First internationally certified marine power plant

Scottish company Ocean Green Energy, which specializes in wave energy generation, will be the first company in this sector with full certification from Det Norske Veritas (DNV), the international independent foundation for risk assessment within the marine energy industry.

Aberdeen-based Green Ocean Energy is a step closer to becoming the only marine power company in the world to have its technology fully certified.

The firm’s Wave Treader device will imminently secure Statement of Feasibility from DNV (Det Norske Veritas) – the internationally recognised experts in identifying and managing risk within the energy and marine industries.

This is the first stage of a four part process which would see Green Ocean Energy become fully certified by the independent foundation, an accreditation which no wave energy company has achieved to date.

The unique Wave Treader machine attaches to the transition piece of an offshore wind turbine to generate combined wind power and wave energy, thereby significantly increasing the energy yield of the offshore wind farm.

George Smith, Chief Technical Officer at Green Ocean Energy said: “This is the first stage in an exacting but crucial process and we are delighted to secure initial accreditation for our technology. To date no other wave energy device has gone beyond the Statement of Feasibility. Our commitment to the full independent assessment demonstrates the importance we place on providing our future customers with complete confidence in Wave Treader. It also underlines our confidence in the machine and the ability of our team to deliver a high quality design.”

The company will now work towards achieving certification for the design and construction of its full scale prototype, completion of testing and the deployment Wave Treader at a commercial site.

The certification comes as an independent review of the company by, renewable energy consultants, SgurrEnergy confirmed that Green Ocean Energy is on track to successfully achieve commercialisation.

Simon Luby, Advisory Services Manager at SgurrEnergy said: “The Green Ocean Energy team demonstrated that the company has the required technical, financial and managerial experience to successfully grow a marine renewable technology business and realise the opportunities which their Wave Treader device presents.

“Our independent review highlighted that Green Ocean Energy has a sound understanding of the challenges it faces and a good plan for overcoming these through ongoing research, development and testing to remain ahead of the field in this specific area of marine renewables.”

Construction of the full scale prototype is expected to be completed towards the end of this summer with testing scheduled to begin in the summer of 2011.

Wave Treader is made from standard marine components that are proven to withstand the offshore environment. The machine comprises a fore and aft arm and sponson attached to the transition piece with an interface structure. This enables the Wave Treader to rotate into the wave train and also to move vertically allowing for tidal range.

The motion of the wave strokes hydraulic cylinders which pulse hydraulic fluid. These pulses are smoothed by accumulators before rotating a hydraulic motor and electric generator before exporting the electricity via an export cable.

The first stage of this process is the Statement of Feasibility released by DNV for the hybrid system Wave Treader, which generates electricity from combined wave energy and conventional wind turbines.

The next step will be the certification of a Wave Treader full scale prototype, whose construction is expected to be over by next summer, in order for operations to start in the summer of 2011.

The system, which uses the motion of the waves to increase the energy yield of a wind energy turbine, can be installed in offshore wind farms that are already operating.

In short, this is a pivoting device (about 50 metres long, with the beam of the turbine supporting it on the water surface) that lifts and falls as the wave passes. This oscillation then strokes a system of pressurised hydraulic cylinders that drive an electricity generator.

The project has a capacity of 500 kW and the energy that is generated is exported onshore through the cable shared with the wind farm.