1. IMPROVED SEABED ANCHORING TECHNOLOGY Innovation Opportunity Identified at PROTTEC Retreat 26/28 October 2010 Jonathan Williams, Marine South East

2. Basic Ideas Permanent seabed anchors are expensive, eg for: –Offshore platforms –Renewable energy arrays Conventional installation is based on techniques developed on land –Piling/drilling –Require expensive vessels Can we envisage a novel approach, particularly for renewable energy arrays? –Using subsea tooling, based on experience with similar seabed vehicles (at SuperCAT)? MSE has performed further analysis to explore this possibility

3. Current Practice - Shallow Piled from jack-up barge: –Expensive (>€100k/day) –Depth limited (~35m) –Subject to weather & scheduling delays Gravity base: –Mainly for moored devices –Limited load capacity –No ‘pull-out’ capacity

4. Current Practice - Deep Torpedo pile: –Developed to moor FPSOs –Avoids use of expensive rig –Depends on seabed type & sufficient water depth Drill & grout –Requires very expensive drill ship Gravity base: –As for shallow water

5. Concept Remote tooling to deploy on seabed Explosive anchors pinning an anchor plate? –Marinise techniques used successfully on land Horizontal & vertical load capacity –Increased mooring flexibility

6. Market Analysis Offshore wind (deeper water >35m) –Floating turbines (eg Hywind) with mooring –Tripod/quadripod –€0.5M per installed MW (Gifford) for 15GW equals €7.5B market (but cost reduction will be essential!) Wave & tidal (floating devices) –Mooring systems need lots of anchors Eg Pelamis = 1 anchor per 250kW –Moored devices for 40% of EU target (5GW by 2020) equals 8,000 anchors –€125k per anchor (estimate) equals €1B market 35-50m water depth is priority for continental shelf renewable energy arrays

7. Potential Concerns Environmental noise impacts –Need risk assessment –Faster installation = less duration of impact –Easier limiting to less sensitive seasons

8. Science & Engineering Status Foundations & moorings identified as priority by Energy Research Centre (Edinburgh) Substantial modelling capability in foundation geotechnics Extensive engineering capability in seabed remote operations & tooling Strong scientific competence in ecosystem risk assessment