From what I understand the whole point of the solution is that you don’t have to remove their equivalent of a drill string while drilling the whole. It can all

From what I understand the whole point of the solution is that you don’t have to remove their equivalent of a drill string while drilling the whole. It can all be done in one continuous operation. That’s why it’s so much faster. I’m not sure they would need cooling down there? They’re continuously blasting gas down inside the waveguide, and the gas can only escape on the outside around the waveguide. Maybe it’ll be like blowing air down a straw into honey. I don’t know the temperature of the gas they’re pumping down, but maybe it’s colder than the rock at deeper depths which will help keep the rock around the waveguide cool expect for at the tip where the rock is being blasted. Do they need a casing? I seem to remember reading somewhere that the process of blasting the rock will harden the walls of the hole. Though I’m curious how that would work at extreme depths.