Silicon-based solar cells Characteristics and production processes ...

Silicon-based solar cells – characteristics and production processes
The photovoltaic industry is a very modern and mostly automatized production
sector, which applies advanced technologies and technical solutions. The efficiency
of the production lines of a typical facility manufacturing 6-inch solar cells on the
basis of crystalline silicon amounts to about 1500 items of solar cells per hour, which
gives the annual production at the level of 50 MW p . Solar cells are currently
manufactured with the application of various methods and technological processes
and with the use of numerous base materials, which are the most important
discriminants of the five basic classification groups of the cells, presented in Fig. 2.
Due to the existing number of types and diversified constructions of the cells, a lot of
the latter’s properties qualify them simultaneously to a few groups. Table 1 contains
only a basic division of solar cells together with a specification of the cell types which
are the most frequent representatives of the given group. The table also includes the
values of photovoltaic conversion efficiency (E ff ), that is the ratio of the power
obtained from the cell to the illumination power, for the best cells produced under
laboratory conditions and for the typical photovoltaic modules, available as
commercial market products. Table 1 does not include the efficiency of highperformance
modules.
Tab. 1. Basic solar cell types classified according to groups and the highest photovoltaic
conversion efficiencies for a given cell (E ff of the cell), module (E ff of the module), and the
module producers of a given cell type [1], [2].
Cell group Cell type E ff of cell
[%]
Crystalline Si
Highperformance
E ff of
module
[%]
Module producer
Mono-crystalline 24,7 22,7 SunPower – USA [3]
(Cz-Si)
Poly-crystalline 20,3 18,6 Mitsubishi – Japan [4]
(mc-Si)
Micro-crystalline 11,7 10,9 Sanyo - Japan [1]
(μc-Si)
Ribbon (R-Si) - 13,4 Evergreen - USA [5]
HIT 21,8 17,3 Sanyo – Japan [2]
GaAs 25,8 - -
InP 21,9 - -
GaInP 2 /GaAs 39,3 - -
Thin-layer CdTe 16,5 10,1 First Solar – USA [2]
CIGS 19,5 12,2 Solibro - Germany [1]
Amorphous Si (a-Si) 10,1 7,5 NES - China [6]
Organic Polymer 5,1 1,8 Konarka - USA [6]
Photochemical Dye – Grätzel 11,4 11,1 Sharp - Japan [3]
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