I have been both to this site and to Coober Pedy, South Australia. Pretty neat bit of architectural convergent evolution for extremely high temperature environments.
> It astounds me that these things do not catch on.
Basements are very common throughout the country. Once you've built a basement, you might as well put a house on the next floor up.
Modern insulation technology is very effective. It's much cheaper to put a lot of insulation in the above-ground portion of a house than to try to build the equivalent area entirely below the grade.
Building entirely below the surface without putting anything on top would be massively expensive compared to the same square footage in a traditional home, even if you accounted for equivalent insulation and cooling costs. It's not even close.
I lived in Fresno for 15 years. I spent north of $400 bucks a month on AC in the summertime (starts in June and goes till early November). I lived in a new home with modern insulation.
I now live in NY and I have a basement. It's generally about 10 degrees cooler. I would have loved that in Fresno.
Electricity in California is the most expensive in the country. When I lived there I spent between 20-35c/kWh. I moved to Utah and now pay approx 9c/kWh, cheaper by a factor of about 3. I live in the Southwest part of the state where the temperatures regularly hit 46c and my electric bill comes out to about $100.
I think that underground or earth bermed homes are often failures. There are different water and ventilation concerns for these. An above ground home is pretty accessible for repairs, but these can be nearly impossible if the home is underground.
This is what kills most "non-standard" homes and buildings - anywhere in the world.
If you build an American-style house in Bavaria it may end up a disaster because nobody around knows the building materials or how to fix it.
It gets even worse when it's entirely custom like this Skywalker style house, where it's a one-off using techniques nobody knows. You need a dedicated maintenance crew for that so they can learn all about it over time.
So something like this could work for a largish company, or a college campus, but as a one-off house it's going to be expensive and eventually abandoned.
I wonder if there aren’t zoning laws that create incentives for or against some of these approaches. In dry places the living space can be connected to rain-collecting cisterns that further help to reduce evaporation losses. When you free the surface to other uses, you can also generate power from wind or solar (and solar also helps to protect the top soil from evaporative losses).
> In a hole in the ground there lived a hobbit. Not a nasty, dirty, wet hole, filled with the ends of worms and an oozy smell, nor yet a dry, bare, sandy hole with nothing in it to sit down on or to eat: it was a hobbit-hole, and that means comfort.
> ... The best rooms were all on the left-hand side (going in), for these were the only ones to have windows, deep-set round windows looking over his garden and meadows beyond, sloping down to the river.
It does not astound me. Building things underground is expensive and in a lot of cases not cost effective compared to the cost of electricity at human scale.