A hot spot is a phenomenon that occurs in a solar panel when one or more cells are shaded and the heat generated there can damage the panel while reducing its performance. It is one of the most common problems that can negatively affect the efficiency and lifespan of solar systems in the long term.
How does a hot spot form?
Shading : Shade, dust, dirt, or leaves can partially obscure the solar panel cells.
Decreased power output: Shielded cells do not produce enough power, while unshielded cells continue to operate at full capacity.
Voltage difference: Due to the difference, the shaded cells start to act as a resistor and the system tries to equalize the voltage generated on these cells.
Heat generation: Shielded cells can overheat, leading to heat generation, i.e. the formation of hot spots.
Effects of hot spots
Cell damage: Overheating can destroy the affected cells, which will no longer be able to produce electricity efficiently.
Efficiency loss: The performance of the panel can be significantly reduced as the affected cells negatively affect the operation of the entire panel.
Shortened lifespan: Heat damage can permanently reduce the lifespan of a solar panel.
Safety risk: In extreme cases, excessive heat generation from the hot spot can cause a fire.
Hot spot and system efficiency
| Status | Impact on performance |
|---|---|
| Shadowless panel | Maximum efficiency (100%) |
| Minor shading | Performance loss (5–20%) |
| Severe shading | Significant decrease and hot spot formation |
Summary
Hot spots are a common problem that can cause significant damage to solar panels if not addressed in a timely manner. Proper installation practices, maintenance, and the use of bypass diodes can help minimize the chance of hot spots developing. Avoiding shaded areas and performing regular inspections can help maintain the efficiency and lifespan of your solar system in the long term.