A rainy August was followed by a dry and relatively sunny September in Germany. In contrast, the wind blew rather lukewarm again last month. "For investors, it is therefore important to have a good investment mix in terms of energy forms and locations", says Markus W. Voigt, CEO of aream Group.

In September, production from solar energy in this country was 89 percent of target. The harvest was better in southern Europe: Spain managed a precision landing last month with a production of 100 percent of the target, and in Italy the yield was even 102 percent. In terms of wind, German turbines achieved only 61 percent of their target values. 

Wind strength and solar radiation change from month to month - and so do the energy yields from renewables. However, over the long term and across different locations and forms of energy, there is usually a balancing out. "To prevent the weather from causing portfolio yields to fluctuate so much, diversification is indicated when investing in renewables", says Voigt.