Thermoelectric Energy harvesting with dual Phase Change Materials as thermal buffers

Inhalt:
The contribution presents the study of using two Phase Change Materials (PCMs) of different melting temperatures as thermal buffers on either side of a thermoelectric generator (TEGs). The high latent heat of PCMs enables them to undergo an isothermal phase change while absorbing or releasing large amounts of heat. This feature of PCMs can be used to scavenge energy from the thermal fluctuations around the environment and to provide a temperature gradient along the TEG twice per thermal cycle. To demonstrate this, two commercially available PCMs, PCM 42 and PCM 24 with melting temperatures of 42 °C and 24 °C respectively, were used on either side of a TEG module and temperatures of these sides were monitored over time. The experimental results show a proof-of-concept of the dual PCM-TEG system by obtaining a reliable temperature gradient twice per thermal cycle.