I think you are talking about geothermal energy hooked up to a heat pump. Works well I'm told. You can also go vertical into the ground with it. https://en.w

I think you are talking about geothermal energy hooked up to a heat pump. Works well I'm told. You can also go vertical into the ground with it. https://en.wikipedia.org/wiki/Geothermal_heat_pump https://en.wikipedia.org/wiki/Geothermal_heat_pump