Yes, by far. It’s much easier to extract heat from ~55F ground water than from ~20F exterior air. Ditto for dumping excess heat into ~55F ground water than 90F

Yes, by far. It’s much easier to extract heat from ~55F ground water than from ~20F exterior air. Ditto for dumping excess heat into ~55F ground water than 90F exterior air. On average the water coming out of a geothermal loop will be more advantageous to work with than exterior air, which is why it’s a thing.