Energy harvesting device and energy harvesting system
An energy harvesting device configured to convert thermal energy into electrical energy includes a heat storage portion configured to store thermal energy, a thermoelectric element configured to eliminate a temperature difference between electrodes when converting thermal energy into electrical energy, and an insulating portion in contact with the heat storage portion and the thermoelectric element. The heat storage portion has insulating properties. The thermoelectric element includes a pair of electrodes having work functions different from each other, and an intermediate portion provided between the pair of electrodes. The thermoelectric element is provided in contact with the heat storage portion and is covered by the insulating portion.
1 . An energy harvesting device configured to convert thermal energy into electrical energy, comprising:
a heat storage portion having an insulating property and configured to store thermal energy;
a thermoelectric element:
disposed on the heat storage portion in an upward direction of the energy harvesting device,
including:
a first electrode;
a second electrode, having a work function different from a work function of the first electrode, disposed above the first electrode in the upward direction; and
an intermediate portion disposed between the first electrode and the second electrode, and
configured to eliminate a temperature difference between the first electrode and the second electrode when converting thermal energy into electrical energy; and
an insulating portion disposed on the heat storage portion in the upward direction and covering the thermoelectric element to contact an upper surface of the thermoelectric element and side walls of the thermoelectric element, wherein
the intermediate portion includes a solid insulating layer in which nanoparticles are fixed in a dispersed state.
2 . The energy harvesting device according to claim 1 , further comprising:
a heat conduction portion disposed on the heat storage portion in the upward direction and between one of the side walls and the insulating portion in a direction perpendicular to the upward direction to contact the one of the side walls and the insulating portion.
3 . The energy harvesting device according to claim 1 , wherein the heat storage portion includes a sensible heat storage material.
4 . The energy harvesting device according to claim 3 , wherein the heat storage portion includes an aerogel.
5 . The energy harvesting device according to claim 1 , wherein a specific heat of the heat storage portion is larger than a specific heat of the insulating portion.
6 . The energy harvesting device according to claim 1 , further comprising:
a solar cell panel configured to convert light energy into electrical energy, wherein the thermoelectric element is sandwiched between a back surface of the solar cell panel and the heat storage portion.
7 . The energy harvesting device according to claim 6 , further comprising:
a heat conduction portion provided in contact with the solar cell panel, the heat storage portion, and the thermoelectric element.
8 . An energy harvesting system comprising:
the energy harvesting device according to claim 1 ;
a solar cell panel configured to convert light energy into electrical energy; and
a power generation amount measurement unit configured to measure power generation amounts of the thermoelectric element and the solar cell panel.
9 . The energy harvesting system according to claim 8 , further comprising:
a power measurement unit configured to measure power of the thermoelectric element, and
an estimation unit configured to estimate power generated from the solar cell panel based on a measurement result of the power measurement unit.