The effects of light intensity and collector surface on the performance of a solar thermal collector

In this research paper, an attempt has been made to unearth the effects of light intensity and collector surface on the efficiency of a solar thermal collector. Experiments were performed using a solar energy demonstration system (ET 200). This system comports a collector, a storage tank, a high power lamp simulating solar energy and a control and command cabinet. The increase of the light intensity from 1043,12 to 2649,10 W/m² increased the effectiveness of the collector. In deed, the light intensity is related to the efficiency of the solar collector with an exponential relationship showing a coefficient of determination (R²) of 0.926. For radiation intensity of 885 W/m², flow rate of 8 l/h , total surface of 0,138 m² and an inclination angle of 0°, the results showed that the efficiency of the collector followed a linear relationship versus the collector surface and presented a correlation coefficient (R²)of 0,9998. It is important to operate at higher light intensity and large surface in order to reach the meaningful efficiency of the apparatus.