It would be really easy for governments to change their building codes and make it mandatory for every new house, apartment building and commercial building to have a solar power system including a car charger. It really doesn’t add much to the cost of building and if it is a mandatory then no one will notice the cost (same as conforming to drainage and engineering standards-it is what it is). As it is currently, solar power is an option and is considered ‘additional’ cost and then people choose either not to add it, perpetuating reliance on fossil fuels, or to do it later and then never get around to it or can’t afford it. But if it is a non-negotiable then it gets factored in as a matter of course and not thought of again. Within a few years we will look back and wonder why it wasn’t done from the start.