Germany hits the August doldrums
Data derived from nearly 12,000 wind turbines with a combined installed capacity of more than 16.5GW in Germany and Denmark confirms that wind speeds varied widely across the two countries during August. Figures published by consultancy AWS Truepower in its Wind Trends Bulletin for Q3 2016 show that while wind speeds across most of Germany were 2.8% down on the August average, they were 7.2% up in Denmark.
The result appears to be another poor month for German wind-power production, with an average capacity factor of just 12%. While that is marginally better than June's 9%, average German capacity factors have been bumping along below the 20% mark for six consecutive months. You have to go back to February to find the last time they hit 30%.
Denmark enjoyed rather better weather for wind-power generation during August, which is clearly reflected in an average capacity factor of 27%, its best figure since February and a substantial improvement on the 17% recorded in June.
The difference between the wind resources the countries experienced makes comparison between manufacturers' performance difficult to quantify. Vestas' strong presence in its domestic market is probably the factor that gave it the edge over other makers, with an average capacity factor from its range of onshore turbines of 15.6%. Closest rivals were GE on 14.6% and Senvion on 14.3%.
Low-wind specialists Enercon and Nordex, much better represented in Germany rather than Denmark, achieved average capacity factors of 13.1% and 11% respectively.
Regrettably, a glitch in the database means we are unable to provide an average capacity factor for Siemens turbines for August, although figures for some individual models are available (see chart below).
Enercon in the right place
Several types of turbines produced an impressive degree of output for a European summer month, although it must be assumed they were either mainly in Denmark or the northern tip of Germany.
Enercon's 3.05MW, 101-metre rotor diameter turbine, designed for IEC IIA sites, topped the table in August with an average capacity factor of 37%. This surpassed even the 3.6MW Siemens offshore turbine, which registered an average of 36%, and which interestingly, out-performed its 6MW big brother during the month.
The 2.4MW Nordex turbine with a 117-metre rotor diameter and optimised for low-wind sites, was another impressive performer during August, recording an average capacity factor of 35%.