06/03/2026
“Dirty rain” (rain mixed with dust, pollution, or mud) can have negative effects on solar panels, mainly because it leaves residue on the surface instead of cleaning it. Here are the main effects ☀️🌧️:
1. Dirt Residue Reduces Sunlight
Dirty rain can leave a thin layer of dust or mud on the glass surface of solar panels.
* This layer blocks part of the sunlight from reaching the photovoltaic cells.
* Even a small amount of dirt can reduce output by 5–25%, depending on how thick the residue is.
2. Formation of Sticky Deposits
If rain contains industrial pollution or fine particles, it may dry and form sticky spots.
* These spots attract more dust over time.
* The panel becomes harder to clean naturally with later rainfall.
3. Uneven Shading (Hot Spot Risk)
When dirty rain leaves patchy dirt patterns, parts of the panel receive less sunlight.
* Uneven sunlight can create “hot spots”, where some cells heat up more than others.
* This can slightly reduce efficiency and, in rare cases, stress the panel.
