It seems I wasn't the only person thinking about it, as California is likely to go down that path (at least for the solar cells, if not the storage):
California may soon be the first state in the nation to require virtually every new home be fitted with solar panels.
The mandate, which would take effect in 2020, is expected to be approved by the California Energy Commission on Wednesday as part of the state’s ongoing push to move from fossil fuels to renewable power.
Under the proposal, all new homes and apartments three stories or less would be required to include solar installations. Exceptions would apply to houses built in shady areas or new structures that include other sources of renewable power.
I think that this idea would go over well in at least Queensland, New South Wales and the Northern Territory. I'm not so sure about Victoria and South Australia, where cloudier, wetter winters than the northern States enjoy probably make solar power seem of limited use for several months of the year.The proposal is expected to raise the average home cost by nearly $500 annually over the term of a 30-year mortgage, according to state officials. However, homeowners are expected to save nearly $1,000 a year on their power bills, officials said.