Its genius lies in its dual functionality: it serves as a conventional ground wire (or shield wire) to protect the high-voltage conductors from lightning strikes, while simultaneously housing optical fibers in its core to provide a high-speed data path. Such cable combines the functions of grounding and telecommunications. An OPGW cable contains a tubular structure with. As the grids around us continue to innovate and interconnect, the use of Optical Ground Wire (OPGW) cables now forms the backbone of modern electrical networks. Optical Ground Wire is. OPGW (Optical Ground Wire) is a specialised cable installed at the top of high-voltage overhead transmission lines.