What attracted me to geothermal was the year round availability of 50F water - easier to extract winter heat at that temperature, and you could create a simple

What attracted me to geothermal was the year round availability of 50F water - easier to extract winter heat at that temperature, and you could create a simple fan / radiator ducted air cooling system for the summer. The latter would actually store summer heat in the ground, and could be powered purely by solar.