I guess it is, but solar can only be part of the answer: You need a solid plan (and all the infrastructure that implementing this plan involves) for when the sun does not shine, because in the more northern parts of Europe especially, energy consumption is highest during seasons in which sunlight is (relatively) scarce.
Also, "the grid" cannot absorb any amount of solar energy - so if you choose to address (at least parts) of the above challenge with a photovoltaic build-out that results in massive excess capacity during summer, there needs to be a plan (and again, its implementation) to handle that.