Thermodynamics and its value as an energy policy tool

Of all the fundamental physical considerations that enter into the determination of personal and collective energy policy, only one can be quantitatively addressed through thermodynamics: this is the minimal use of energy resources to achieve conservation of scarce energy supplies. Thermal efficiency (redefined in this work as effectiveness coefficient) has been widely used in evaluating energy exchanges, but this procedure gives no consideration to quality of energy being used. Thermodynamics indicates that different energy quantities also can have different energy quality and efficient use of energy requires a matching of the energy quality supplied to that required for the given task. Thermodynamic efficiency as a “figure of merit” in evaluating energy exchanges has the advantage of considering energy quality. It does not, however, give information to assist in the trade-offs between energy resources and the other considerations that must be made in the formulation of an energy policy.