Last year’s offshore wind conditions in the German Bight compared well to the final index average of the preceding 10-year period, according to Fraunhofer IWES.
The final Offshore Wind Energy Index (FROENIX) for 2017 was between -2.0% and +0.9% compared to the 2007-2016 period, Fraunhofer IWES said.
February, March and October were very windy and compensated for the low natural energy yield in January and July-September, which were far behind average and trailing up to 20% behind the corresponding results of the previous ten years.
Regional differences in the index can be traced back to differences in the storm tracks, as well as the importance of coastal effects, the German research center said, emphasizing that offshore wind farms located farther from the coastline are characterized by positive wind indices, while those closer to land show slightly negative ones.
The findings are said to be confirmed by the comparison of FROENIX simulation data with the information about the production of a number of wind farms in the German Bight.
The index, updated in late spring every year, is based on mesoscale simulations of more than a decade with a resolution of 30min. The horizontal resolution of the simulations is 2.1km.
It can also provide additional and more detailed data, such as time series, wind fields, and statistics and offer different options for evaluating wind farm performances based on the results of the wind field analyses, Fraunhofer IWES said.