Impact-9 Open Seas (FS045)

Project Outcome:

Impact-9 “Open Seas” studies a fish-pen called Net9, based on novel flexible materials for high energy marine sites. Benefits include:

1. Storm survival.
2. Safer operations.
3. Fish health and selective submergence of stock.

In this study Tension Technology International assess the technical feasibility of the solution and undertake further engineering of novel aspects, applying experience from their “NetBuoy” technology, which uses impermeable membranes and rope-encapsulation to manufacture buoyant modules. This approach significantly reduces structural mass compared to steel and is compliant to waves.

The techno-economic potential of Net9 is addressed in detail with reference to specific UK regions. Consideration of offshore aquaculture integrated with planned offshore wind leased zones shows potential to greatly improve the economic return of those leases. The assessment shows that a reasonable long-term target could be to produce 1 million tonnes of salmon in Scottish offshore zones, representing a £5 billion market, 40% of current global salmon production levels. The spatial requirements for this level of production would be very modest by comparison to equivalent offshore wind economic activity, for example.

Furthermore, if offshore production is paired with inshore farms to provide early stage smolts for offshore grow-out, it is economically attractive to convert those inshore farms to closed-containment operations that have a greatly reduced environmental footprint. In that model, significant increases in overall salmon production could be realised, while the overall environmental impacts of the sector reduce from current levels.

Experts from SAMS, EMEC and Maritime Aqua provide a risk review of the proposals.