Performance Improvements in Flexible Photovoltaic Technologies for Military Technology

Thin film amorphous silicon photovoltaic, PV, modules can provide an efficient, light weight and conformal renewable energy source to supplement/replace existing electrical generators. The fuel delivery for these generators, particularly to forward operating bases, can be quite costly and can put men and equipment at risk of attack. Additionally, portable solar can be advantageous for civilian emergency response teams involved with natural disaster recovery actions where resources have become scarce. Research and development opportunities to improve performance of the amorphous silicon solar material include improvements to the recombination/tunnel junction, the P+ layer deposition, and to the light collection efficiencies. The tandem PV device relies on the junction between the interface between the bottom and top layers of the tandem PV material to pass electrical current. Because of this being a reverse biased diode, a tunnel junction is created to allow for current to pass through. This junction has a voltage loss associated with it which can be improved upon thereby increase the over all device performance. The rate at which PV material can be processed through the silicon machine is limited by the rate at which a suitable P+ layer can be deposited. Improved deposition rate of this P+ layer will allow for the improved production of PV at a reduced cost. Improved light collection efficiencies would increase the power output of the PV device thereby reducing size, weight and complexity of installed power. The original document contains color images.