Bitcoins and Energy Use 

One day, the final bitcoin will be mined, since there are a finite number of them. Will that be the end?

On that day, in that country, scorched by drought, swept clean by tornados and floods, burnt dry by wildfires, starved by the consequent soil destruction, and overrun by internal and external climate refugees,  a new crypto currency will be proposed and implemented, resistant to quantum calculations, that will burn up the remaining fossil fuel.