Power Generation by Thermoelectric Generator Using Different Amounts of Phase Change Materials

In this study, a thermoelectric generator that embeds different amounts of phase change materials for wasted heat energy harvesting is proposed. Paraffin wax with 0.5 wt % multiwalled carbon nanotubes composited is encapsulated in a cuboid polydimethylsiloxane body, which is used as the phase change material. The fabricated thermoelectric generator can generate electricity uninterruptedly with the stored heat in the phase change material when the heat source stops supplying heat. The temperature can hold for several periods of time (about 60 to 100 s) when the phase change material is adopted in a thermoelectric generator. Moreover, the output voltages are about 0.4 to 0.6 mV higher than those of a thermoelectric generator without phase change material under the same conditions due to the stored heat in the phase change material. Specially, the maximum output voltages increase by 10.2 to 13.7%, and the total electricity increases by 31.6% on average, induced by the effect of different active lengths of p-type thermoelectric couples and different amounts of phase change materials.