Key Features
- Over 500 KW rating for a relatively small ocean footprint
- 50m long, 20m beam, 20m draft.
- 20 Machine Wave Farm giving 10MW typically takes up 0.70km x 0.33km giving 43MW/km2.
- Proof of Concept is complete.
- Very few Single Point Failure modes will lead to a high level of reliability.
- Standard, Proven Marine Construction – Steel & GRP.
- Major mechanical components are standard Marine Specification ‘off the shelf’ items.
- Modular design means ease of component change-out.
- Simple design will mean low manufacturing costs and high reliability.
- Low levels of intrusion to the marine environment.
Market
- Ideally Ocean Treader can be deployed where the following conditions apply:
- Water Depth 50m – 100m.
- Less than 3NM (5km) from the shore line to minimise cable lay costs and for ease of accessibility.
- Exposed location ensuring high wave energy levels.
- Clear of major shipping channels.
Timescale and Funding Requirement
We are currently fund raising to allow a full size prototype to start offshore testing in 2011.
Awards & Grants
This work has received a SMART award as well as other grant support from Scottish Enterprise, and we expect continuing support and encouragement from the public sector.
Ocean Treader - OverviewOcean Treader is simple in concept, efficient in operation and robustly designed to withstand the aggressive environment of the North Atlantic Ocean. It uniquely harnesses the different responses of horizontally and vertically floating bodies to passing waves and is protected by International Patent applications. We have proven the concept in tank testing and using a combination of that data and real wave data Ocean Treader’s projected p/KWhr figure is considerably lower than other WECs we are aware of. How it WorksOcean Treader comprises a Sponson at the front, a Spar Buoy in the centre and a second Sponson at the aft end. As the wave passes along the device first the forward Sponson lifts and falls, then the Spar Buoy lifts and falls slightly less and finally the aft Sponson lifts and falls. The relative motion between these three floating bodies is harvested by hydraulic cylinders mounted between the tops of the arms and the Spar Buoy. The cylinders pressurise hydraulic fluid which, after smoothing by accumulators, spins hydraulic motors and then electric generators. The electricity is exported via a cable piggy-backed to the anchor cable. Ocean Treader is directional and has been proven to passively weather-vane to face the wave train, and it also has active onboard adjustment to allow for offset due to the effects of current. Scale model weather-vane tests at Strathclyde University DesignThe structure comprises of steel load bearing members with the buoyant bodies molded from GRP (Glass Reinforced Plastic), this allows standard offshore manufacturing techniques to be used. The machine is also modular which allows for great flexibility in the manufacturing process. ReliabilityDue to the machine's remote eventual locations where access will not always be possible, reliability has to be one of the key features. This is first the product of good design and the design team’s 20 years of experience in offshore structures and machines will be key to this aspect. Secondly all the hydraulic and electrical equipment will be to standard, industry proven marine specifications, and thirdly the systems will be assembled by experienced and skilled personnel. In the design of the machine care will be taken to minimize the possibility of single point failure modes. Wave FarmIt is anticipated that these machines will be deployed in farms of 10 – 20 machines. Because of the low lying aspect of Ocean Treader and because they will typically be one to two miles offshore, visual intrusion from the shoreline will be insignificant, a major benefit. |