>>11241366Or you could just build your house partially buried in earthworks and let your floors be the heat exchanger.
I've got plans in my head for a really spacious, inexpensive post modern hobbit hole type home I'll build if I ever get a little bit of cash.
With some rebar, air bags, canvass, and concrete you can make domes really easily. Connect those with hallways, run some conduit and your plumbing, and then cover everything with soil and gravel. You could terrace the slopes and do some nice landscaping or gardening.
Put some skylights in the top of the domes, and windows on the outside walls to let in natural light and it would be pretty comfy.
Since the earth itself is maintaining a nice even temperature year round your power consumption would be pretty low so you could live off the grid with it.