Self-shape-transformable 3D tessellated bifacial crystalline Si solar cell module enabling extra energy gain through intervals and an integrated actuator

The previously reported strategies for photovoltaics (PVs) have been one-size-one-fits-all methods under a watt per cost concept, which is changing in favor of a customized-fit strategy under an energy yield per watt concept to generate more energy per installed photovoltaic (PV) device and thereby expand applications of PVs. Bifacial solar cells have attracted attention for possible implementation of this new PV concept. In this study, as a novel approach for bifacial technology in urban environments, we propose an automated solar trackable and self-shape-transformable three-dimensional (3D) tessellated bifacial module that can be used with any curved surface and can change shape according to the angle of incidence (AOI) of light to maximize the power output without external assistance. The proposed self-shape-transformable 3D tessellated bifacial module with 2 mm intervals between the cells and with an installed reflector achieved a 47% enhancement in the power output compared with that of a flat module under 1 sun, 1.5 a.m. conditions. At high AOI values, the power output was greater than that of a flat module, owing to solar illumination AOI sensitive shape changes and the effect of bifacial energy production with a controlled reflector. This indicates that the proposed module has strong potential for use in urban environments.