Theoretical and experimental study of cascade solar cells

Thesis/Dissertation · Thu Jan 01 04:00:00 EST 1981

OSTI ID:6274945

Chiang, J P.C.

Two-junction cascade solar cells were investigated with an emphasis on the AlGaAs material system. The solar cells have been grown monolithically by the Liquid Phase Epitaxial (LPE) technique. The current-voltage characteristics with and without illumination were examined with a current source, voltage and current meters, and a commercial solar simulator. The material and device parameters affecting the performance of the solar cell were measured. A computer program was used to analyze the experimental data and to compare with the theoretical values. The I to V measurements reveal that the generation - recombination mechanism dominates throughout the voltage region where the solar cells normally operate. The calculated efficiency of the optimized cascade device composed of a top cell of AlGaAs with a bandgap of 2.0 eV and a bottom cell of GaAs is 20% without an antireflection coating. Current mismatch which results in a low short circuit current has been found for most of the cascade cells. The experimental results show an efficiency in the range of 10 to 15% without antireflecting layers. Along with the low short circuit current and the poor fill factor, the low open circuit voltage which is due to the high dark current, causes the discrepancy between the theoretical and experimental values of solar cells in this study.

• OSTI ID: 6274945
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
140501* -- Solar Energy Conversion-- Photovoltaic Conversion
ALUMINIUM ARSENIDES
ALUMINIUM COMPOUNDS
ARSENIC COMPOUNDS
ARSENIDES
CASCADE SOLAR CELLS
COMPUTERIZED SIMULATION
DIRECT ENERGY CONVERTERS
EFFICIENCY
ELECTRICAL PROPERTIES
EPITAXY
EQUIPMENT
FABRICATION
GALLIUM ARSENIDES
GALLIUM COMPOUNDS
LIQUID PHASE EPITAXY
PERFORMANCE TESTING
PHOTOELECTRIC CELLS
PHOTOVOLTAIC CELLS
PHYSICAL PROPERTIES
PNICTIDES
SIMULATION
SOLAR CELLS
SOLAR EQUIPMENT
TESTING