise the overall efficiency on the other. Nano-SiC particles were used in paraffin-PCM and nanofluid to establish higher thermal conductivities and therefore higher efficiency. The design is tested outdoors in Selangor, Malaysia. The tests were conducted using a fluid flow rate of 0.17 kg/s. The proposed system reduced the cell temperature (30 °C) at the peak solar radiation period (12:30 AM to 1:30 PM), which was reflected positively on the PV/T system performance. The proposed PV/T-nano PCM-nanofluid system increased the open circuit voltage from 11–13 V to 20–21 V, the power from 61.1 W to 120.7 W, and the electrical efficiency from 7.1% to 13.7%. Besides, the system made use of the thermal energy gained as its thermal efficiency reached 72%. These results ensure the adequate use of the new design. [ABSTRACT FROM AUTHOR]