And how long will it take us to boil of the oceans (as in fusion) assuming 5% year over year increase?

How has energy consumption behaved before around the time of paradigm shifts and plentiful "free" energy?

Currently energy use is about 0.01% of energy that the sun sends us (if my googling is right). If energy use increases 5% per year, it doubles every 15 years or so, so after a hundred years we still use so little energy that it doesn't matter compared to solar heating. I think the oceans are safe.

And I'm all in favor of fission as a bridge-fuel to something more sustainable, but many people act as though it will last indefinitely, when it seems clear to me that it won't.