What does exhaust loss mean?

Exhaust loss refers to the energy lost as heat in the exhaust gases produced during combustion in engines, such as those in vehicles or power plants. This energy, which is not converted into useful work, represents a significant efficiency loss, as it contributes to the overall energy waste in the system. Reducing exhaust loss can improve engine efficiency and performance, often achieved through design improvements or technologies like turbocharging and exhaust heat recovery systems.