Right there, in your pics, is the type of “alternative energy” that I keep pointing out to people is THE best starting point: using the earth to reduce heating/cooling requirements in a completely passive fashion. Using ICF’s gets you an added bonus.
Next, I’d recommend that people look at some of the most recent studies on heat loss in domestic structures coming out of various labs. One of the biggest causes of heat loss (once we get by the obvious: doors/windows/insufficient insulation) is the technique of using wall studs that connect to both the inside wall and outside wall. I’ve seen some papers recently on a house constructed with 8” walls, but using 2x6” studs. They alternate the studs - every other stud is nailed to the inside wall, but not the outside wall, and vice-versa. Turns out that when we get into thicker walls with modern insulation, the studs connecting the inside wall to the outside wall conduct more heat out of the house in winters than one might imagine - until we look at it with an IR camera. Then the relative insufficiency of the wood as an insulation compared to the wall fill stands out like a sore thumb...