Professional Answer: The primary difference is that OPGW is a dual-purpose cable, combining the function of a traditional ground wire with an integrated optical fiber communication channel. While a traditional ground wire only provides lightning protection and a path for fault currents, OPGW offers these same critical safety functions while also enabling high-speed, reliable data transmission. This allows utility companies to establish communication networks for real-time monitoring and control of the power grid, optimizing performance and enhancing reliability.