For the establishment of an approximately 400 MW offshore wind farm near Anholt in the Kattegat, Denmark, DHI was commissioned to undertake a metocean study of operational and extreme conditions as part of an environmental impact assessment.

The project site is moderately sheltered with respect to waves and water levels due to fairly small surges and tide and the absence of swells. The variations across the site are fairly limited mostly due to the weak variations in water depth within about 15-20m.

Hindcast metocean data (wind, water level, current, and waves) were established covering a total of 29 years.
Based on the hindcast data extensive metocean analyses detailing operational and extreme conditions were provided including:

• Astronomical tidal levels
• Rose plots and scatter diagrams of wind, wave, and current parameters
• Misalignment of wind and wave directions
• Exceedance probabilities of wind speed, wave height, and current speed
• Weather windows and downtime for combined wind and/or wave conditions
• Extreme value estimates including spatial distribution covering the project area and assessment of best fitting short-term wave height distribution