Temperature Coefficient

The temperature coefficient states how much power a panel loses for every degree above 25 °C, typically −0.30% to −0.40%/°C for modern modules. On a 65 °C Indian rooftop afternoon, that is a real loss of 12–16%.

This is why panels are rated at 25 °C but rarely deliver nameplate power at noon, and why ventilation gap under modules matters. Lower (better) coefficients are a genuine reason to prefer TOPCon/HJT in hot regions.

Part of the HUM Solar Glossary — 75+ plain-language definitions for India’s solar ecosystem, maintained as a neutral reference. Browse all terms →