The offshore wind subsea power cable repair market has been gaining significant attention in recent years. Although typically representing less than 10% of the overall capital spend for an offshore wind farm, subsea power cables are critical as without these the wind turbines are unable to deliver their power. There has been an unfortunate trend in power cable failures, with one widely quoted source stating more than 40% of offshore wind construction period claims are related to cables, accounting for more than 350 million Euro in claims since 2010 averaging at around 100 days outage. The outages are for a variety of reasons including installation and manufacturing problems as well as damages by third parties such as fishermen or anchor-drops.
Although cables, cable protection measures and cable installation ships have seen steady technological evolution and change, the method for repairing broken or damaged subsea power cables has largely remained unchanged for nearly a century except for iterative adaptations. Timescales for cable repairs vary anywhere from weeks to months depending on availability of key personnel, specialist ships, spares and equipment; and the ships have to travel to site, cut the cable in-situ to lift to the deck for repairs. A lot of the excessive timescales are driven by the necessity to lift a damaged cable to deck and is a combination of weather impacts as well as the repair activities themselves. Now there are alternative means to address this challenge through the recent introduction of practical, industry-led commercial in-situ subsea power cable repair solutions paired with subsea cable jointers. This promises to cut the cost of an average subsea cable repair in half and increase competition in the subsea power cable repair market segment, by opening up the possibility of undertaking repairs from a greater range of vessels, reducing reliance on a small number of specialist cable repair vessels. An in-situ subsea power cable repair can demystify and simply what is an extremely complex marine logistics challenge, while improving the resilience and integrity of the cable post-repair, potentially offering the possibility for fixed price subsea cable repairs.
The presentation intends to provide a snapshot of the current status quo of subsea power cable repair methods and consider the in-situ solution, its challenges and opportunities.
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By Alex Gauntt – Commercial Director of Irish Sea Contractors
Alex will be talking about current common subsea power cable repair methods
and enabling in-situ subsea power cable repairs at the 5th Annual Offshore Power Cable Engineering and Reliability Forum on 27-28 March 2018 in Berlin. Don’t miss the event to learn more!