Solar Panel Temperature Derating Calculator
Estimate the temperature-related power adjustment relative to a reference temperature for a photovoltaic array.
How to use this calculator
- Enter rated dc panel power (kw), estimated cell temperature (°c), power coefficient (% per °c above reference) and the remaining stated inputs; keep their units consistent.
- Review the result and intermediate values; change one input at a time when comparing scenarios.
- Keep the stated formula and assumptions with any result you share.
Formula and method
Adjusted power ≈ rated power × [1 − coefficient × (cell temperature − reference temperature) ÷ 100].
- The temperature-adjusted estimate is about 4.9225 kW.
- This is only a temperature adjustment. Irradiance, shading, inverter limits, wiring, soiling and other losses are not included.
Worked examples
Worked example
5.5 kW rated power, 55°C cell temperature and a 0.35%/°C coefficient referenced to 25°C.
The temperature-adjusted estimate is about 4.9225 kW.
The temperature-adjusted estimate is about 4.9225 kW.
Understanding the result
The temperature-adjusted estimate is about 4.9225 kW.
This is only a temperature adjustment. Irradiance, shading, inverter limits, wiring, soiling and other losses are not included.
Important notes
This is only a temperature adjustment. Irradiance, shading, inverter limits, wiring, soiling and other losses are not included.
Use measured inputs and verify that the model matches the situation before making an operational, financial or technical decision.
Frequently asked questions
Can cold panels produce above rated power in this model?
Yes, the coefficient formula may predict an uplift below the reference temperature. Other limits can still cap actual output.
Where do I get the coefficient?
Use the panel datasheet coefficient and verify whether it specifies power, voltage or another parameter.
What should I check before relying on this result?
Verify units, input definitions and assumptions against your real data or the relevant product, service or professional guidance.
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Related explanations
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This page provides a calculation tool plus explanatory information so you can understand what the result means and when the underlying method may not fit your situation.