Please. I know lots of folks here live in Silicon Valley and are breastfed with this kind of fantasy, but making our species multi-planetary isn't just a matter of energy availability.

Plus, and most importantly, trashing our one and only planet "because we are not bound to it" is just one of the most unethical and most dangerous plan one can think of. And I know that there are plans to become a multi-planetary species without making Earth inhabitable in the first place, but I think the quote "Everyone has a plan until they get punched in the face" applies beautifully here. And the fist of climate change combined with biological collapse will hurt badly.