Current world power consumption is about 15 terawatts. That's 15,000 gigawatts. [0] One gigawatt takes about 1 nuke. So, 15,000 nukes. Round that down to 10,000 nukes; ignore demand from new electric cars and cooling, and required downtime.

On a very good day, a new nuke rounds down to $10 billion. 10^4 x 10^10 = $ 100 trillion. Not to mention mining, operating, disposal, and environmental costs. Or tsunamis, or profits, or interest.

In other units (Q = 10^18 joules) Total world energy consumption per year: 400 Q. Total solar power striking the Earth each year: more than 4 x 10^6 Q.[1] Catch 1/10,000 of that.

[0] https://science.howstuffworks.com/environmental/green-scienc...

[1] http://sites.science.oregonstate.edu/~hetheriw/energy/topics...

But isn't one of the problems of global warming (ie where humans have a "future") the amount of waste heat we are producing?

https://environmentalsystemsresearch.springeropen.com/articl...