Cover of English mechanical engineer John Bryant's 2009 book Thermoeconomics: a Thermodynamic Approach to Economics. 
In thermodynamics, thermoeconomics is duel-meaning term originally defined as use of the science of economics in the improvement and study of the cost efficiencies of thermodynamical processes, but more recently meaning the use of the science of thermodynamics in the study of economies.
Etymology The term "thermoeconomics" was coined by American engineer Myron Tribus and used in a functional sense in relation to cost and efficency as presented in a 1962 paper that dealt with seawater desalination processes.  The term soon began to be used, essentially within the field of engineering, as the study of the efficency of energy use in industrial processes or as the "field that links economic analysis with thermodynamics". 
In 1990, German theoretical ecologist Bengt Mansson was using the term "thermoeconomics" in the two cultures sense of the term.
In 2001, social scientist Peter Corning began using the term thermoeconomics, in a functional sense, as the study of economic systems through the tools of energy and entropy.  Life, according to Corning, is a contingent and labor-intensive activity" in which "energetic profitability is essential to growth and reproduction". Corning calls this the first law of thermoeconomics.
In 2007, similar to Corning, American chemical engineer Libb Thims defined "thermoeconomics" as that overarching human thermodynamics discipline, developed by those such as Frederick Soddy (1922), Nicholas Georgescu-Roegen (1971), Philip Mirowski (1989), and Jing Chen (2005), and others, that thermodynamically studies human societies from an economic point of view. 
References 1. Yehia M. El-Sayed (2003). The Thermoeconomics of Energy Conversions (pg. 4). Pergamon. 2. (a) Sieniutycz, Stanislaw; Salamon, Peter (1990). Finite-Time Thermodynamics and Thermoeconomics (pg vii, 1). Taylor & Francis. (b) Berry, R.S., Salamon, P. and Heal, G. (1978). "On a Relation between Thermodynamic and economic optima", Resources and Energy, 1, 125. (c) Sieniutycz, S. (1978). Optimization in Process Engineering. Warsaw: WNT. (d) Mansson, B.A.G. (1985). Contributions to Physical Resource Theory, Chalmers University of Technology, Goteborg. 3. Corning, Peter A. (2001). "Thermoeconomics - Beyond the Second Law" (PDF), Institute for the Study of Complex Systems. 4. (a) Thims, Libb. (2007). Human Chemistry (Volume One), (preview). pg. 53, Morrisville, NC: LuLu. (b) Thims, Libb. (2007). Human Chemistry (Volume Two), (preview), pg. 677-678. Morrisville, NC: LuLu. 5. Bryant, John (2009). Thermoeconomics: A Thermodynamic Approach to Economics. VOCAT International Ltd. 6. Mansson, Bengt. (1990). “Thermodynamics and Economics”, in: Mansoori, G.A., Sieniutycz, S. and Salamon, P. (1990). Advances in Thermodynamics, Vol. IV: Finite-Time Thermodynamics and Thermoeconomics (pgs. 153-74). Taylor & Francis.