How much power do solar panels lose in heat?

Most panels lose 0.3–0.5% per °C above 25°C (STC). At 60°C cell temperature (common on hot days), a 400W panel produces only 330–358W — a 10–17% reduction.

What is the difference between STC and NOCT?

STC (Standard Test Conditions) uses 25°C, 1000 W/m². NOCT (Normal Operating Cell Temperature) reflects real-world conditions at 800 W/m², 20°C ambient. NOCT output is typically 85–92% of STC.

Which panels handle heat better?

N-type TOPCon and HJT panels have temperature coefficients of -0.26 to -0.30%/°C, outperforming standard PERC panels at -0.35 to -0.40%/°C in hot climates.

Solar Panel Temperature Derating Calculator

Calculate how high operating temperatures reduce solar panel power output. Uses panel temperature coefficient (Pmax) to find actual power vs STC rating.

2D stress state at a point. All stresses in MPa.

σx — Normal Stress X (MPa)

σy — Normal Stress Y (MPa)

τxy — Shear Stress (MPa)

⚙ Mechanical Note: Results are based on standard textbook formulas and ISO/AASHTO references. Always verify critical designs with applicable codes (ISO 898, AASHTO 1993, AISC, Eurocode 3) and a qualified engineer.

How to Use

Enter the values for the patient or scenario you are assessing. Calculate how high operating temperatures reduce solar panel power output. Uses panel temperature coefficient (Pmax) to find actual power vs STC rating. Use the solar temp derating result to inform your clinical assessment.

Related Calculators

Solar kWh/Day

Energy & Utilities

Solar Tilt Irradiance

Energy & Utilities

Solar Payback

Energy & Utilities

Solar Panel Temperature Derating Calculator

How to Use

Related Calculators

Frequently Asked Questions

How much power do solar panels lose in heat?

What is the difference between STC and NOCT?

Which panels handle heat better?