Enter the temperature of the cold reservoir and the temperature of the hot reservoir to calculate the theoretic Carnot efficiency.

Carnot Efficiency Formula

The following equation is used to calculate the theoretical efficiency of a heat engine, otherwise known as the Carnot Efficiency.

n = (Th - Tc) / Th * 100

n = (Th – Tc) / Th * 100%

  • Where n is the Carnot efficiency
  • Th is the hot temperature (Kelvin)
  • and Tc is the cold temperature. (Kelvin)

To calculate the Carnot efficiency, subtract the cold temperature from the hot temperature, divide the result by the hot temperature, then multiply by 100.

A heat engine is a device used to capture energy or heat. During the process of heat moving from hot to cold, energy can be captured. However, this can not be done at 100% efficiency due to the laws of thermodynamics.

Carnot Efficiency Definition

In its essence, the Carnot Efficiency is the theoretical max amount of energy you can get from a heat engine with two reservoirs of different temperatures. It’s important to note that the temperatures used in this equation have to be in Kelvin. Celsius or Fahrenheit will not yield correct results.

How to calculate Carnot Efficiency?

How to calculate a Carnot efficiency?

  1. First, determine the hot temperature.

    Determine the temperature of the hotter material or area.

  2. Next, determine the lower temperature.

    Measure the temperature of the cooler material or area.

  3. Finally, calculate the Carnot efficiency.

    Using the formula above, calculate the Carnot Efficiency.


What is a Carnot Efficiency?

Carnot Efficiency is a measure of the theoretical max efficiency of the transfer of heat energy from one substance to another. This is most often used in the analysis of heat engines.

Carnot Efficiency Calculator