The performance of flat-plate collectors depends on the heat loss by convection. The performance can be improved by incorporating double glazing, but this decreases the solar radiation reaching the absorber plate due to double reflection. Therefore, the use of single glazing gives better efficiency compared with the double. A large array of flat-plate collectors (FPC) can be formed in the following ways: 1. (i) Parallel connection: A parallel connection is made by connecting the upper and lower. Solar radiation varies with (i) inclination of the surface for a given latitude, (ii) orientation, (iii) time of the day, and (iv) day of the year. Hence, there should be an optimum. Dust deposited on the top transparent cover decreases the transmittance of incident solar radiation, which eventually increases scattering losses. It critically affects the. The conventional flat-plate collector requires an external source of electrical energy for forced-mode operation. This requirement of electrical energy can be fulfilled.