[skyzadev]

What I am really getting out all of this is that at some point we will hit the human population limit that earth can sustain, even with renewable energy sources.

Whether or not that limit is actually reachable and something we should actually worry about I don't know. i.e: is there enough physical space for that many people on earth where each person uses X amount of renewable energy where the sum of X is greater than the amount of energy the earth can actually capture without being negatively affected.