Hybrid Energy Harvesting Systems

ABSTRACT: Efficiency of solar cells is typically low reaching on the order of 10% for commercially available cells. Furthermore, efficiency decreases by 0.5% for every degree increase in operating temperature. In order to increase the efficiency of the conversion of solar radiation per unit area to electricity it becomes advantageous to combine the solar cell with a thermal energy harvester. Acting as a thermal backplane, the thermal energy harvester increases the efficiency of the solar cell itself by keeping the solar cell from overheating, as well as allows for the harvesting of additional energy in the form of the suns"heat [2]. For this approach to be successful a thermal energy harvester possessing a high efficiency, high power density and that can be manufactured in a compact thin module is necessary. The magneto-thermoelectric generator developed by researchers at UCLA has the potential to possess such properties. As such, Maritime Applied Physics Corporation (MAPC) in collaboration with University of California Los Angeles (UCLA) proposes to combine the magneto-thermoelectric generator with solar cells to create an efficient and power dense hybrid solar energy harvester. BENEFIT: MAPC foresees numerous applications for the proposed technology. Applications are available for both the stand alone thermal energy harvesting (i.e. with the magneto-thermoelectric energy harvester) where solar energy is not available as well as the proposed hybrid energy harvester where solar energy is readily available. Potential markets for our technology exist in industries employing a broad range of portable and remote low power electronic devices would benefit from a high power density thermal energy harvester. Low power electronic devices primarily exist in wireless sensor networks (WSNs) used for applications such as condition monitoring, and in radio frequency identification (RFID) tags used, among other things, for inventory tracking. Wireless sensor networks (WSNs), could be expanded with additional nodes, functionality and accelerated rate of data transmission utilizing our proposed technology. Sensor networks and clusters, found today in health monitoring of oil refineries, power plants, civilian structures (e.g., bridges), aircraft, automobiles, ships and trains, could be powered via harvested waste heat, with an attendant reduction in the use of batteries.