The deployment and operation of wave and tidal farms is expensive with installation costs representing 18% of lifetime costs for wave and 27% for tidal arrays. These costs depend significantly on the site and foundation requirements. The higher proportion for tidal devices is due to the challenges of installation in high speed tidal currents. Installation costs form a significant proportion of the initial investment, making them a key priority for improvement in order to facilitate future and larger deployments. Operational costs are also a key concern, although with little full-scale practical experience, it is difficult to quantify the potential costs at this stage. However, it is estimated that O&M costs make up 17% of lifetime costs for a wave array and 19% for a tidal array. To place this in context, the annual O&M of wave and tidal devices is expected to be c. 3.4-5.8% of CAPEX compared to 2.3-3.7% for offshore wind. It is also important to consider the potential impact installation and O&M methods may have on array design e.g. the spacing needs for vessel access. To date, few studies have investigated the costs, infrastructure and resources needed or the time required for installation or O&M activities. The Selkie project will examine –
This WP will use existing installation, O&M and logistics models that have been developed primarily by UCC for the offshore wind industry and begin the process of modifying them for use in wave and tidal applications. In the process of model development, it is planned that workshops will take place with external IW industry stakeholders. This ongoing consultation will ensure industry relevance of the functionality of the software tools; the validity of the software outputs and assumptions; and awareness of the Selkie project tools by industry. The model development will also draw from work undertaken in the DTOcean project which developed a 1st generation set of open source models applicable to the wave and tidal sectors. The tools developed by DTOcean are open source, and are basic models. The open source code allows the user to customise the model to specific or tailored requirements of the technology or company, by researchers and developers.
After the consultative and review of existing all modelling is complete, tool development and customisation will take place with the purpose to provide a user-friendly Installation, O&M and Logistics software that can be applied to a variety of wave or tidal technologies
As wave and tidal energy are nascent industries there is very little experience in designing and operating commercial farms so significant learning is required before the benefits of full optimisation can be achieved. However, the development and use of models can ensure that there is some level of optimisation, particularly if the experience and methods used in the offshore wind industry are used.
Thus the developed models will allow the user to 1) optimise the logistics required at the installation and O&M phase e.g. port, offshore vessel fleet, activity schedule and 2) simulate operations across the lifecycle considering uncertain factors e.g. weather and failures and their impact on the costs and duration of a project. This set of tools will enable not only design of optimum supply-chain for a given ocean energy array, but will also provide input to total life-cycle supply-chain cost assessment by linking with the techno economic model. The work will draw on previous experience on the development of similar models for the offshore wind industry where there are similarities in terms of the logic and methods that need to be employed.