5 research outputs found
Performance Comparison of the Standard Photovoltaic Thermal Collector (PVT) and Photovoltaic Thermal Collector with Phase Change Materials (PVT-PCM)
The purpose of this study is to evaluate the thermal and electrical efficiency of PVT-PCM and PVT for photovoltaic thermal collectors. A square absorber tube with PCM was utilized in the study, introducing a new approach to photovoltaic thermal collectors. COMSOL computational fluid dynamics (CFD) software was employed to carry out the simulations, and the tests were conducted as indoor experiments in a lab. Water was used as the transmission fluid in this study. Different volume flow rates ranging from 1–3 LPM were assessed for both experiment and simulation by considering the radiation range of 400, 600, and 800W/m2 . At a volume flow rate of 2 LPM, experimental results showed that PVT-PCM achieved higher electrical and thermal efficiencies of 9.95% and 88.3%, respectively, compared to the simulation results of 10.0% and 86.5%. Comparable outcomes were seen with both the simulation and experiment
Classification of Jet Impingement Solar Collectors – A Recent Development in Solar Energy Technology
Jet impingement mechanism has been extensively studied in previous research due to its ability to enhance the efficiency of a solar collector. The photovoltaic module temperature can be effectively lowered while preserving the temperature uniformity and enhancing the solar collector performance. Since jet impingement offers such a broad application, numerous studies have focused on its heat transfer characteristic. This article provides a comprehensive review of recent jet impingement solar collectors. Additionally, the design and performance of the jet impingement cooling methods on solar air collectors, photovoltaic and photovoltaic thermal systems are discussed. The comprehensive review is classified into four main components involving jet impingement in solar collector applications: single pass, double pass, concentrated and jet configuration. A critical review is discussed at the end of each classification. The nozzle streamwise and spanwise pitch, nozzle to target spacing, nozzle diameter, nozzle shape, and Reynold number significantly impact the heat transfer properties of jet impingement. Research on applying single pass-single ducts using jet impingement is still lacking and needs further research. Thermally, a double passsolar collector outperforms a single pass-solar collector due to the absorber plate's high heat extraction rate and more significant interaction caused by the doubled heat transfer surface
Heat Transfer Performance of a Novel Circular Flow Jet Impingement Bifacial Photovoltaic Thermal PVT Solar Collector
Jet impingement is commonly used to enhance the performance of solar collectors by improving the heat transfer rate. This paper presents a Novel Circular Flow Jet Impingement applied to a bifacial photovoltaic thermal (PVT) solar collector. The energy performance of the PVT solar collector was analyzed using CFD COMSOL simulation. The circular flow cup was attached to the jet plate with 36 jet plate holes and streamwise pitch, X = 113.4mm, and spanwise pitch, Y= 126mm. The inlet circular cup diameter of 6mm and outlet jet plate hole of 3mm are used to promote impinging jet effects on the photovoltaic module. The mass flow rate ranges between 0.01-0.14kg/s, and Reynolds number ranges between 2,738-14,170 to promote turbulent flow. The swirling and diffusive properties of turbulence enhance the heat transfer rate. The study was conducted to analyze two distinct scenarios: the first sought to identify the optimal diameter size, and the second sought to determine the optimal depth for the circular cup. Each model was tested with a solar irradiance ranging from 600W/m2 to 900W/m2 . The optimum design for the Circular Flow Jet Impingement was achieved using a 40mm diameter and 20mm depth with a maximum photovoltaic, thermal, and overall efficiency of 63%, 11.09% and 74.09% at an irradiance of 900W/m2 and flow rate of 0.14kg/s
The effect of a reversed circular jet impingement on a bifacial module PVT collector energy performance
Photovoltaic thermal (PVT) technologies have a significant downside in addition to their numerous advantages. PVT technologies are constrained by the fact that its photovoltaic module gains heat due to exposure to solar irradiance, which reduces the photovoltaic efficiency. Jet impingement is one of the most effective methods to cool a photovoltaic module. An indoor experiment using a solar simulator was conducted on a bifacial PVT solar collector cooled by a reversed circular flow jet impingement (RCFJI) to evaluate the energy performance of the PVT collector. The study was conducted under a constant solar irradiance of 900W/m2 and flowrate (mass) ranging from 0.01 to 0.14 kg/s. Three bifacial modules with 0.22, 0.33, and 0.66 packing factors were mounted 25 mm above the RCFJI for cooling. The 0.66 packing factor module recorded the highest photovoltaic efficiency of 10.91 % at 0.14 kg/s flowrate (mass). Meanwhile, the 0.22 and 0.33 packing factors recorded a photovoltaic efficiency of 4.50 % and 6.45 %, respectively. The highest thermal efficiency recorded under the same operating condition was 61.43 %, using a 0.66 packing factor. Overall, the highest combined photovoltaic thermal (PVT) efficiency for 0.22, 0.33, and 0.66 was 56.62 %, 61.88 %, and 72.35 %, respectively
Performance and economic analysis of a reversed circular flow jet impingement bifacial PVT solar collector
As the world shifts towards a more sustainable future, solar energy has emerged as a preeminent and economically feasible alternative to traditional energy sources, gaining widespread adoption. This study presents a reversed circular flow jet impingement (RCFJI) which aims to improve the performance of a bifacial PVT collector. An indoor experiment using a solar simulator to assess the energy, exergy, and economic efficiency of a RCFJI bifacial PVT collector. The study was carried out using a solar irradiance ranging from 500-900W/m2 and a mass flow rate between 0.01-0.14 kg/s. Energy performance-wise, the highest photovoltaic efficiency achieved was 11.38% at solar irradiance of 500 W/m2, while the highest thermal efficiency achieved was 61.4% under 900 W/m2, both obtained at 0.14 kg/s mass flow rate. Regarding exergy performance, the highest photovoltaic exergy obtained was 47.27 W under 900 W/m2 at 0.14 kg/s, while the highest thermal exergy was 9.67 W at 900 W/m2 at 0.01 kg/s. Overall, higher solar irradiance is more desirable for energy and exergy performance. Meanwhile, economic point of view, lower solar irradiance is preferable. Based on the findings, the optimal mass flow rate was 0.06 kg/s