Renewable Energy, Vol.75, 722-732, 2015
Performance analysis of Azimuth Tracking Fixed Mirror Solar Concentrator
The fixed mirror solar collector (FMSC) fixes reflector and mobiles receiver to collect solar energy. However, this type of concentrator has a low efficiency and short operating duration in practical applications. In this paper, we propose to install the FMSC on an azimuth tracking device (ATFMSC) and the reflectors are arranged by intermission to avoid the shading of neighbor reflector for incidence angle of less than 10 degrees to improve its optical performance. Through the integration of the reflected solar radiation distribution function over any reflection point, and then the whole collector aperture, we develop the analytical expressions of various system efficiencies to numerically simulate the performance of ATFMSC with evacuated tube receiver in different design parameters. It is validated by the ray tracing results. The result shows that the mean annual net heat efficiency of the whole system would be up to 61% with the operating temperature of 400 degrees C, which is higher than parabolic trough collector and traditional FMSC This is because the longitudinal incidence angle of ATFMSC always remains zero by tracking the sun azimuth, so the end loss of the concentrator can be avoided and enables it to operate with high efficiency continually. (C) 2014 Elsevier Ltd. All rights reserved.
Keywords:Azimuth tracking;Fixed mirror solar collector;Mean annual net heat efficiency;Design parameters;Optical performance