I placed one solar panel in a polluted chunck and another with no pollution at all.
Both have the same power output.
The 2nd solar panel does not supposed have more power output ?

Individual solar panels of the same type/kind cannot have different power outputs. But, there is a per-surface/planet modifier that can adjust the effectiveness of solar power. So, each solar panel's effectiveness is adjusted based on its individual characteristics, but this is aggregated into one single modifier that affects all panels. The end result is the same, but you won't notice differences between individual panels' tooltips.

Oh right, I see! I don't have to worry about that then, thanks. :)

Sorry, my English isn't very good, so I'm using a translator.
I'm not smart, so I don't quite understand what you're saying.

The power output tooltips for each solar panel placed in a polluted chunk and a clean chunk are displayed identically.
So, are you saying that only the tooltips display the same output, and that the solar panels in the clean chunks output power normally?

The only important thing to know is that the math is correct. For example, both of these situations produce the same result:

• 1x at 100% and 1x at 0% = 60kW
• 2x at 50% = 60kW

You may already know that Solar Panels in Factorio are the friendliest for UPS, because they all work the same - they are grouped together into a single result. So, we cannot tweak each panel; we can tweak the grouped panel's output.

I understand :)
Thank you for the explanation!