What many in Germany are calling a disappointing summer is described by meteorologists at the German Weather Service as “weather with strong variability“. In July, warnings of heat, storms and heavy rainfall alternated. “This not only affected holidaymakers and day trippers, but unfortunately also the output of solar power systems in the country“, says Patrick Lemcke-Braselmann, Co-CEO of aream Group SE.

“When will it be summer again?“ sang Rudi Carrell back in 1975. So this lament has a long tradition – but this year it is justified. July was a challenging month: it began with a severe heatwave and ended with thunderstorms and heavy rain. The overall result: July was wetter than it had been in months. Compared to the reference period from 1961 to 1990, precipitation increased by almost 50 percent, and compared to 1991 to 2020, it rose by 30 percent. “The current complaints about the summer are therefore scientifically justified“, says Lemcke-Braselmann.

Sunshine was equally lacking. According to the German Weather Service, the sunlight levels fell nearly one-sixth below average compared to the 1991 to 2020 reference period. Nevertheless, July was overall warmer than the multi-decade average. 

The disappointing summer also impacted the output of the German photovoltaic systems in the aream portfolio: only 78 percent of the target value was achieved. In addition to the lack of sunshine, there were curtailments of around 500 MWh due to slightly below-average performance. The situation was even worse for the systems in Spain, where systems produced only 67 percent of their target. “With slightly below-average irradiation, curtailments of around 2.33 GWh resulted in this low yield“, said Lemcke-Braselmann. The aream plants in Italy, on the other hand, delivered stable performance despite slightly below-average irradiation levels, hitting their July target exactly.

The German wind turbines in the aream portfolio delivered a weak performance. “It was another month of weak yields due to low wind speeds, although there were significant regional variations“, explains Lemcke-Braselmann. The overall yield reached just under 82 percent of the target.