> The drop off after cleaning could well be because some of the initial boost could come from the water cooling off the panels: solar panels become less efficie

> The drop off after cleaning could well be because some of the initial boost could come from the water cooling off the panels: solar panels become less efficient at higher temperatures so the drop of after they're all cleaned could be them warming up again after the water has evaporated. This was almost certainly the case. AIUI, that cooling still makes a large difference. Makes me wonder if it is worth it having a small esp32 or similar control a sprinkler system for the panels. Keep them cool during high ambient temps by spraying a litre of water on each panel every 30m. An idea I had a while back (when I was considering panels) was running my mains water through the back of each panel (before the mains got to the hose) in a sort of radiator pattern.