Are internal combustion engines subject to the limits of the second law of thermodynamics?

The statement that internal combustion engines are not subject to the limits of the second law of thermodynamics is not accurate. In fact, internal combustion engines operate under the constraints imposed by this fundamental law of thermodynamics, which states that energy systems tend to evolve toward a state of maximum entropy, or disorder.

Internal combustion engines convert the chemical energy from fuel into mechanical energy. However, not all of the energy from the fuel can be converted into useful work; some of it is always lost as waste heat due to inefficiencies inherent in the process, as dictated by the second law. This law implies that no engine can be 100% efficient and that some energy will always be unavailable for doing work, therefore, internal combustion engines are indeed subject to the limits of this law.

Understanding this principle is essential for recognizing the challenges in improving the efficiency of these engines as we attempt to design systems that produce less waste and reduce their environmental impact.