Onshore Full Scale Power Take-Off systems Test Facility




Wave energy converters are generally placed in very harsh environment and are hard to access due to their location and/or unfavourable weather conditions. With this in mind a full scale wind tunnel test facility capable of simulating a variety of wave heights and wave periods has been built to fully test and validate the Power Take-Off system (PTO).  The test facility will enable the company to fully test and validate the systems performance and reliability in a variety of sea conditions, thereby de-risking the system before it is deployed at sea.  Significant cost savings are achieved by commissioning and adjusting the PTO on land prior to its deployment at sea.  For demonstration purposes, the facility is also equipped with the capability to demonstrate the PTO system’s capacity to generate real time electricity.

The power take-off of a wave energy converter is defined as the mechanism with which the absorbed energy by the primary converter is transformed into useable electricity.  The PTO system is of great importance as it affects not only directly how efficiently the absorbed wave power is converted into electricity, but also contributes to the mass, the size and the structural dynamics of the wave energy converter (WEC). 

By having this direct influence on the wave energy converter, the PTO system has a direct impact on the levelised cost of energy (LCoE).  The PTO system has a direct effect on the efficiency of power conversion; hence, it has a direct impact on the annual energy production.  The reliability of the PTO system affects the availability (the energy production) and the operation and maintenance cost.

Our PTO system has undergone step changes and modifications from the experience learnt through rigorous modelling, tank testing and validation in real ocean environment.  We have now built a robust and reliable commercial PTO system that requires very little maintenance throughout the 30 years life design of the system.  The PTO system, designed to operate in all sea conditions, is now ready for onshore demonstration at full scale.  It is 100% environmentally friendly, with no negative impact on marine life and no oil or other contaminants.

To ensure the cost-effectiveness of the WEC system, a control strategy is carefully designed for the PTO system to respond to the irregularity of each incoming wave by adjusting the stiffness and the damping of the PTO system.  With a simplified design and highly efficient air turbine, the efficiency of the system is thereby increased and hence its cost-effectiveness.

The same PTO system is used for all product ranges of our wave energy converter technology, shallow water and deep water applications, with small adjustments to suit any given project location.   

The PTO system will be showcased between May to August 2017.  The full scale 1MW WEC is scheduled for deployment at sea at the end of 2017.

Oceanlinx plans to build and commission a 1MW greenWAVE demonstration unit in an Ocean Energy Testing and Demonstration Zone which was established by National Taiwan Ocean University (NTOU) in sea area of Keelung ,Taiwan. The Zone was approved by Central Fishery Agency, Keelung City Government and Local Fishery Association for demonstrating ocean energy technology, and there were already one ocean energy technology tested two times in the Zone for the past two years.

At the end of 2014, Oceanlinx and NTOU signed a MoU which allows Oceanlinx to build its demonstration unit in the Zone. NTOU will not only assist Oceanlinx to undertake detailed site investigation but also undertake local consultations with local fisheries and local government together with Oceanlinx based on its long term relationship with the stakeholders.