In large parts of the world (e.g. where I live, in Texas, USA) this is by far when the largest electricity usage is (because it's when the air conditioners are

In large parts of the world (e.g. where I live, in Texas, USA) this is by far when the largest electricity usage is (because it's when the air conditioners are working hardest). So, yes we will have to have some non-solar energy, we could get to much larger than we already are (and it's growing fast) because that is when the peak usage is.