You searched for: “geothermal drilling
geothermal drilling (s) (noun), geothermal drillings (pl)
The process of drilling a well to explore for or to extract geothermal energy, or to re-inject thermal waste water in the ground after power generation: Geothermal drilling entails boring a hole deep into the ground and pumping water back up. The method of geothermal drilling is a fantastic way of heating one's home.

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