Transmissive Concentrator Multijunction Solar Cells With Over 47% In-Band Power Conversion Efficiency

Transmissive concentrator multijunction (TCMJ) solar cells with over 47% in-band power conversion efficiency (PCE) have been designed and realized. These TCMJ solar cells have been characterized under 1 sun and concentrated 500 sun solar spectra, showing that the PCE for in-band light (photon energies above the cell's lowest bandgap) can reach up to 47.6% (29.5% for the full solar spectrum). Temperature coefficients of electrical parameters (V-oc, J(sc), fill factor) have been derived from measurements within the temperature range of 20 degrees C-130 degrees C, showing linear variations versus temperature change. Optical measurements demonstrate that the cells show 76.5% solar-weighted optical transmission for the out-of-band light (photon energy below the cell's lowest bandgap). This TCMJ solar cell exhibits promising spectrum splitting capability, which has the potential for use in hybrid photovoltaic-solar thermal applications. Published by AIP Publishing.