The present invention relates generally to roofing products. The present invention relates more particularly to roofing products for use with photovoltaic elements, and to photovoltaic systems that include one or more photovoltaic elements joined to a roofing substrate. In one embodiment, a roofing product includes a flexible roofing substrate having a top surface, the top surface having one or more granule-coated zones thereon capable of acting as a receptor zone or an exposure zone, each zone being adapted to receive one or more photovoltaic elements; and an adhesive suitable for securing photovoltaic elements to one or more of the granule-coated zones, the adhesive capable of forming a bond to the granules and the top surface of the flexible roofing substrate and to the bottom surface of the photovoltaic elements.