https://www.fortis.edu/blog/skilled-trades/wasted-attic-heat...
I wonder about the option of scavenging heat in the attic during the winter into the rest of the house (through filters) or if it's just a waste of effort.
PCM's (phase change materials) might work better in this application. However, air tightness and a consistent insulation layer is best.
The challenge I've had is keeping the house warm in the winter where internal temps will drop down to the 50s without the heater on. During the summer, I rarely have to turn on the AC even when it's a 100+ day so there's plenty of insulation. I suspect much of the heat loss is due to the giant windows that I have even though they are double pane.