The intense heat energy beneath the Earth's crust is virtually limitless, but for most of history geothermal had always been an underrated and ignored power source mainly due to location problems (you have to build them next to volcanoes). And drilling of course becomes more expensive the more you dig deeper due to the bits wearing out while the rock becomes more dense. But "deep geothermal" technologies like Quaise millimeter-wave or Plasmabit plan to use direct-energy drilling to melt/vitrify this highly dense rock and dig deeper than ever before, potentially reaching such depths in the Earth where the heat is so intense it can turn water/steam into a supercritical state. This in theory can make geothermal available all over the world.
But I'm rather sceptical. You can dig that deep, but with the kilometer-long pipes needed, won't the supercritical water lose a lot of its energy as it comes back to the surface?
https://www.youtube.com/watch?v=Q2kRzKEJW4o
https://www.youtube.com/watch?v=cacaUwrIrkY