scholarly journals Experimental Investigation of a Novel Absorptive/Reflective Solar Concentrator: A Thermal Analysis

Energies ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1281 ◽  
Author(s):  
Alok Dayanand ◽  
Muhsin Aykapadathu ◽  
Nazmi Sellami ◽  
Mehdi Nazarinia

This paper presents the experimental investigation of a novel cross-compound parabolic concentrator (CCPC). For the first time, a CCPC module was designed to simultaneously work as an electricity generator and collect the thermal energy present in the module which is generated due to the incident irradiation. This CCPC module consists of two regions: an absorber surface atop the rig and a reflective region below that to reflect the irradiation onto the photovoltaic (PV) cell, coupled together to form an absorptive/reflective CCPC (AR-CCPC) module. A major issue in the use of PV cells is the decrease in electrical conversion efficiency with the increase in cell temperature. This module employs an active cooling system to decrease the PV cell temperature, optimizing the electrical performance and absorbing the heat generated within the module. This system was found to have an overall efficiency of 63%, which comprises the summation of the electrical and thermal efficiency posed by the AR-CCPC module.

2017 ◽  
Vol 139 (3) ◽  
Author(s):  
Afroza Nahar ◽  
M. Hasanuzzaman ◽  
N. A. Rahim

Performance of photovoltaic (PV) module decreases significantly with increasing cell temperature due to its overheating. Photovoltaic thermal (PVT) is an optimized technology that facilitates effective removal and utilization of this excess heat leading to enhanced electrical performance. In this article, a 3D numerical model has been developed and analyzed to investigate the PVT performance with a new pancake-shaped flow channel design. This flow channel is attached directly to the backside of PV module by using thermal paste. The governing equations are solved numerically by using Galerkin's weighted residual finite-element method (FEM), which has been developed using COMSOL Multiphysics® software. The numerical results show that the cell temperature reduces on an average 42 °C, and the electrical efficiency and output power increase by 2% and 20 W, respectively, for both aluminum and copper channels with an increase in inlet velocity from 0.0009 to 0.05 m/s. On the other hand, overall efficiency of the PVT system drops about 13% in both cases as the inlet temperature increases from 20 °C to 40 °C. Cell temperature is found to increase approximately by 5.4 °C and 9.2 °C for every 100 W/m2 increase in irradiation level of the PV module with and without cooling system, respectively. Regarding flow channel material, it has been observed that use of either copper or aluminum produces almost similar performance of the PVT module.


2021 ◽  
Author(s):  
Srimanickam Baskaran ◽  
Christopher Sathiya Satchi ◽  
Saranya Amirtharajan ◽  
Metilda Manuel Swami Durai

Abstract Increasing surface temperature significantly affects the electrical performance of photovoltaic (PV) panels. A closed-loop forced circulation serpentine tube design of cooling water system is used to effectively manage the surface temperature of PV panels. A real-time experiment was first carried out with a PV panel with a cooling system at HTF flow rates of 60 kg h-1, 120 kg h-1, and 180 kg h-1. Based on the experimentation, a correlation for a nominal operating cell temperature (NOCT) and thermal efficiency for collector was developed for experimental validation of useful energy gained, cell temperature and electric power generation. The developed corrections are validated with electrical power and useful energy gained in photovoltaic serpentine thermal solar collector (PV/STSC) and fit into experimental results with a deviation of 1% and 2.5 % respectively. Further, with the help of developed correlations, a system was developed in the TRNSYS tool through which an optimization study was performed based on electric and hot water demand. The findings indicate that an optimal system with an 8 m2 PV/STSC area, a HTF flow rate of 60 kg h-1, and TES system having a volume and height of 280 l and 0.8 m could meet 91 % and 33 % of the hot water demand for Ac loads and 78 % or DC loads, respectively.


