Toward ultrahigh-flux photovoltaic concentration

We report experimental results with a miniature fiber-optic photovoltaic concentrator with (a) deliverable power density up to 10(4) suns (10 W/mm(2)), (b) solar cell efficiencies above 30%, (c) completely passive cooling, (d) uniform and individualized cell illumination, and (e) assembly from readily available components. Measurements include the sensitivity of the conversion efficiency of tandem III-V cells to (1) power input, (2) flux distribution, and (3) the modified spectrum from the fiber-optic concentrators. Our results augur favorably for the feasibility of such designs at concentration levels as high as thousands of suns. (C) 2004 American Institute of Physics.