Industrial scale geothermal works fine where the crust is thin. (Hawaii, Iceland, Japan, Yellowstone etc.)
Solar would be used in places where there is lots of sun to melt salt. (Like death valley, Saskatchewan, the Sahara desert, most of the middle east, the Gobi desert, the Atacama desert.)
Nuclear could/should/would be only used where the crust is too thick or where a source of water is problematic.