2020 ◽  
Vol 4 (41) ◽  
pp. 51-56
Author(s):  
DMITRIY STREBKOV ◽  
◽  
NATAL’YA FILIPPCHENKOVA ◽  

In the field of energy supply to agro-industrial facilities, there is an increasing interest in the development of structures and engineering systems using renewable energy sources, including solar concentrator thermal and photovoltaic modules that combine photovoltaic modules and solar collectors in one structure. The use of the technology of concentrator heat and photovoltaic modules makes it possible to increase the electrical performance of solar cells by cooling them during operation, and significantly reduces the need for centralized electricity and heat supply to enterprises of the agroindustrial complex. (Research purpose) The research purpose is in numerical modeling of thermal processes occurring in a solar concentrator heat-photovoltaic module. (Materials and methods) Authors used analytical methods for mathematical modeling of a solar concentrator heat and photovoltaic module. Authors implemented a mathematical model of a solar concentrator heat and photovoltaic module in the ANSYS Fluent computer program. The distribution contours of temperature and pressure of the coolant in the module channel were obtained for different values of the coolant flow rate at the inlet. The verification of the developed model of the module on the basis of data obtained in an analytical way has been performed. (Results and discussion) The results of comparing the calculated data with the results of computer modeling show a high convergence of the information obtained with the use of a computer model, the relative error is within acceptable limits. (Conclusions) The developed design of the solar concentrator heat and photovoltaic module provides effective cooling of photovoltaic cells (the temperature of photovoltaic cells is in the operating range) with a module service life of at least twenty-five years. The use of a louvered heliostat in the developed design of a solar concentrator heat and photovoltaic module can double the performance of the concentrator.


2014 ◽  
Vol 63 (1) ◽  
pp. 419-427 ◽  
Author(s):  
Xiangjie Chen ◽  
Mark Worall ◽  
Siddig Omer ◽  
Yuehong Su ◽  
Saffa Riffat

Designs ◽  
2018 ◽  
Vol 2 (3) ◽  
pp. 29
Author(s):  
Muhsin Aykapadathu ◽  
Mehdi Nazarinia ◽  
Nazmi Sellami

A crossed compound parabolic concentrator (CCPC) is a non-imaging concentrator which is a modified form of a circular 3D compound parabolic concentrator (CPC) obtained by orthogonal intersection of two 2D CPCs that have an optical efficiency in line with that of 3D CPC. The present work is about the design and fabrication of a new generation of solar concentrator: the hybrid photovoltaic (PV)/thermal absorptive/reflective CCPC module. The module has a 4× CCPC structure truncated to have a concentration of 3.6× with a half acceptance angle of 30°. Furthermore, an experimental rig was also fabricated to test the performance of the module and its feasibility in real applications such as building-integrated photovoltaic (BIPV). 3D printing and Computer Numerical Control (CNC) milling technologies were utilized to manufacture the absorber and reflective parts of the module.


2012 ◽  
Vol 134 (3) ◽  
Author(s):  
Véronique Delisle ◽  
Michaël Kummert

Combined photovoltaic/thermal (PV/T) collectors show great potential for reaching the objective of net-zero energy consumption in buildings, but the number of products on the market is still very limited. One of the reasons for the slow market uptake of PV/T collectors is the absence of standardized methods to characterize their performance. Performance characterization is a challenge for PV/T collectors because of the interaction between the thermal and electrical yield. This study addresses this particular issue for PV/T air collectors used in either closed-loop or open-loop configurations. In particular, it presents the potential of the equivalent cell temperature method to determine the temperature of the PV cells in a PV/T air collector and validates models to predict the thermal performance and cell temperature for this particular type of solar collector. Indoor and outdoor experimental tests were performed on two c-Si unglazed PV/T modules. The indoor part of this procedure provided the thermal diode voltage factor and the open-circuit voltage temperature coefficient, two parameters that are essential in the calculation of the equivalent cell temperature. The outdoor procedure consisted of acquiring simultaneous electrical and thermal measurements at various inlet temperatures and flowrates. For the collector used in a closed-loop configuration, thermal efficiency models using the fluid inlet, outlet, or average temperature in the calculation of the reduced temperature provided similar results. For an open-loop configuration, a thermal efficiency model as a function of the fluid outlet flowrate was found to be more appropriate. Using selection of variable methods, it was found that a multiple linear regression model using the fluid inlet temperature, the irradiance, and the fluid outlet temperature as predictive variables could be used to estimate both the PV module back surface average temperature and the equivalent cell temperature. When using the PV temperature predicted by these models in the electrical efficiency model, both PV temperatures showed similar performance. In collectors where the PV back surface temperature is not accessible for temperature sensors mounting, the equivalent cell temperature provides a valuable alternative to be used as the PV temperature. The PV/T collector thermal and electrical performance in either closed-loop or open-loop configurations was found to be encapsulated with a series of five-plots.


