Definition
A hot spot is localized overheating in a PV cell, occurring when a partially shaded or damaged cell reverse-biases under the full string current. Bypass diodes mitigate; cracked cells without functioning bypass can cause fire.
Key Takeaways
- Hot spot = localized cell overheating from shading + reverse bias.
- Bypass diodes mitigate but failed diodes risk fire.
- Detected via IR thermography.
- Long-term hot spots damage encapsulant and cell.
- Inspect quarterly on utility plants.
Frequently Asked Questions
2 commonly searched questions about Hot Spot.
What causes hot spots?
Partial shading, cell microcracks, soldering defects, broken bypass diode. Shaded cell forced into reverse bias dissipates string current as heat.
How are hot spots detected?
IR thermography during operation reveals cells 20+°C hotter than surrounding. Quarterly inspection on utility plants; opportunistic on residential.
Need engineering-backed solar designs?
Heaven Designs delivers PE-stamped solar design packages, structural calculations, electrical engineering, and utility-compliant permit plans.
