Method for Predicting Thermoelectric Module Efficiency Using MATLAB/Simulink

Development new high-performance thermoelectric materials for more efficient power generation systems and eco-friendly refrigerating systems has been challenging. Over the past few decades, thermoelectric studies have been focused on increasing the thermoelectric properties of materials. However, for conventional applications, developing of thermoelectric devices or modules with lower cost and simpler fabrication processes is also important. Simulation models that can predict the thermoelectric efficiency of modules using the thermoelectric properties of materials are needed for this purpose. In this study, we developed a simple model for calculating the efficiency of thermoelectric modules using MATLAB/Simulink. In this model, the temperature difference between the hot source and heat sink was fixed to ensure the precise comparisons of thermoelectric efficiency. The electric resistivity and Seebeck coefficient of thermoelectric materials was used in order to predict the efficiency of the thermoelectric modules. Then, the efficiency of the thermoelectric modules was verified using measured values which had been reported in prior experimental works. In this study, the simulated values were higher than the real thermoelectric effiency values. To address this, the simulations should consider the thermal resistance or electric contact resistance between the thermoelectric materials and electrodes.

Adaptive centrifuge vibration damping module for biofuel production

The present study considers the problem of obtaining promising renewable energy sources, in particular biofuel. Biomass is the main fuel for green energy accounting for two-thirds of renewable energy. Industry further development depends on improvement of used equipment and technologies. Biofuel usually contains significant amounts of harmful impurities that need to be isolated. The paper deals with the problems of centrifuge operation for the biofuel production. In particular, the most significant operation problem is the residual rotor imbalance which causes torsional oscillations that negatively affect the biodiesel production process and centrifuge reliability. A new technology for damping torsional vibrations of centrifugal device rotating system is described as well as adaptive module device for its implementation is developed. The module main feature is vibrations adaptive level of the rotor elements interaction with external environment. Computer simulation of the module operation process in ANSYS Fluent program was carried out. Data on the module efficiency depending on various factors in the dynamics of its work are obtained. The most effective device configuration is determined.

PVcheck—A Software to Check Your Photovoltaic System

Having a photovoltaic (PV) system raises the question of whether it runs as expected. Measuring its energy yield takes a long time and the result still contains uncertainties from varying weather conditions and possible shading of the modules. Here, a free software PVcheck to measure the peak power of the system is announced, using the power data of a single sunny day. The software loads a data file of the generated power as a function of time from this day. This data file is provided by typical inverters. The software then simulates this power curve using known parameters like angle and location of the PV system. The assumed peak power of the simulation can then be adjusted so that the simulated curve matches the measured one. The software runs under Microsoft Windows™ and makes use of the free library pvlib python. The simulation can be refined by importing weather data like temperature, wind speed, and insolation. Furthermore, curves describing the nominal module efficiency as a function of the illumination intensity as well as the power-dependent inverter efficiency can be included in the simulation. First results reveal a good agreement of the simulation with experimental data. The software can be used to detect strong problems in PV systems after installation and to monitor their long-time operation.

TEMPERATURE AND IRRADIANCE BASED ANALYSIS THE SPECIFIC VARIATION OF PV MODULE

The effect of irradiance and increase of temperature on the back surface of the PV module would decrease the standardized efficiency of PV. To overcome this problem observed results of solar module (ORSM) and Newton Raphson’s (iterative) methods have been proposed in this research. This article compares ORSM and iterative methods of changing the specifications of a single diode model (SDM) extracted from a PV module beneath standard test conditions (STC) to calculate irradiance and various operating conditions. To make this comparison, the exact value of each diode parameter on the STC is essential. These are achieved by accepted algebraic values and iterative techniques. Newton Raphson’s technique has been proven to be the mainly precise method to find these specifications in STC. Therefore, these specifications are used to different techniques that change the parameters of an SDM with radiation and temperature. The MATLAB model is designed to assess the conducting of individual techniques by PVM. The results are compared with the measured data, and the accuracy of photovoltaic module efficiency has been achieved through different technologies at different temperature and insolation levels.

Controlled Photoanode Properties for Large-Area Efficient and Stable Dye-Sensitized Photovoltaic Modules

Nowadays, a dye-sensitized solar cell (DSSC) attracts attention to its development widely due to its several advantages, such as simple processes, low costs, and flexibility. In this work, we demonstrate the difference in device structures between small size and large size cells (5 cm × 5 cm, 10 cm × 10 cm and 10 cm × 15 cm). The design of the photoanode and dye-sensitized process plays important roles in affecting the cell efficiency and stability. The effects of the TiO2 electrode, using TiCl4(aq) pretreatment and post-treatment processes, are also discussed, whereas, the open-circuit voltage (Voc), short-circuit current density (Jsc), and module efficiency are successfully improved. Furthermore, the effects on module performances by some factors, such as dye solution concentration, dye soaking temperature, and electrolyte injection method are also investigated. We have demonstrated that the output power of a 5 cm × 5 cm DSSC module increases from 86.2 mW to 93.7 mW, and the module efficiency achieves an outstanding performance of 9.79%. Furthermore, enlarging the DSSC modules to two sizes (10 cm × 10 cm and 10 cm × 15 cm) and comparing the performance with different module designs (C-DSSC and S-DSSC) also provides the specific application of polymer sealing and preparing high-efficiency large-area DSSC modules.

Investigating the Effect of Inclination Angle of Magnetic Field Vector on Silicon PV Modules

In earlier studies, we have shown theoretically and experimentally that magnetic fields (MFs) have negative impact on silicon PV module (photovoltaic module). A noticeable decline in photocurrent with a slight increase in photovoltage was observed. Also, how those fields affected other key module’s parameters was also studied. These studies concluded that an increase in the magnitude of the MF resulted in the decrease of the efficiency of the silicon PV module. The previous experimental studies assumed that the MF vector formed zero angle of inclination with respect to the photosensitive face of the module. They did not factor in any effect that could be observed when the field vector is inclined. The present experimental work is an attempt to fill that gap. The characteristic curves of the PV module were plotted in the same system of axis for different values of the inclination angle of the MF vector. Correspondingly, the characteristic values ( P max , I max , V max , I sc , and V oc ) of the PV module were also determined. These parameters then allowed the calculation of the efficiency of the module, its fill factor, and the equivalent circuit series and shunt resistances. It is observed that the module efficiency increases with the inclination of the MF vector, indicating that the effect of the MF on the PV module is reduced when its vector aligns towards a direction that is perpendicular to the base of the module. For example, when α moves from 0 to 90°, the power output and consequently the efficiency of the PV module relatively increase of 14%.