Author(s):  
A. G. Agwu Nnanna ◽  
Erik Rolfs ◽  
James Taylor ◽  
Karla Ariadny Freitas Ferreira

Design and development of energy efficient vehicles is of paramount importance to the automobile industry. Energy efficiency can be enhanced through recovery of the kinetic energy lost in the form of waste heat during braking. The kinetic energy could be converted into a reusable energy source and aid in acceleration, hence the braking system would contribute to improving the overall efficiency of a vehicle. Hydraulic-Pneumatic Regenerative Braking (HPRB) systems are a hybrid drive system that works in tandem with a vehicle’s engine and drivetrain to improve efficiency and fuel-economy. A HPRB system functions by recovering the energy typically lost to heat during vehicle braking, and storing this energy as a reusable source that can propel a vehicle from a stop. The major advantages of a HPRB system are that a vehicle would not require its engine to run during braking to stop, nor would the engine be required to accelerate the vehicle initially from a stop. The benefit realized by this system is an increase in fuel-efficiency, reduced vehicle emissions, and overall financial savings. An HPRB system aids in slowing a vehicle by creating a drag on the driveline as it recovers and stores energy during braking. Therefore, HPRB system operation reduces wear by minimizing the amount of work performed by the brake pads and rotors. An experimental investigation of Hydraulic-Pneumatic Regenerative Braking (HPRB) system was conducted to measure the system’s overall efficiency and available power output. The HPRB in this study is a 1/10th lab-scale model of a light-duty four wheel vehicle. The design/size was based on a 3500 lbs light-duty four wheel vehicle with an estimated passenger weight of 500 lbs. It was assumed that the vehicle can accelerate from 0–15 mph in 2 seconds. The aim of this work is to examine the effect of heat losses due to irreversibility on energy recovery. The experimental facility consisted of a hydraulic pump, two hydraulic-pneumatic accumulators, solenoid and relief valves, and data acquisition system. The HPRB system did not include any driveline components necessary to attach this system onto a vehicle’s chassis rather an electric motor was used to drive the pump and simulate the power input to the system from a spinning drive shaft. Pressure transducers, Hall effects sensor, and thermocouples were installed at suction and discharge sections of the hydraulic and pneumatic components to measure hydrodynamic and thermos-physical properties. The measured data were used to determine the system’s energy recovery and power delivery efficiency. Results showed that the HPRB system is capable of recovering 47% of the energy input to the system during charging, and 64% efficient in power output during discharging with an input and output of 0.33 and 0.21 horsepower respectively. Inefficiencies during operation were attributed to heat generation from the gear pump but especially due to the piston accumulator, where heat loss attributed to a 12% reduction in energy potential alone.


Author(s):  
Allison Gray ◽  
Robert Boehm ◽  
Kenneth W. Stone

Cooling of photovoltaic cells under high intensity solar irradiance is a major concern when designing concentrating photovoltaic systems. The cell temperature will increase if the waste heat is not removed and the cell voltage/power will decrease with increasing cell temperature. This paper presents an analysis of the passive cooling system on the Amonix high concentration photovoltaic system (HCPV). The concentrator geometry is described. A model of the HCPV passive cooling system was made using Gambit. Assumptions are discussed that were made to create the numerical model based on the actual system, the methods for drawing the model is discussed, and images of the model are shown. Fluent was used to compute the numerical results. In addition to the theoretical results that were computed, measurements were made on a system in the field. These data are compared to the theoretical data and differences are calculated. Theoretical conditions that were studied included uniform cell temperatures and worst case weather scenarios, i.e., no wind, high ambient conditions, and high solar irradiance. The performance of the Amonix high concentrating system could be improved if more waste heat were removed from the cell. Now that a theoretical model has been developed and verified, it will be used to investigate different designs and material for increasing the cooling of the system.


Sign in / Sign up

Export Citation Format

Share Document