Abstract: A folding photovoltaic strip device is provided comprising a plurality of photovoltaic modules joined to form a strip and pleated by flexible, transverse creases so that the device may be stored folded together along the creases, in a compact form, and the creases sprung opened to expose the modules to energizing light. The creases are permanent to facilitate folding the device for storage, and the ends of the strip may be attached to a casing and a lid in which the strip is to be stored.