That is a nice system, solar is a good way to go for a lot of our needs.
And if one can’t afford the fancy solar systems, there is always a fire in the front yard and a bucket with water to heat it.
Or as I have to do, as I can’t use my wood stove and be on my oxygen machine at the same time, and I pass out, so don’t play much with fire, you will wear 3 layers of clothing, wear a layer of plastic and keep your head covered.
If it gets too cold to sit up, the bed is there with its sleeping bag and a plastic bedspread [a good Walmart paint drop cloth] to seal the body heat in.
One survives, if one wants to do so.
My old wiring will not support electric space heaters.
I have found in an emergency situation that a layer of newspaper between layers of clothing does wonders at keeping in heat as well. On motorcycle road trips when we’d be out too late and get chilly or an unexpected norther would hit before getting home we would stop at a convenience store and pick up a Thrifty Nickel and place half the paper under the back and half the paper under the front of our outter layer of clothing. Good warming stuff. Even riding at 70MPH.