Geothermal will not be as cheap as solar, so if we use a lot more power, it will mostly be solar. (Geothermal would be used mainly for baseline, at night.)

Solar intercepts energy already arriving, to use before it is then re-radiated to space. It arrives regardless.

So, no problem. What we have now is a catastrophically big unfolding climate crisis. Even if there were a problem, any small problem is a wonderful substitute for a catastrophically big problem.