Wind and solar are only possible because they use the rest of the grid as effectively a giant battery. When the sun shines and/or the wind blows, someone else needs to reduce the electricity generation. The end result will be that during good weather the price of electricity is zero, and during any other time the price of electricity is high to pay for unused capacity and additional wear and tear on the equipment due to additional power cycling.

We are already seeing this in Germany[1], where electricity prices are also becoming zero[2] during parts of the day. The problem with renewables will become apparent only once the reserves of easily dispatchable electricity generation is used up across Europe to balance renewable generation.

[1] - https://www.nordpoolgroup.com/en/Market-data1/Dayahead/Area-...