One simple and relatively cheap way Phoenix could be more survivable would be to build underground. The temperature at 12 feet below ground or more really does

One simple and relatively cheap way Phoenix could be more survivable would be to build underground. The temperature at 12 feet below ground or more really doesn't change much throughout the year. The reason they don't do that in Phoenix is that they don't need to dig foundations because there isn't any frost rise or fall at the surface. Since that is the case, the extra cost of digging a basement, which is around 3%, cuts into the margins of large home builders enough that it isn't done. They could also drill into the ground even deeper and use it as a heat sink and pump air through pipes to cool homes. Again this is more costly at construction time, though it would save money for the homeowner and provide protection for the city in gear emergencies, and put less pressure on the power grid. Finally, every home there should have solar on the roof to offset AC charges, and a passive dew condenser to provide extra water for the house. They don't.