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Efficiency, Fill Factor and Active Solar Cell Area

For the solar cell interconnection and encapsulation of the high performance solar arrays of the 'Spirits' the most advanced techologies were used. The fill factor with solar cells for the 8 m² solar array was beyond the values achieved up to then. In 1990, a fill factor of 97 % was achieved with single shingle arrangement for the Spirit of Biel II solar array. Next in 1993, the fill factor was increased to a fantastic value of 99 % with a two-dimensional shingle arrangement for the Spirit of Biel III solar array.

This value is also a criterion for the active solar cell area. For the first time, the efficiency of a complete interconnected, wired and encapsulated solar array was better than that of a single solar cell! Already in 1993, a 19 % efficiency solar arrays was manufactured out of 18.4 % efficiency solar cells with our two-dimensional shingling technology.

Even more advantages came along with this new technology: decreased contact resistance, better redundancies, avoidance of match losses and hot spot effects. We used this same technology for the world record module, topped with a non reflective module surface.