In this study, mathematical model simulation is done for using thermoelectric module (TEM) as thermoelectric generator (TEG) by Matlab/Simulink simulation program; and mathematical model and simulation results for different temperature ranges are confirmed by experiments. Current, voltage, power, hot side and cold side heats and temperature difference between the surfaces of module values for continuous monitoring and registration of a special SCADA program is developed. When Matlab/Simulink simulation results obtained from the theoretical are compared with the experimental results measured by the SCADA, the results are as follows; system average error percentages; 5.57% for current, 5.12% for voltage and 3.72% for power. TEG output voltage Vmax = 2.2V, output power Pmax =6.71W and efficiency 3.4% are obtained, when amount of waste heat sink into TEG is QH =197W and the matched load resistance is matched to the internal resistance at the 100°C temperature difference. The results of experimental and theoretical analysis show that TEG has a promising potential at the recovery of waste heat for low temperatures in especially industrial and geothermal areas.