Maybe I'm failing to follow the intended argument here, but I do not see what is expensive about this. Houses are hollow; they do not weigh all that much. Dirt is cheap, especially when sourced locally.
> A typical site is a factory, power plant, or town with a large earthen mound at the edge. The mound might be the size of a house for a smaller factory, and up to many football fields for a large power plant. Surrounding the earthen mound will be high-density, low-profile solar arrays.
I agree that trying to give every suburban house its own rock pile would not be very practical.
I know. See my original comment at the top.