Solar thermophotovoltaic using Al/sub 2/O/sub 3//Er/sub 3/Al/sub 5/O/sub 12/ eutectic composite selective emitter

Thermal emission properties of Al/sub 2/O/sub 3//Er/sub 3/Al/sub 5/O/sub 12/ eutectic composite are studied for the application of selective emitter of thermophotovoltaic (TPV) power generator. Since this material has a unique structure, high mechanical performance would be expected. Selective emission bands at wavelength 1.5 /spl mu/m due to Er/sup 3+/ ions are observed. Since these emission bands match up the sensitive region of GaSb PV cell, Al/sub 2/O/sub 3//Er/sub 3/Al/sub 5/O/sub 12/ eutectic composite is a suitable emitter material for TPV systems. Solar TPV system with a dish-type solar concentrator (diameter=1.56 m) has been made and tested using the selective emitter material. The performance and component temperature are studied for the system equipped with broad band SiC and Al/sub 2/O/sub 3//Er/sub 3/Al/sub 5/O/sub 12/ eutectic composite selective emitters. Low thermal load for TPV optical components is confirmed for the selective emitter system. The improvement of fill factor of GaSb PV cells is also observed for selective emitter system.