[skyzadev]

So you are saying we will capture so much energy from the sun that the entire planet will become inhospitable. Do we then just keep burning fossil fuels until earth becomes inhospitable instead? Or do we kill ourselves and stop the need for energy use entirely? Remember that humans will forever have energy needs as we advance.

[paulmd]

Absolutely yes, at a sufficiently big-picture view the eventual problem is energy expenditure itself. Capturing more energy from the sun, or more realistically something like large-scale fission/fusion utilization still results in an increased amount of energy being deposited into the earth's atmosphere even aside from the greenhouse effect.

I am obviously not an expert but I looked at the magnitude of the energy itself vs the greenhouse effect and it's about 10-100x less potent than the greenhouse effect. But that means that even if we had 100% clean carbon-free energy, we can't continue increasing our energy utilization forever. And we still have a huge portion of the world that is below a first-world living standard and will eventually want automobiles and air conditioning and vacations using jet travel too.

IF we do not level off the energy consumption of the "first world" standard of living sometime within the next 50-100 years then we are on a course to cook ourselves to death even with 100% clean energy.

[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.

[faeyanpiraat]

The point is that nothing is as simple as it seems. Using a renewable sources has their own side effects.

Solar? It heats the atmosphere, because it captures solar heat which would bounce back.

Wind? Obviously it slows winds down, and who knows how it affects the existing ecosystem. We know how important the gulf stream is, you wouldn’t want to slow that down..

Etc..