Yeah I get all that, but what if I need heating in the winter and have very low consumption in the summer? That is why I'm searching for real world numbers. If you give me some for a specific place then I can at least have a ballpark number if what I might get where I live.
OTOH as you say, they start to be so cheap it's almost impossible to go wrong...
Smart planning! Thanks for the story, are you planning to go off grid or is it just to be economically free? Any batteries in the future? Excellent reference, and implementation, I'm giving you an 11 out of ten!