Geothermal heat pumps = dig a 5 foot hole, put coils in constant 50 degree F temperature. Today’s technology offer 20 year payback. Issue is most home owner move in 7. Any home can have one but some locations have better IRR due to climate and or soil conditions.
You can review DOE web site for info or just search web.
I know geothermal large scale power grabs more head lines but the $20,000 home install will yield more energy saving then large scale geothermal projects because the saving can be ubiquitous.
There is little R &D in cost reducing home heat pumps. In my opinion that offers a higher rerun sooner then nuclear.