I don't know about Belgium. Maybe air conditioners there are more common?
In Germany, it is said that cold winters are more dangerous for the energy balance, as the cold also increases energy demand and the photovoltaik-cells aren't as useful as in a hot (and sunny) summer.
Thanks. I didnt get that fully, because i saw that reply as phrased as a critic to my statement, whereas it supports my point (which was, that high demand/low availabality because of the summer is unlikely in that scenario). Or not, but it is not a real critic on my statement.
Of course such scenarios happen, especially the situation you described.