It's showing live data. Being nighttime, there is currently no solar generation. If you click on the country and look at the little last 24 hour visualisation you can see solar production peaking at 23% yesterday in Germany.

https://www.electricitymap.org/zone/DE

That's the current solar output at night. The listed solar capacity for germany is 52 GW.

It actually shows live output and total capacity.

Solar capacity is listed at 52GW. Wind total capacity is 61 GW, with an mediocre 15% output.

That’s not a lot to show for 500 billion euros...