Possible Choices of the Final State of the Process Used to Determine the Maximum Output:
*	Isentropic Process (Adiabatic Reversible). The final state of the system is usually different from that of the actual final state.
*	Reversible Process with the same initial and final states as the actual operating system.
*	Reversible Process with a specifically desired final state such as the dead state of the environment.

Heat Engines:

Example: A heat engine takes in 480 kJ of heat energy at 560 K from a large heat reservoir and exhausts 190 kJ of heat into the environment at 290 K. Determine the second law effectiveness of this heat engine.

Although the actual thermal efficiency of this heat engine is low at 39.6%, its effectiveness is actually quite high at 82.1%.