The media story that for the first time more solar energy was producted than nuclear energy was hilarious when one understood the situation or when one had some background. The others where put on the wrong track. This was clear from the non-critical comments on that article. For example this very condensed comment of someone coming to the defense of solar panel owners (translated from Dutch, interpunctuation added by me for clarity reasons):
and then complaining about people with solar panels, happy we have these people, otherwise we were again without power
This reaction was made in the light of the criticism on people with solar panels. They received this criticism already some time because they make the energy invoice more expensive, but this was recently stirred up again when our current federal government decided to increase the energy price and one (rather large) part of that cost is the financing of green certificates (is an amount of money paid to panel owners for each 1,000 kWh produced). Which explains the “complaining about people with solar panels”-part of the comment.
The second part was a bit harder to understand. The commenter apparently understood the story from the media as:
nuclear power reactor gets offline → solar energy had a good day and took over → Hooray! A victory for solar power in Belgium!
However, that is not what actually happened in the real world. This is what happened that day:

Sources: Nuclear + wind: http://www.elia.be/en/grid-data/power-generation/energy-cipu-units | Solar: http://www.elia.be/en/grid-data/power-generation/Solar-power-generation-data/Graph
The reactor got offline just after midnight. Obviously, it was pitch dark back then and solar panels didn’t produce anything yet (they don’t work on moonlight and the result of their production was a perfect round number). So something else obviously took over or the margin was wide or probably both.
If solar energy was the savior when the nuclear reactor failed, then where did the energy to accommodate the morning peak come from when solar power was neglectable? At 07:00 electricity production (and electricity import from abroad) peaked in the morning. At that peak, solar contributed only 62 MW, only 4% of the nuclear power production at that moment. The same thing in the evening: where did the energy needed during the evening peak come from when solar dropped below that magical threshold of nuclear production? At the evening peak, solar contributed somewhat more than 6 MW or 0.4% of nuclear power production at that time.
More, at this stage of summer the sun is rising rather early (around 06:30) and goes down rather late (around 21:00), but this is different in winter where the sun comes up around 08:45 and goes down around 16:45. When this would happen in winter, solar energy wouldn’t contribute to our energy need at peak hours. Not even 4%. Not even 0.4%. Because it would be still dark when the morning peak starts and it will already be dark before the evening peak starts. That is what made the treath for blackouts in the winter period. In winter we need more energy than in summer, especially in the morning and evening peak when we need most energy, yet at that moment alternative sources perform rather badly.
Essential to understand the story is the time the reactor went offline (if that was communicated, people could connect the dots themselves), but also the exact time frame that solar energy rose above that threshold and exactly which source(s) came to the rescue. For some reason none of these were reported by the media. They focused solely on cheering, without looking at the big picture.
I looked at that electricity generation data before and therefor I knew something was really wrong the moment when I read the article. But for those who relied solely on the media for their information on this subject, the proposed story seemed really plausible. It is completely in line with what the media is telling about the subject, so for the public it seems logical that those solar panels performed excellent and saved electricity production that day.
The curious thing is that solar energy didn’t do much special that day. It just did relatively better because a nuclear reactor went offline and that non-issue was considered good enough for a headline…
This was not only the failure of a nuclear reactor, but also the failure of the media to inform the public about the facts.