A Wild,speculative long-term tip with much promise, page-9

As I understand it, it will be hot water that will be coming to surface, not steam. The rock temp is 250c so I expect a bit of cooling as it comes up the drill hole should not be problematic.

They then use heat exchangers at surface to transfer energy for electricity generation.

With regards to water - some water will be required to saturate the country rock in the fractures around the drill holes but being granite cant see that this would require a major volume of water.

acturtle