Scottish Marine and Freshwater Science Volume 3 Number 2: Scoping Study For Offshore Wave Energy Development In Scottish Waters

2 Approach

As was the case in the development of the Scoping Study for the Saltire Prize programme for wave and tidal power development, and parallel documents for wind energy, Marine Scotland has worked with The Crown Estate to use MaRS for the identification of potential areas for offshore wave power development .

As previously mentioned, in order to apply the MaRS tool, it is necessary for the user to make a number of decisions regarding the data to be included in the models and the way in which the data are to be handled. These decisions include factors such as:

• The factors that require consideration when locating wave energy developments and the availability of spatial data that can be included in the models.
• Whether particular activities or uses should be considered as incompatible with wave energy development, or whether activities or uses should be considered as presenting gradations of limitation to development potential.
• The relative importance (weighting and scoring) that should be applied to the different layers of data in the final integrated model.
• The relative quality and reliability of data layers.

Building on experience of the Scoping Studies for the Saltire Prize, and, the data layers were grouped into themes ( e.g. technical, industrial, environmental, socio-cultural). This procedure minimises the conceptual problems associated with defining appropriate relative weightings for very diverse types of data ( e.g. the relative weightings of seabird colonies, fisheries landings, and basking shark sightings). The thematic grouping allows assessment of the sensitivity of the outputs to variation in the overall weighting between themes. This approach had previously been used successfully in the Scoping Study for the Saltire Prize, and also in the Scoping Study for Offshore Wind in Scottish waters (Davies and Watret, 2011). A similar approach has therefore been adopted in the current study, grouping constraints layers into themes representing constraints arising from industrial activity, environmental factors and socio-cultural interests.

The modelling for this wave energy scoping study built upon the experience gained in the Saltire Prize modelling and subsequently in the Sensitivity Analysis (Davies and Aires, 2011) and updated Scoping Study for offshore wind (Davies and Watret, 2011). The wave study adopts a similar separation of data layers between constraint and exclusion models, to maintain a balance in the influence that different data layers have on the model outputs. Further efforts were made to ensure that the scoring systems for the various layers followed the statistical advice within the MaRS modelling guidance, and that the scoring system for statistically skewed data sets was appropriate, both in the resultant influence of the layers in the models and the degree of discrimination between areas. Where possible, improved or updated data layers were used in the current Scoping Study, as indicated in Section 3.