Wave energy developer Carnegie Wave Energy Limited announces that the three CETO 5 units have now accumulated more than 7,500 continuous operating hours.

The first CETO 5 unit has now been operating for over 4,000 hours, with the second CETO 5 unit achieving over 2,000 operational hours. The third CETO 5 unit was installed at the project site in early March and has now been operating alongside the two other CETO 5 units for over 1,000 hours. During the 7,500 continuous operational hours the units have experienced a range of sea states, including waves up to 4m in height, the company reported.

Additionally, following connection to the grid in February, an initial period of grid commissioning, data collection and analysis has been completed and provided to the grid owner, Western Power, and the Perth Project has now been deemed to comply with Western Power Technical Rules. This allows consistent power generation and export to the grid to proceed.

Maintenance

The operation and maintenance activities during the project are conducted by Carnegie’s Operations and Maintenance team and to date have included regular offshore inspections – through diving and remotely operated vehicles (ROVs) – as well as onshore activities such as the maintenance of plant and equipment and monitoring of working fluid cleanliness.

Carnegie had previously planned to retrieve one of the first two CETO 5 units at the same time as the deployment of the third unit however, this was deferred to allow all three units to operate as an array for a period of approximately 30 days. This period has now been reached, and preparations have now started to retrieve CETO Unit 1 and Pod 1 for a complete strip down, inspection and overhaul.

Planned retrieval and inspection activities also allow for more informed operation and maintenance activities ahead of winter and include the removal of biofouling, inspection of seals in the CETO pump, inspection of bearings in the load path components and repair of some failed instrumentation. Importantly, the retrieval of CETO Unit 1 provides an opportunity to verify the retrieval method which is a key input into the ongoing operating philosophy associated with the Perth Project and CETO 6, the company said.

Performance

In order to effectively assess the performance of the CETO 5 unit, Carnegie has equipped the CETO units and the balance of plant with approximately 500 sensors generating 4 GB of data per day. This allows performance data such as pressure, flow, displacement, power, load, position and the like to be recorded and transmitted. This data is also used by the Process Control System and the Plant Operators to control the units and system response to optimise the overall performance of the plant. This optimisation process is now underway for the Perth Project, Carnegie informed.

The analysis of the data is being done in-house by Carnegie’s technical team, who were also responsible for the design, procurement, integration testing and commissioning of the Perth Project. It is estimated that the performance analysis process will be completed later this year and an independent review will then be undertaken to ensure the integrity of the analysis work.