Protection Of TEG Module at High Temperature Transient Boundary Condition Using Phase Change Materials, an Experimental Investigation

Although every thermoelectric module (TEM) has a certain optimum temperature condition, however keeping the constant temperature boundary conditions is not practical in most applications. When a thermoelectric generator works at lower temperature than its optimum condition, reaching the maximum efficiency is not promising. In addition, working at higher temperature than the optimal operation temperature not only reduces the performance of the system but also it may damage the module. In this study, in order to control the temperature of the hot side of the thermoelectric module, some different phase change materials (PCM) in an aluminium box are placed between heat source and the thermoelectric module. The results show when the input heat flux is high, a fraction of the thermal energy is saved in the PCM during the melting process, and when the heat source is off, the saved energy in the PCM release slowly, causing a more stable electrical energy production by the TEM and lower the effect of the heat source temperature fluctuations. This study also shows by design of a proper geometry and selection of efficient PCMs, not only the high temperature pulse by the heat source is damped, also more stable electricity for longer time is possible when the heat source is off.