Thermophotovoltaic efficiency of 40%

Article

关键词: HIGH-TEMPERATURE;    ENERGY-CONVERSION;    STORAGE;    POWER;   

DOI  :  10.1038/s41586-022-04473-y

来源: SCIE

【 摘 要 】

Thermophotovoltaics (TPVs) convert predominantly infrared wavelength light to electricity via the photovoltaic effect, and can enable approaches to energy storage(1,2) and conversion(3-9) that use higher temperature heat sources than the turbines that are ubiquitous in electricity production today. Since the first demonstration of 29% efficient TPVs (Fig. 1a) using an integrated back surface reflector and a tungsten emitter at 2,000 degrees C (ref.(10)), TPV fabrication and performance have improved(11,12). However, despite predictions that TPV efficiencies can exceed 50% (refs.(11,13,14)), the demonstrated efficiencies are still only as high as 32%, albeit at much lower temperatures below 1,300 degrees C (refs.(13-15)). Here we report the fabrication and measurement of TPV cells with efficiencies of more than 40% and experimentally demonstrate the efficiency of high-bandgap tandem TPV cells. The TPV cells are two-junction devices comprising III-V materials with bandgaps between 1.0 and 1.4 eV that are optimized for emitter temperatures of 1,900-2,400 degrees C. The cells exploit the concept of band-edge spectral filtering to obtain high efficiency, using highly reflective back surface reflectors to reject unusable sub-bandgap radiation back to the emitter. A 1.4/1.2 eV device reached a maximum efficiency of (41.1 +/- 1)% operating at a power density of 2.39 W cm(-2) and an emitter temperature of 2,400 degrees C. A 1.2/1.0 eV device reached a maximum efficiency of (39.3 +/- 1)% operating at a power density of 1.8 W cm(-2) and an emitter temperature of 2,127 degrees C. These cells can be integrated into a TPV system for thermal energy grid storage to enable dispatchable renewable energy. This creates a pathway for thermal energy grid storage to reach sufficiently high efficiency and sufficiently low cost to enable decarbonization of the electricity grid.

【 授权许可】

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