Exergy: A better way of looking at energy systems

The law of conservation of energy, stating that energy cannot be created nor destroyed, is inadequate to measure the performance of energy systems in the built environment: Even though energy figures suggest differently, these systems generally present a very poor performance, as they achieve only a fraction what is theoretically possible. By looking at exergy a much more meaningful insight into
the performance of energy systems is obtained, which can greatly support the development of energy systems with a reduced need for high quality energy.