Performance Analysis of Thermoelectric Modules Consisting of Square Truncated Pyramid Elements Under Constant Heat Flux

System design of a thermoelectric (TE) power generation module is pursued in order to improve the TE performance. Square truncated pyramid shaped P–N pairs of TE elements are connected electronically in series in the open space between two flat insulator boards. The performance of the TE module consisting of 2-paired elements is numerically simulated using commercial software and original TE programs. Assuming that the heat radiating into the hot surface is regulated, i.e., the amount of heat from the hot surface to the cold one is steadily constant, as it happens for solar radiation heating, the performance is significantly improved by changing the shape and the alignment pattern of the elements. When the angle θ between the edge and the base is smaller than 72°, and when the cold surface is kept at a constant temperature, two patterns in particular, amongst the 17 studied, show the largest TE power and efficiency. In comparison to other geometries, the smarter square truncated pyramid shape can provide higher performance using a large cold bath and constant heat transfer by heat radiation.