Capacity factors and load-duration curves for Belgian offshore windfarms

Posted by – 2017/09/26

Previously I’ve provided capacity factors for Danish, German and UK offshore windfarms. Now here are the numbers for the larger of the Belgian offshore windfarms. The ones shown here are the only ones I’ve been able to get detailed data for, so far.

Belgian offshore wind

All numbers are to the end of August 2017. Analysis by
Jan 2015
Age (y)Installed
quantiles TO HIDE
Thorntonbank NE28.6%32.8%4.6159
Thorntonbank SW33.6%36.4%0.3-4.6175

Data weirdness

There is some strange data for Northwind: it behaves fine in 2015 and 2016, but then, in 2017, reported generation starts getting above the rated capacity of 216 MW … and keeps growing. To construct the statistics here, I’ve removed the data from January 2017 onwards. If anyone’s got any ideas on how to get something usable from that data for 2017, please let me know via twitter @EnergyNumbers.

The Thornton Bank windfarm was built out in three phases, I-II-III. However, the hourly data is broken down into two groups, SW and NE. As you can see from this map, courtesy of 4COffshore, most of phase II is in the NE section. The SW section contains the rest of phase II, as well as all of phases I and III.

Load duration curves

I’ve constructed for each of the offshore windfarms for which there is detailed hourly data. Use the pause and play buttons to stop and start the sequential display of curves. Click on the windfarm name in the legend to toggle the display of that farm’s curve.


Note that for each individual windfarm, its curve is based on data starting from the date that the windfarm was fully commissioned, and the windfarm’s age is calculated as starting at that date.

Windfarms less than a year old are excluded from the calculations of the power density per unit area spanned. The figure for total power density is a weighted average of the windfarms that are a year older or more: this is weighted by size, but not by time. So a windfarm that’s twice as large contributes twice as much to the total; whereas a windfarm that’s twice as old, does not.

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