Commercial optical fiber sensors rapidly degrade in performance at distances exceeding 70-100 km. As a result of this, today’s distributed sensor solutions are inadequate for monitoring the well-being of the high-power voltage cables transporting energy from offshore wind farms, and power hubs, to the mainland. In GO-SENS, we address this challenge by developing new long-reach distributed optical sensor systems that rely on carefully designed optical amplifications techniques that are well known from the optical-communication industry.