There are really three options for reliable baseload: coal, gas, nuclear. Pick your poison.
And yes, I realize how well positioned Norway is for this. But you can put these wherever you have a stream and a big reservoir
1: https://energifaktanorge.no/en/norsk-energiforsyning/kraftpr...
We already do that. France notably has a lot of hydropower and they pump water up when they don’t want to shutdown a nuclear unit.
The issue is that there is very little places where you could build new dams in Europe and water shortage is becoming a regular occurrence.
Yes water shortage might be a problem if the river you're on runs dry. That's not often a problem though, plenty of major rivers. And a dam doesn't change the total amount that flows, it just changes when. As a result it might even help in lowering some flood risks.
It's also the oldest storage tech and I doubt there's a single place in Europe available to build more.
> Also in a connected grid setup, the sun always shines somewhere though that does come with potentially huge transmission losses from distance
The whole EU is in winter weather together.
Batteries aren't the only storage. The better options in my opinion are the places where you can use the landscape to your advantage. Pump a lake full when there's too much power and let it drain when there's too little.
Also in a connected grid setup, the sun always shines somewhere though that does come with potentially huge transmission losses from distance