Regenerative Thermophotovoltaics

Background: Thermophotovoltaics (TPVs) converts infrared rays from a very hot thermal source into photovoltaic electricity. This process is analogous to using solar cells but TPVs use thermal emitter and a photovoltaic diode cell to change energy forms. Conventional silicon solar cell is effectively a TPV device in which the sun functions as the emitter and the cell’s silicon structures absorb in the visible portion of the spectrum. Many solar cell systems neglect the small infrared photon emissions due to known physical and design constraints. Thermophotovoltaic devices are uniquely positioned to overcome that limitation by harvesting the unconverted thermal-infrared emissions. Historically the efficiency for such devices (with spectral selectivity) reach only 15%. For a world with increasing energy and conservation needs a thermophotovoltaic module solution would need to perform at higher efficiencies for a variety of high- and low-power demand scenarios. Technology Description: To address these problems researchers at the University of California Berkeley have developed the \"Regenerative Thermophotovoltaics\"" framework which is designed to exploit the small infrared photons typically lost in thermophotovoltaic cells while architecting the device for optimal variable-demand performance. The Berkeley device framework effectively captures and recycles unused photons in the photovoltaic cell that are generally below ~0.8eV energy. By putting these thermal-infrared photons to work conversion efficiencies >50% may be produced which could contend with conventional internal combustion engine (ICE) approaches. Applications: 1) Automotive power systems 2) Trucking power systems 3) Stationary power systems"