No abstract

No abstract

Heating a solar cell subjected to incident solar irradiance is studied. Laplace Integral Transform technique is applied to get the temperature field within the cell. The efficiency as a function of the cell temperature is estimated, and its variation with the local day time is thus clarified. Different cooling levels are considered. An illustrative example is given. The results show that the diurnal temperature variation of the cell is significant, while the efficiency is revealed to be a slowly varying function of temperature along the day time. It is revealed that as the temperature of the cell increases the efficiency decreases. Thus shading and cooling conditions may be useful to increase its efficiency.

The prediction of the global solar radiation through a distribution function q(t), W/m2 for clear days is given where “t” is the local day time.: The distribution is based on a simple model and is expressed through well-established parameters such as the length of the solar day “td” and the maximum value of the received solar irradiance qmax, w/m2 at time instant “to”.qmax is expressed in terms of the solar constant. Comparison between the computed values of q(t) and the corresponding published experimental data for Hong Kong (China), Valencia( Spain) and Makah (Saudi Arabia) are given as illustrative examples. A test for the degree of fitting is also clarified.