Electric Field Sensors Hint at Smarter Subsea Cable Watch

An emerging sensor technology may enhance subsea cable monitoring, offering the potential for earlier insights and improved resilience in Europe’s offshore networks

17 Dec 2025

Europe’s subsea cable industry is beginning to explore new ways to monitor critical underwater infrastructure, as operators look for earlier and more reliable insight into cable condition and location.

A recent partnership between Alcatel Submarine Networks and French deep tech company ELWAVE highlights growing interest in electric field sensor technology. The approach detects the natural electric fields produced by live subsea power and communications cables, offering an alternative source of information alongside established inspection methods.

The companies say the sensors are intended to complement, rather than replace, existing practices such as ship-based surveys and visual inspections using remotely operated vehicles. By adding another stream of data, operators could track cable position and operating status more frequently. However, large-scale performance data from operational deployments has yet to be published.

Interest in enhanced monitoring tools is increasing as Europe expands offshore wind farms, cross-border power interconnectors and high-capacity data routes. At the same time, subsea cables remain exposed to risks from fishing gear, anchors and seabed movement. Repairs are often costly and disruptive, making earlier detection of potential problems a priority for network owners.

The technology is designed to be integrated into compact underwater robotic platforms, which could reduce reliance on specialised vessels for certain inspection tasks. Industry analysts say this could lower monitoring costs and make more regular surveys practical, particularly in congested or environmentally sensitive areas. They caution, however, that claims of savings and reliability improvements will depend on results from real-world use.

The partnership reflects a broader shift in how subsea infrastructure is viewed. Cables are increasingly treated as active systems capable of generating continuous operational data, rather than static assets checked only at intervals. Demand for greater resilience and transparency is particularly strong in Europe’s offshore energy and telecommunications markets.

Challenges remain in integrating new data sources with existing monitoring frameworks and operational processes. Even so, as electric field sensing moves from trials toward wider adoption, it points to a gradual move towards more informed and proactive management of subsea cable networks.