Except you aren't leaving that heat in place.

You're concentrating it into a very small area of compute.

If you don't spread that heat back out, it's going to find a much higher thermal equilibrium than the solar panels themselves would find just absorbing the sunlight and radiating the energy back into space.

It's like you've pointed a magnifying glass at your compute, except with electricity, which means you can reach temperatures higher than you can with a magnifying glass.