[sph]

Additionally to what the sibling commenters say, we don't have a lot of sun nor wind in the Po Valley, where most of the industries are, and please point me to any G7 country that produces most of their energy from hydroelectricity, which Northern Italy has a decent potential for.

Renewables are just now starting to become economically viable, but distribution is still an unsolved problem. The wind farms in Sardinia are not gonna power Milan.