In this study, mathematical model simulation was 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 were 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 was developed. When Matlab/Simulink simulation results obtained from the theoretical were compared with the experimental results measured by the SCADA, the results were as follows; system average error percentages; for current, voltage and power: 5.57%, 5.12%, 3.72% respectively. TEG output voltage Vmax = 2.2V, output power Pmax = 6.71W and efficiency 3.4% were obtained, when amount of waste heat sink into TEG was QH = 197W and the matched load resistance was matched to the internal resistance at the 100 degrees 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.