Also, think of a battery with no internal resistance , the current it puts out doesn’t heat it. (It also doesn’t cool it, the energy comes from a chemical change.)

Bob

 

Also, think of a battery with no internal resistance , the current it puts out doesn’t heat it. (It also doesn’t cool it, the energy comes from a chemical change.)

Bob

out of interest

where does this leave the OP ?

 

out of interest

where does this leave the OP ?

The original premise was wrong - connecting a load cools the panel down. The reduction in temperature rise could be as smush as 20% ( or whatever the panel efficiency is)
And my simplistic SPICE model was closer to the truth than I realised.
As efficiency drops as temperature increases, the higher the load, the cooler it will run and the more efficient it will get.