Applied Mechanics and Materials Vols. 448-453

Abstract: The solar energy as a kind of new clean energy, plays an important role in the economic development and protecting environment in China1China started later in the exploitation and utilization of solar energy, but has big solar potential. This paper gives a detailed introduction to the distribution of solar energy resources, and the industrial utilization of solar light-heat effect and light-electricity, points out the prospects of the development of solar energy industry in China.

Abstract: The output powers of photovoltaic (PV) system are crucially depending of the two variable factors, which are the cell temperatures and solar irradiances. A method to utilize effectively the PV is known as a maximum power point tracking (MPPT) method. This method is extract the maximum available power from PV module by making them operates at the most efficient output. This paper presents Radial Basis Function (RBF) Network to control the MPPT of PV system. The performances of the controller is analyzed in four conditions with are constant irradiation and temperature, constant irradiation and variable temperature, constant temperature and variable irradiation, and variable temperature and irradiation. The proposed system is simulated by using MATLAB-SIMULINK. According to the results, RBF controller has shown better performance during partially shaded conditions.

Abstract: A modeling method of single-phase grid-connected photovoltaic micro-inverter is presented in this paper,which depends on the topology structure of fly-back converter. Simulation of the micro-inverter is performed using Matlab software, which has the virtues of high accuracy and fast speed. Prototype experiment results show that the simulation model can be a true reflection of the working process of a micro-inverter, and could be used to verify the control algorithm and select the control parameters.

Abstract: Although the Chinese solar semiconductor lighting industry has been developing rapidly, the detecting technology of this has developed slowly. Therefore, the performance testing device of solar lighting system would be practical significant. In view of this, this paper was mainly using the Hall current sensor, USB data acquisition card and other components to build a solar lighting system detection device. During the actual testing, the system can monitor and evaluate the real-time performance of the photovoltaic street lighting system very well, and achieves the desired effect.

Abstract: The energy yield of PV system with different material, declination angle and land covering ratio are presented. Comparisons are made between two Chinese cities, Beijing and Nanjing. Shading effects are also investigated for the PV systems energy yield calculation. It shows that by neglecting the losses due to weather and the temperature effects, for the location with higher latitude (such as Beijing) the PV system installed with double junction solar cells (micromorph silicon) is predicted to have lower Performance Ratio than that with mono-crystalline silicon and multi-crystalline silicon. An optimum row spacing of a PV system should be considered for limited occupation area. The criteria above are important for large scale PV system design and its efficiency maximization. The simulation is useful to predict the power fluctuation delivered by PV system due to the spectral, seasonal variation and geometry difference.

Abstract: This work reports on the analysis of thin-film copperindiumgalliumdiselenide (CIGS) solar cells by using Solar Cell Capacitance Simulator software (SCAPS). We have modeled a PV device, which consists in a CIGS absorber, a CdS buffer and a ZnO window layer. We have studied the behavior of CIGS absorber as a function of Gallium content by simulating the behavior of CIGS solar cells versus the Ga content in the absorber layer.

Abstract: Photovoltaic and photo-thermal integration PV/T system can efficiently produce heat using solar energy as well as generate electricity in a large scale. Based on the comparison test of solar efficiency between PV/T system with heat pipe cooling and tube plate PV/T system, whereas get the advantage for different PV/T systems in solar utilization.

Abstract: A solar thermal organic Rankine cycle (ORC) power generation system model established using R245fa as the working fluid and coupled with a solar photovoltaic generator is introduced. Thermal efficiency and exergy efficiency of the model both with and without a heat regenerator are calculated and compared. Results show the solar organic Rankine cycle system with a heat regenerator has higher thermal and exergy efficiency than the system without a heat regenerator, providing better performance in practice. This result provides a basis for further application and improvement of solar photovoltaic and the solar thermal organic Rankine cycle.

Abstract: The selection criteria of working fluids for solar thermal organic Rankine cycle and the features of R245fa as a working fluid are analyzed. A thermodynamic analysis of photovoltaic / thermal organic Rankine cycle system and the influence of evaporation temperature of working fluid in the evaporator coupled with solar panels are conducted. The results show that the performance of the solar photovoltaic/thermal organic Rankine cycle can be improved by optimizing the evaporation temperature, and 130°C is an appropriate evaporation temperature.

Abstract: The solar ponds with a surface of 0.3m² were filled with different concentration salt water and fresh water. The three layer’s structure of solar ponds was formed in the laboratory ponds by using the salinity redistribution. The performance and diffusion of salinity were xperimentally in the solar pond. The measurements were taken and recorded daily at various locations in the salt-gradient solar pond during a period of 30 days of experimentation. The experimental results showed that the salinity gradient layer can sustain a longer time when the lower convective zone is thicker, which is benefit to store solar energy. Therefore, properly increasing the height of LCZ is a good method to enhance the solar pond performance.