[bbarn]

Solar with Battery storage is a very useful source for heating energy, even in the coldest climates in CA. Even in the mountains where it drops below freezing at night, most places it's still sunny a lot more than the US average during the day. Most Battery setups I know of target a 4 day stretch of cloud cover for storage capacity, so it is certainly an option.

Where I live at 7000 feet, we have so much sunshine, even in winter, solar is a very viable option. Legislation removing people's ability to recoup the costs is the only reason it's not in every house in the city. The only option left is a much more costly battery setup.

[PaulDavisThe1st]

Where I live, at 6200 feet, we have oodles of sunshine. Even so, the air-source heat pumps in my old adobe use 3x more than we generate (which in turn is 3x more than we need during the summer). No (sane, residential) battery system can handle this.

Which mostly goes to show the value and necessity for serious insulation and air-sealing, which this house does not have. Nevertheless, the point about batteries remains.