Tandem amorphous/microcrystalline silicon thin-film solar modules: Developments of novel technologies

Abstract

Tandem amorphous/microcrystalline silicon thin-film solar modules with large-area panels, high energy yield, low light-induced degradation, and high damp-heat reliability are commercially manufactured. Several novel technologies are researched, developed, and introduced into the production line. These include (1) special passivation to increase the shunt resistance by an order of magnitude and enhance modules' low-light performance; (2) large-area uniformity of transparent-conducting-oxide films and lamination processes to reduce the problem of cells' current and segments’ voltage mismatches; (3) segment laser scribing to enable the modules' output voltage to 70 V and 30 V; (4) novel front reflective layers to enable customized color appearance; and (5) special 4-step laser scribing to produce see-through modules of purple, dark blue, light blue, silver, golden, orange, red wine, and coffee colors. Two new types of modules: low-voltage modules and see-through color modules are successfully developed, manufactured, and installed. The performance ratio of a 900 kWp system of 30 V low-voltage modules has been simulated and projected to be 92.1%, which is 20% more than its crystalline silicon and CdTe counterparts. The see-through color modules have been achieved with the highest module power reaching 105 W and the highest visible-light transmittance near 20%.