Off-shore Wind Atlas of the Central Aegean Sea: A simple comparison of NCEP/NCAR RE-analysis data, QuickSCAT and ENVISAT Synthetic Aperture Radar (SAR) by use of Wind Atlas Method

Offshore wind energy is progressing rapidly in many parts of the world including Europe. While our understanding of offshore wind is growing parallel to that, most of the offshore wind development is located in shallow or transitional waters. Deep, open sea was never preferred by developers due to high costs, but with the new developments in floating turbine design, it seems that offshore wind parks in deep waters will also be a possibility in the future.

Whether on-shore or offshore, the first step of a site assessment is to estimate the wind resources. Usually well-known conventional methods are used to produce estimates of wind resources by means of at least one year data from a single or multiple points on the terrain. This criterion is dicult to satisfy in offshore locations where measurements are costly and sparse.

Therefore other methods are required (e.g satellite imagery or reanalysis model results). Unfortunately all of these methods are still under development and do not provide data acceptable for bankable wind assessment reports. On the other hand, they give good indications of the geographical distribution of the wind resources and that is very useful for decision making and planning of feasibility studies and of actual project preparation.

Until now, several offshore wind resources (e.g. North Sea [1], Baltic Sea [2]) have been investigated by means of ENVISAT Synthetic Aperture Radar (SAR) data. In the current study we investigate the positive and the negative aspects of using SAR data at the Central Aegean Sea and compare with two other parallel developing techniques; NCEP/NCAR re-analysis based Ocean wind Atlas and scatterometer winds QuickSCAT 1.

WAsP software and/or method is used in all steps of the study.