Numerical study of a covered Photovoltaic-Thermal Collector (PVT) enhancement using nanofluids

Numerical simulation of effect of non-uniform solar irradiation on nanofluid turbulent flow

Performance analysis of hybrid/single nanofluids on augmentation of heat transport in lid-driven undulated cavity

Due to the increasing demand for energy in the world and the problems caused by fossil fuels, the use of renewable energy has become the focus of governments. Therefore, the study and use of renewable energy, especially solar energy, is an essential development program for all governments. There are massive efforts to increase the efficiency of photovoltaic (PV) technology which is rapidly developing, in order to decrease the capital cost of a solar power plant. In this paper, two methods for enhancing the efficiency of PV modules are considered: using phase change material (PCM) as coolant and integrating reflectors. The experiments were performed in Dezful, Iran, with very hot summers. The results show that, using reflector boosts the received irradiation by the PV panel, but at the same time, leads to increase the PV module temperature. Therefore, using PCM in order to decrease the temperature is justified. Among different tilt angles of the mirror, 30° presents the best outcomes. Then, this case was tested with one additional mirror on top of the PV module. So, the case of double mirrors was selected and bring about 4.1 % improvement in electrical output, in comparison with the conventional one. As the next stage, this optimum case was repeated by utilizing the PV module with PCM at its back side. 12.5 % enhancement of electrical output and 24 % reduction in entropy generation were calculated, in comparison with the conventional one. 

Experimental study on simultaneous use of phase change material and reflector to enhance the performance of photovoltaic modules

Conversion of light into electricity is possible by means of photovoltaic (PV) technology. The negative impact of increasing the temperature of PV cells on their output power is one of the most important weaknesses of this technology. In this experimental study, a porous medium integrated with phase change material (PCM) as two passive cooling methods of PV modules are employed and their effects on cooling the PV panel are investigated, either separately or simultaneously. Two thickness values of the aluminum porous medium were mounted at the back side of PV module. The results show that a 2 cm thick porous medium reduces the module temperature by 14.5 °C, while when PCM is added, the temperature drop reaches 21.5 °C compared to a conventional PV module. Moreover, adding PCM, downgrades the rate of temperature rise. Increasing the output power due to the use of PCM and porous media, causes 18.6 % less PV modules to run a 10-kW photovoltaic power plant. The entropy generation of the system was also calculated and 4 % difference between the mentioned cases was calculated. An important concern about the thermal exergy assessment is discussed in details. 

Simultaneous use of porous medium and phase change material as coolant of photovoltaic modules; thermodynamic analysis

Photovoltaic (PV) module is one of the most useful, sustainable and non-harmful products in the field of renewable energy. It offers longer service period for least maintenance cost. The elements of PV are abrasive, easy for designing, and their structure like the stand-alone technique gives production from micro to mega-power level. A 3D numerical system of PV module has been built up and solved applying FEM technique-based software COMSOL Multiphysics in this article. The average solar irradiation and optimum tilt angle for six divisions (Dhaka, Chittagong, Rajshahi, Khulna, Barishal and Sylhet) in Bangladesh have been calculated. The effects of solar radiation, angle of inclination, ambient temperature, and partial shading on temperature of solar cell, electrical power and PV module's electrical efficiency have been investigated. It has been observed from the results that the greatest value of electrical power 15.14 W is found in Rajshahi for solar radiation 209 W/m2. The highest electrical efficiency is found as 12.85% in Sylhet at irradiation level of 189 W/m2. For every 1° increase of inclination angle, electrical power and electrical efficiency level devalue by 0.06 W and 0.05%, respectively. Results also show that the efficiency level decreases from 14.66 to 11.32% due to partial shading area from 0 to 40%. PV module's electrical power; and electrical efficiency reduces approximately 0.01 W and 0.01%, respectively due to every 1°C addition of solar cell temperature.

https://jcarme.sru.ac.ir/article_1179_be1b96b7e28a6a88abab984c7660407c.pdf

Numerical analysis of photovoltaic power generation in different locations of Bangladesh

Electrical power as well as thermal energy are converted from solar radiation in a photovoltaic thermal (PVT) system. At a fixed temperature, thermal energy is absorbed by phase change materials (PCM) in terms of latent heat. PCM has storage ability of latent heat. The heat is stored in PVT/PCM system and used latterly as an ultimate application. For PVT/PCM system heat removal procedure is concurrent due to the dependence of its charging and discharging on ambient. In this research, a 3D mathematical model of PVT/PCM system has been solved numerically using finite element method. Results have been shown in terms of surface temperature and streamline pattern of PVT/PCM system with time variation. The values of average temperature of solar cell, electrical power, heat energy, electrical-thermal efficiency and overall efficiency have been found. It is observed that using PCM in the PVT module the temperature of solar cell reduces and consequently the output power and efficiency enhance.

3D study of heat transfer based on PVT/PCM system

The most popular renewable energy source is solar energy, which characterises as free, clean, and environmentally friendly. Photovoltaics (PV) generate electricity from daylight, becoming increasingly popular in residential and other applications. The potential energy delivery from a photovoltaic module is a function of solar radiation falling on the front surface and module operating temperature. However, these systems are modified to improve energy generation by placing an absorber on the bottom side of the module termed a Photovoltaic Thermal (PVT) system to reduce module temperature. The current study aims to investigate the experimental heat transfer efficiency for the fabricated PVT system employing two-sided serpentine flow thermal absorber and phase change material (PCM). PCM discharge the latent heat during off-sunshine hours to provide additional hot water. The experiment setup was tested with water as a working fluid in the flow rate range of 0.0085–0.067 kg/s. The optimal flow rate at which maximum heat gain of 757 W was obtained 0.033 kg/s with an average energy-saving efficiency of 69 %. The results confirm enhanced energy delivery of 3–5 % by PVT-PCM system compared to reference PV module for the same ambient operating conditions. Furthermore, the study reveals that overall efficiency of the PVT setup augment with the use of a thermal absorber and PCM, while the thermal efficiency is a factor that depends on the working fluid properties. • Fabrication of a two-side serpentine flow absorber for cooling photovoltaic thermal-phase change material collector system. • Results from heat transfer analysis lead to higher heat removal at 0.033 kg/s fluid flow rate of water. • Overall and energy-saving efficiency enhance by 23% and 28% for water flow rate of 0.033 kg/s as compared to other flow rates. • As the water flow rate increases from 0.0085 kg/s to 0.033 kg/s, the panel maximum average power output gains by 3%. 

Thermal analysis of hybrid photovoltaic-thermal water collector modified with latent heat thermal energy storage and two side serpentine absorber design

M. Saddam Hossain

Papers

Numerical analysis of photovoltaic power generation in different locations of Bangladesh

3D study of heat transfer based on PVT/PCM system

Thermal analysis of hybrid photovoltaic-thermal water collector modified with latent heat thermal energy storage and two side serpentine absorber design

The role of electric vehicles in decarbonizing India's road passenger toward carbon neutrality and clean air: A state-level analysis