Hi,
I would venture a guess of about 50 watts of output from a 500 watt array at solar noon in moderate rain. That would depend on the choice of panel and the type of cell. I get about 36 watts from 256 watts of Uni-solar panels in moderate rain.
In perfect solar conditions a 500 watt panel may only output about 450 watts.
50 watts doesn't sound like much--but it is enough to cover parasitic loads and do a smidgen of charging too.
With a properly sized battery bank and enough watts of panels a residential fridge can be run.
