I'm shocked that they'd choose the 3M liquid (Novec 7000 Engineered Fluid, 1-methoxyheptafluoropropane). It is at least 100 times more expensive than using a light oil. And even that is far more expensive than if they reduced the physical packing density of the miners and air cooled them like in any conventional datacenter with ambient/evaporative cooling. So I'm surprised to see them claim that their reduce floor space (and saving on rent) is the more economical option. Especially since the entire 'mine' will be irrelevantly inefficient within 12 months and won't be worth the electricity bill. Good for them though, the rest of us can only dream of having that kind of capital.