 Thermal efficiency

The thermal efficiency of a heat engine is the net work output divided by heat input. For a cycle absorbing $Q_{\mathrm{in}}$ and rejecting the positive amount $Q_{\mathrm{out}}$,

Thermal efficiency is a measure of how effectively a system converts heat energy into useful work or energy. It is often expressed as a percentage and is calculated by comparing the useful work output to the total heat input.