IMHO, the main drawback from them getting a good ROI is that they don't need power as much as I do. Basically, their heavy energy use is with staying warm in the winter...which they use natural gas for. Their power bills are relatively small and, therefore, not much return can be gained by experimenting with turbines and inverters and possibly battery storage.
Here in the south the main energy battle we need to win is fighting the heat in the summer -- which means winning a power battle not a natural gas battle -- which means homemade power can give us a good ROI. (Now that we have an EV and drive it a lot, that's the main battle we have to win with our solar, especially after I made the A/C run more efficiently by using a variable speed heat pump and also a water heater that produces free cold air I duct into the HVAC return to help the HVAC keep us cool.)
I would think long term Geothermal and a passive solar house would make the most sense in the south.
A house with three foot overhangs. 10-12’ ceilings. A geothermal heat pump to take advantage of the fact that the ground temp is 55 degrees.
Then super insulate with an air to air heat exchanger.
Some of those old adobe houses built in the desert of AZ stay cool even when it is 110 degrees. Just like some of those 700 year old stone houses in Sicily stay cool in the summer. Of course, the walls are 3’ thick.