I have always wondered why we did not resort more to geothermal energy, you dig deep enough and you find constant heat. No need for any fancy contraptions, exotic semi conductors or rare earth metals. You get +25°C per kilometer of depth. Can be done about anywhere on the planet except in mountainous areas.
The soviets dug a 12,262 meters deep hole back in the day, temperature at the bottom is 180°C. What kind of advantages nuclear fission plants can have over that..since they use the fission heat to run steam turbines anyway ?
By the by, what is causing the earth's core to be melted..fusion maybe ??? See Fusion at the center of the earth from Nature ( 2016).
Kind of remind me of that metallic hydrogen they made using... a high pressure anvil.....