Non-nuclear renewables ("intermittables") need something else as back up. That is almost always natural gas.

That's been causing a lot of problems for Europe for years now.

There's the dependence on Russia, there's the dependence on the North Sea supply -- and the full-scale invasion started while the Danish fields were off-line -- and there's the dependency on LNG imports from actors that are either unreliable (the US) or far away (the US and Qatar) or both. LNG is also quite expensive.