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How to Calculate Carnot Efficiency

What is Carnot Efficiency?

Carnot efficiency is the theoretical maximum efficiency of a heat engine operating between two temperature reservoirs. No real engine can exceed this limit.

Formula

The calculator applies η = 1 - (T_cold / T_hot)

Step-by-Step Guide

  1. 1Enter hot reservoir temperature (T_hot) and cold reservoir temperature (T_cold)
  2. 2The calculator applies η = 1 - (T_cold / T_hot)
  3. 3Results show maximum theoretical efficiency

Worked Examples

Input
T_hot = 600 K, T_cold = 300 K
Result
η_max = 50%
Best possible performance

Common Mistakes to Avoid

  • Using Celsius instead of Kelvin temperatures
  • Assuming actual engines approach Carnot efficiency

Frequently Asked Questions

Why can't we achieve Carnot efficiency in real engines?

Real engines have friction, heat losses, and irreversible processes that reduce efficiency below the theoretical maximum.

Does Carnot efficiency depend on the working fluid?

No, Carnot efficiency depends only on the two reservoir temperatures, not on the engine type or working substance.

Ready to calculate? Try the free Carnot Efficiency Calculator

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