Vaughn wrote:

I live in sunny south Florida, but I'm still waiting for the day that I
see full manufacturer's rated power output from a solar panel. For that
to happen, you would theoretically need a perfectly clean panel pointed
directly at a full sun, at some specific temperature, and connected to a
specific load that perfectly matches the panel's impedance. ...And
probably not even then!

There's your problem - a cloudless sky.

My solar panels put out considerably more power when the sun shines
through broken cumulus cloud.

There's actually a lot more light available in that situation (direct
sunlight plus reflection from sunlit cloud).

John