# What is meant by Carnot efficiency?

## What is meant by Carnot efficiency?

Carnot efficiency is the maximum efficiency that a heat engine may have operating between the two temperatures (Figure 2-7). The Carnot efficiency has little practical value. It is a maximum theoretical efficiency of a hypothetical engine.

What is the difference between thermal efficiency and Carnot efficiency?

Carnot efficiency represents the maximum possible efficiency which can be obtained by a given thermodynamic cycle. It is calculated based strictly on the maximum and minimum temperatures which occur in the cycle. Broadly speaking, thermal efficiency represents the ratio of work energy output to energy input.

### What is the efficiency of Carnot engine in terms of temperature?

It is well known that the Carnot cycle efficiency ( η thermal = 1 − T L T H ) is maximized with the highest possible heat source temperature TH and the lowest possible heat sink temperature TL.

Why the efficiency of a Carnot engine only depends on the temperatures of the hot and cold reservoir?

The efficiency of a Carnot engine depends solely on the temperatures of the hot and cold reservoirs. Carnot’s theorem states that all heat engines between two heat reservoirs are less efficient than a Carnot heat engine operating between the same reservoirs.

#### What is Carnot efficiency-efficiency of Carnot heat engine?

What is Carnot Efficiency – Efficiency of Carnot Heat Engine – Definition. Carnot Efficiency or Efficiency of Carnot Heat Engine. is an idealized efficiency. It is valid only for reversible processes and depends only on temperature difference between reservoirs. Thermal Engineering.

How is a reversible heat engine different from a Carnot cycle?

The reversible heat engine works on a reverse cycle and behaves as a heat pump. The Carnot cycle is reversible signifying the upper limit on the efficiency of an engine cycle. Practical engine cycles are irreversible and therefore have inherently much lower efficiency than the Carnot efficiency when working at similar temperatures.

## What is the coefficient of performance of a Carnot refrigerator?

We have just found equations representing the efficiency of a Carnot engine and the coefficient of performance of a Carnot refrigerator or a Carnot heat pump, assuming an ideal gas for the working substance in both devices. However, these equations are more general than their derivations imply.

Why are fuel cells not Carnot efficiency limited?

Therefore, the important point about fuel cells is not that they are not Carnot efficiency limited, rather they are (i) free from incomplete reaction or product dissociation because of the much lower operating temperatures; (ii) free from the high temperature limit imposed by materials on any heat engines and (iii)…