Hotspot Prevention in Solar Panels

May 18, 2022

What are Hot Spots? 

When a solar panel cell becomes obstructed by shade or debris, it can start to act as a resistor within the module's series connection, hindering current flow and reducing the energy output of the entire string. Manufacturers attempt to mitigate this by integrating bypass diodes, which redirect current around the obstructed cell. However, diodes are not a failproof solution.

In scenarios where a diode is absent or malfunctions, the affected cell begins consuming energy, drawing power from adjacent cells and creating a "reverse bias" effect. This leads to overheating and the formation of hotspots, which can significantly impact your system's efficiency and longevity.

Hotspots are not always visible but can lead to reduced power output, potential glass breakage, sheet melting beneath the panels, cell degradation, and in severe cases, fire. They are commonly detected through thermography, which isn’t always accessible to every solar panel owner, making regular performance monitoring crucial.

Common Causes of Hotspots and How to Prevent Them:

1. Shading

Obstructions like trees and buildings can cast shadows, causing hotspots. Identifying potential shading issues before installation is key. For unavoidable shade, smart electronics at the module level can optimize performance.

2. Soiling

Accumulated dirt, dust, and bird droppings can obstruct cells. Regular cleaning every two weeks is essential to maintain panel efficiency and prevent hotspot formation.

3. Physical Damage

Transport and installation mishaps can cause micro-cracks or damage, leading to hotspots. Investing in panels designed with hotspot mitigation technology, such as bypass diodes, is advisable.

4. Adverse Weather Conditions

Solar panels face threats from extreme weather like hail or lightning, which can damage panels and contribute to hotspots. Selecting panels tested for resilience against such conditions is crucial.

5. Ensure Proper Ventilation

Overheating can exacerbate hotspot risks. Ensuring adequate airflow around and beneath panels helps reduce temperature and prevent hotspots.

In closing, understanding the causes and prevention of hotspots in solar panels is essential for maintaining their efficiency and longevity. Regular monitoring, cleaning, and the use of smart technologies can significantly reduce the risk of hotspots, safeguarding your investment in renewable energy.