A composite solar collection module includes a thin film solar collection cell that is encapsulated between a transparent substrate, such as glass, on one side, and an electrically insulating film on the other. A metallic layer is disposed over the electrically insulating film to provide protection against diffusion of atmospheric species that may harm the thin film solar collection cell. The insulating and metallic layers are dimensioned so that a larger collection cell can be used to collect solar energy over a larger proportion of the available substrate surface area, without causing arcing between the cell edge and the metallic layer edge.