Experimental Investigation of Fresnel Lens Application in a Solar Water Heater with the Electricity Generation via Thermoelectric Module

The aim of this paper is to investigate cogeneration of electricity and hot water. In the presented design, thermoelectric module has been devised in the path of heat transfer from solar heat absorber surface to a water reserve. Besides, Fresnel lens is employed to concentrate sunlight as well as to reach justified temperature by the means of thermoelectric modules. The Fresnel lens belongs to a class of point focus lenses, which its dimension is 30*30 cm2. In order to optimal use of the thermoelectric capacity, it is proposed to devise an array of Fresnel lenses which can transfer heat to the thermoelectric module via mineral oil. The results show that approximately 186W thermal power and 6W electric power can be obtained by use of a thermoelectric module (type TEP1-12656-0.6) and 6 Fresnel lenses. Results indicate that the maximum thermoelectric power generation is 1.08W under radiation intensity of 705.98 W/m2. Moreover, thermal efficiency of system is about 51.85%.