I’m not familiar with NordPool specifics but this is exactly right and is playing out in California and elsewhere too. Basically just the duck curve. Storage is all but required as solar covers 100% of midday load.

Is it a bribe or ransom? Trump is extracting favors by threat.

Maybe the study was more robust that this article suggests, but this doesn’t tell me anything. Humans are amazing at regulating our remperature via sweat, so I have zero doubt that normal healthy people will have the same internal and even skin temps wearing different color clothing in different conditions. If the group wearing e.g. dark codlors just sweat X% more to compensate, we can’t draw any conclusions at all. Clothing is complicated, since airflow and moisture retention matter significantly, but we know for a fact that lighter colors reflect more energy than darker colors.