[Bedon292]

Drilling to the depth needed to get high enough temperatures for energy generation can be hard. Depending on how active the area is. Iceland, which has tons of heat close to the surface can do it with relative ease. But elsewhere you may have to be drilling far deeper through much harder rock to get there. In some locations you may have to drill down many km at 10s of meters per day through the hardest rocks. It could potentially take months to hit the right depth.

You also need materials to ensure that the well doesn't collapse on itself, and stuff like that as well. I would expect the hole itself should have an extremely long lifespan, but I don't really have much to back it up.

Its not for electric generation, but for Geo HVAC the ground loop itself has a 50 year warranty and quoted 150+ year lifespan. The house will probably be long gone before the loop would go bad.