Comment by weberer

Yeah, the batteries are for wind. There are some days when the wind barely blows at all. That's when electricity prices really spike.

Finland's power grid stats are open to the public. You can click the month view to see how the different power sources fluctuate.

https://www.fingrid.fi/en/electricity-market/power-system/

Also fun fact: a lot of solar panels in Finland are mounted vertically to walls rather than rooftops. That's because we're so far north that the sun just hangs around the horizon rather than going directly overhead. You end up catching more sunlight pointing directly south.