Rollable solar plant

Rollable solar plant

Source:

https://www.osti.gov/

https://www.sciencedirect.com/

https://ieeexplore.ieee.org/

A solar generator panel for satellite and terrestrial energy supply systems comprises flexible support having a plurality of solar cells mounted on the support and being rollable and foldable therewith. Connector means are provided for electrically interconnecting the cells in either parallel or series. At least one conducting layer is applied to the opposite side of the support from the solar cells and is adapted to be grounded to the associated satellite or to the earth for the purpose of eliminating charged carriers. The back of the assembly is advantageously provided with a layer of adhesive mixed with electrically conducting particles and particularly silver powder particles which serve to connect the solar cells through to the satellite. The proportion of the electrically conductive particles in the adhesive layer is preferably about 50%.

Compared to standard solar arrays carrying rigid cells, flexible arrays allow novel deployment mechanisms. In order to take advantage of reduced stowed volumes, novel array concepts must be available, before lightweight, flexible thin-film cells can play off their benefits and yield a significant advantage with respect to existing space power technologies. Even very advanced new thin-film cells or sub-modules alone cannot achieve real breakthroughs without adapted array and deployment techniques.

Hence, flexible thin-film cells development efforts must be synchronized with development steps for novel solar generator concepts. Amorphous silicon solar cells have been successfully fabricated on ultra-thin SS substrates with down to 7.5 pm in thickness. Using a carrier method throughout the fabrication process, we obtained ultralightweight solar cells that have similar performance as solar cells on regular 127 pm substrates. The
solar cell efficiency could be further improved when a back-reflector is used and when a triple-junction solar cell
is fabricated on these substrates.

The solar cell yield, although slightly lower than those on thicker SS substrates, is however very promising. These 6.5% efficient solar cells deposited on 7.5pm thick SS substrates exhibit a specific power of 1.08 kW/kg, significant for space power application. We have studied the use of various types of SS substrates. The results we obtained so far appear to suggest that the as-rolled AIS1316 SS foil is most suitable for the fabrication of a-Si based solar cells for space application.