Ultra‐efficient intrinsic‐vertical‐tunnel‐junction structures for next‐generation concentrator solar cells

• Published in: Progress in photovoltaics 2021-02, Vol.29 (2), p.231-237
• Main Authors: Seoane, Natalia, Fernández, Eduardo F., Almonacid, Florencia, García‐Loureiro, Antonio
• Format: Article
• Language: English
• Subjects: concentrator photovoltaics; Concentrators; Energy gap; intrinsic semiconductors; Luminous intensity; microscaling; Photovoltaic cells; Solar cells; ultrahigh light intensities; vertical solar cells
• ISSN: 1062-7995; 1099-159X
• DOI: 10.1002/pip.3369

The efficiency of solar cells can be enhanced by increasing the light intensity and/or the number of bandgaps of the structure. However, current solar cells cannot fully exploit these two factors because of various critical drawbacks. Here, we show a novel microscale, that is, side ≈ 0.5 mm, vertical solar cell structure that does not suffer the series resistance and bandgap limitations issues of current devices. The preliminary structures investigated show extreme efficiencies, >40%, at ultrahigh concentration factors of 15 000 suns. In addition, future designs with a better bandgap configuration are expected to deliver cells with efficiencies far above 50% at extreme light intensities. This early design offers a fast and reliable route to push the efficiency towards the maximum solar conversion limit and represents a promising way to develop new‐generation ultraefficient and low‐cost concentrator photovoltaic systems. We propose a novel type of solar structure that does not suffer the resistance and bandgap optimisation limitations of current concentrator solar cells. The new cell offers a unique route to achieve efficiencies far above the state of the art, >60%, and represents a promising way to push the efficiency towards the maximum conversion limit.