Author: Mike Hines, NED for US Strategic Growth
Beneath the rolling swells of our oceans, a silent revolution is powering the modern world. Thousands of miles of undersea power cables—including export and array cables for offshore wind, international interconnectors, and inter-island links—form a vital bedrock of the global energy transition.
These cables are the unsung heroes of the modern electricity grid. They do more than just transmit power; they increasingly play a role in global communications, housing the fiber optics that stitch our digital world together. Yet, because they are designed to be unseen and are assumed to remain static once installed, they often fall victim to a “fit and forget” mentality. In an era of escalating energy demands and heightening security concerns, treating these critical assets as “out of mind” is a risk the industry can no longer afford to take.
Quantifying Cable Health with Indeximation®
Historically, the industry has relied on periodic physical undersea surveys—costly, intermittent snapshots that often miss the gradual onset of cable fatigue or external damage. Distributed Acoustic Sensing (DAS) offers a route towards continuous monitoring but its large data volumes have meant it is typically only used to understand current conditions, which again misses the gradual onset of risks. Indeximate is fundamentally changing this paradigm through our core technological breakthrough: Indeximation®. Indeximation® is the primary advancement that enables us to compress, upload, store, and analyze that data in the cloud, transforming the existing fiber optics within power cables into a persistent, non-invasive sensing network from which long-term trends can be extracted.
This enables a shift from reactive repairs to predictive maintenance by quantifying the health of assets through seven key measurands:
- Abrasion: Detects wear caused by contact with the seabed or debris, identifying threats to the cable jacket long before they escalate into costly cable failures.
- Armor Integrity Risk: Provides a continuous health check on the cable’s external protective shielding, flagging structural compromises that lead to corrosion and core damage.
- Depth of Burial/Cable Exposure: Pinpoints unburied or “free-spanning” sections with surgical accuracy, allowing operators to remediate assets before they are snagged by anchors or impacted by currents.
- Fatigue: Transforms acoustic signatures into a predictive timeline of material degradation, enabling data-driven life-extension strategies instead of conservative, scheduled replacements.
- Cable Skipping/Pinning: Tracks hazardous lateral movement or improper “pinning” on the seafloor, ensuring that assets intended to remain static are not suffering from mechanical instability.
- Summed Strain: Quantifies cumulative physical tension at roughly 33-foot (10-meter) intervals along the entire cable length, ensuring the asset stays within its safe mechanical design limits.
- Tidal Vibration: Isolates destructive resonant frequencies and vortex-induced vibrations caused by aggressive tidal flows, protecting cables from the silent mechanical stressors of the ocean.
We present these trends in the Scattersphere®, a simple and easy to understand map-based interface that allows asset owners to continuously assess the risks faced by their cables. By using the Scattersphere, cable owners can access up-to-date information about risks faced by their cables in an easily digestible format.
By pinpointing locations of concern with surgical precision, Indeximate provides the guidance needed for targeted, improved physical surveys and helps avert catastrophic failures.
Real-Time Structural Health Monitoring
The value of this data-driven approach extends beyond the cables themselves to the very foundations of our energy infrastructure. Modern offshore wind turbines, often standing over 500 feet (152.4 meters) above the ocean surface, serve as ideal subjects for advanced sensing – using the array cables coupled to the foundations beneath the waves.
Through the Scattersphere®, operators gain access to rich metocean data, including wave height analysis, the direct impact of waves on tower structures and, both blade and turbine performance effects. This Structural Health Monitoring (SHM) offers a holistic view of the wind farm’s physical state. By understanding how environmental stressors affect towers and foundations in real-time, operations and maintenance (O&M) teams can extend the life of aging assets and de-risk the expansion of offshore infrastructure.
Enhanced Maritime Domain Awareness and National Defense
As subsea infrastructure grows in strategic importance, it becomes an increasingly sensitive target for both accidental and intentional interference. Offshore wind farms are now viewed as quintessential “dual-use” technologies, serving as both power plants and all-encompassing sentinel platforms for national security.
Indeximate is pioneering a new frontier in Maritime Domain Awareness (MDA). While radars can be advantageously affixed on the tall towers to surveil airspace far out to sea, by utilizing the high-fidelity acoustic sensitivity of Distributed Acoustic Sensing, the Scattersphere® transforms existing cables into “underwater hydrophone arrays”. This system detects vessels on or below the surface, creating greater than 1.3-mile (2 km) corridors of awareness associated directly with critically important subsea infrastructure.
Crucially, this detection works in all weather conditions and functions independently of the operational status of the vessel’s Automatic Identification System (AIS). This provides an unprecedented layer of situational awareness, turning subsea power cables into a defensive perimeter that adds a key element of consciousness for the national grid.
Whether you are interested in suspicious loitering activity near cables, conducting surveys of vessel tracks around the cables, or just wanting to better monitor the activity and safety of your own vessels on site, the Scattersphere can help.
The Path Forward
We cannot manage what we do not measure. By bringing “out of sight” assets into clear, data-driven view, Indeximate provides the tools necessary to ensure the performance, longevity and resilience of offshore energy infrastructure.
