Workshop: Durability of Cables and Moorings in Tidal Flows – PRESENTATIONS






On March 31, 2016, FORCE (Fundy Ocean Research Centre for Energy), along with Marine Renewables Canada and the Offshore Energy Research Association (OERA) co-hosted a workshop on the topic of Durability of Cables and Moorings in Tidal Flows.

The objective of the workshop was to bring together experts and stakeholders to discuss an applied research program that would focus on the durability of marine infrastructure, particularly cables and mooring systems in high-energy tidal flows. It is critical to identify and address these new challenges to infrastructure durability if the in-stream turbine industry is to become viable.  This workshop will initiate R&D in this area within the Bay of Fundy and abroad.

Workshop Proceedings

The workshop brought together over 65 participants representative of the supply chain, tidal energy project developers, government, academia and NGOs. Over the course of the event, local and international industry experts provided information on previous experiences/issues with cables/moorings (in the MRE industry and others such as Oil & Gas) as well as information on current research being done on the topic.  Below is the workshop agenda, presentations and proceeding for your review:


• Presentations:

Workshop Notes / Question & Answer


Below are the original details of the workshop:

Workshop Details:
Date: March 31, 2016
Time: 9:00 am- 4:45 pm
Location:  The Art Gallery of Nova Scotia ~ The Lecture Theatre Room
– 1723 Hollis St, Halifax, NS

RSVP: Email Amanda White at no later than March 25th, 2016
**Space is limited – will work on RSVP first come, first serve basis

Workshop Format:
– Presentations by experts in the field, including industry leaders and practitioners from the local and regional tidal community as well as international experts
– Roundtable discussion between presenters and attendees

Workshop Target Outcomes:
– Identification of the relevant issues, with a corresponding plan that outlines a strategic approach to addressing these issues
– Initiate R&D in this area within the Bay of Fundy and abroad

As a new industry, in-stream tidal power generation cannot become economically viable without significant research advances.  Two of the least studied yet most critical material components of this industry are power cables and mooring systems.  In the Minas Passage, Bay of Fundy, four power cables, owned in part by the Province of Nova Scotia, have been successfully laid, and several more are needed to accommodate the planned extraction of hundreds of megawatts of power.  Mooring systems are the foundation for both marine operations (and hence marine safety) and marine infrastructure.

Outside of the tidal industry, there has been an enormous amount of research conducted on the durability of submarine cables and mooring systems, but in relatively quiescent marine environments.  However, as attested to by two experts in the field, many of these standards simply do not apply in high-energy tidal flows:

Simon Melrose (Fundy Ocean Research Center for Energy) on mooring systems in tidal flows:  “Since 2007, we have been involved in the installation of moorings in Minas Passage, primarily for oceanographic data collection.  We have been following the tried and true technologies and work practices developed over many years in almost every marine environment from the high Arctic to the Equator…It is becoming apparent that these practices and general rules are not always enough when working in high current flow regimes… We are routinely seeing equipment such as galvanized shackles that have been dramatically corroded and worn in weeks rather than the months or even years we would expect based upon working elsewhere.”

Mike Nichols (ETA Ltd.) on cables in tidal flows: “Few cables are deliberately installed in high current regimes for obvious reasons. Where in the past they have been (electricity supplies to the remote Scottish Orkney islands for instance) their life has sometimes been very short. The mode of failure that I have personally observed is the armour wires being worn away and eventually breaking.  The break area is characterised by the armours being formed into very sharp points. The armours are always shiny bright…A recent unrelated discussion on observing the same phenomenon in telecom cables (similar to the FORCE data cable) has suggested that this type of failure may actually be due to electrolytic action rather than wear.”