Performance analysis of thermoelectric power-generation system with natural convection cooling

Nowadays, high-performance electronic devices release large amounts of heat throughout their operation. Thermoelectric passive cooling systems can offer a cost-efficient and straightforward solution for the thermal management of such devices based on a passive heatsink and a thermoelectric generator (TEG). TEG can transform a part of the heat generated by the electronic chip into electricity for the power supply of microelectronic systems. The thermoelectric system investigated here contains a 12 W Positive Temperature Coefficient (PTC) heating element placed on a 4 × 4 cm2 aluminium plate, a commercial SP1848-27145 TEG device and a finned plate heatsink recycled from a desktop PC. Two types of tests were performed here. An energy efficiency test was initiated at different load resistance values RL between 1 and 40 Ω by directly connecting TEG output to a direct current (DC) electronic load. The second test was developed for electrical power generation at 3.3 V–5 V by integrating a DC–DC boost converter between the TEG output and the electronic load set at RL of 600–900 Ω. It was registered a maximum energy conversion efficiency of 1.17 % for RL=2Ω, close to the internal resistance value of the TEG module. The second test revealed the generation of output electrical powers with minimum values of 15–17.5 mW at a temperature difference between TEG plates of about 20 K.