Version 2 of "O&M Simulation Tool" available for download, see O&M Model Modification Log for details

Wave energy developers have found that an O&M simulation model is an extremely useful tool for three primary reasons:

1. At early stages of development, an O&M model can help identify critical components which would have the biggest impact on array performance, thus providing feedback into the device design
2. The tool provides estimates of array availability, revenue and operational expenditure which helps to refine Levelised Cost of Energy (LCOE) calculations
3. As device development moves towards real sea testing, the tool can assist in planning aspects of the O&M strategy for future arrays.

WES now has an O&M simulation model which was developed by Anthony Gray under his EngD research project. This project was sponsored by WES through the Industrial Doctoral Centre for Offshore Renewable Energy (www.idcore.ac.uk). The model is now available for download and is supported by full explanatory documentation to make it ready for use and further development by the sector. WES would like to receive feedback on the tool and would welcome sharing of further user developments to extend this open source resource.

This Microsoft Excel-based O&M tool uses the Monte Carlo method to simulate the occurrence of faults on each device in a wave energy array by utilising failure rate data. All the components of the device are represented by fault categories, assigned following a Failure Modes and Effects Analysis (FMEA) of the wave energy converter (WEC).

The user can choose whether certain faults can be repaired whilst the WEC is offshore, or if all faults require the device to be towed to the safety of a sheltered quayside or onshore O&M base for repair. This ‘reactive’ maintenance modelling is coupled with the option to include modelling of ‘proactive’ routine servicing of WECs. Maintenance parameters, such as repair times and parts costs, are defined by the user, as are other aspects of the O&M strategy, such as weather limits for marine operations.

The model utilises a time series of weather conditions in order to assess windows of accessibility and calculate revenue generated by the array at each time step. The model simulates the array lifetime as realistically as possible by enforcing logistical constraints, including technician availability and quayside access. A full breakdown (per device and per year) of outputs including availability, revenue and operational expenditure is presented, as well as a table attributing costs to each fault category.

The following documents will assist with running the model:

• User Guide
• Functionality Report
• Weather simulation (included in the "User Guides" download)
• O&M Model Modification Log