Yeah, that’s the one. Economics of this are hard - but money is numbers in computers, it’s just a question of how serious the government is with getting it done - physics-wise it gets like 10-15C warmer with every km, which is important for the delta T obviously. I know nothing about drilling the extra couple km, though, only assuming it can be done with enough engineering.

I understood that temperature wasn't the problem. How it works is that you pump water into one well, and get it out from an adjacent one. The main problem was permeability, they couldn't get the necessary flow rate between the wells.