Performance investigation and optimization of the Trough Concentrating Photovoltaic/Thermal system

The overall performances of a 10 m2 Trough Concentrating Photovoltaic/Thermal (TCPV/T) system with a Super cell array, a GaAs cell array and a concentrating silicon cell array are investigated. The experimental results show that the average electrical efficiencies of the TCPV/T system with the three types of solar cell arrays are 3.63%, 8.94%, and 3.67% respectively in typical synoptic condition. The thermal efficiencies of the TCPV/T system with the three types of solar cell arrays are 45.17%, 41.69%, and 34.53% respectively after the TCPV/T system runs over 5 h. The TCPV/T system with the three types of cell arrays is also evaluated based on the electricity generation costs. From the point of the performance price ratio, the concentrating silicon cell array is preferable for the system with a middle or low concentration ratio.In order to improve the performance of the TCPV/T system, a 2 m2 experimental system utilizing the mirrors with a higher reflectivity is built. In concentrating irradiance, when the mirror reflectivity increases from 0.69 to 0.92, even the area of the reflecting mirrors reduce, the maximum powers of the cell arrays increase. The electrical efficiencies of the system using a Super cell array, a GaAs cell array and a concentrating silicon cell array rise by 0.9%, 2.62% and 5.47% respectively. The high reflectivity of the parabolic mirror is pursued. All these works are helpful to the further study on the trough concentrating system.