Thermoeconomics has been developed with the main object of first identifying, and then reducing the costs of the energy produced by industrial power plants. More recently, the same approach formalized in the Exergy Cost Theory has been recognized as a useful tool also in a wider field, like industrial symbiosis and sustainability assesment. To do this, exergy supply chains have been tracked backward and backward, to include in the primary resource consumption a more and more complete inventory of the indirect consumption. In Authors' opinion, the future of Thermoeconomics is to go on in this directions. If a very complete inventory of all indirect consumption were obtained, the sustainability assessment of a production process could be performed (at least in principle) by applying the idea that the lower its consumption (direct and indirect) of scarce primary resources, the more sustainable a production process is. In this paper, the idea of the Thermoeconomic Environment (TEE) is summarized, to highlight as it is a consistent ultimate boundary of the exergy cost accounting, where the origin of the exergy supply chains can be properly placed. Then, the frame of the TEE is used to discuss some possible options for obtaining a more complete inventory of all indirect consumption, and to outline possible perspective connections with some relevant environmental models, coming from Biology, Dynamic of Populations, or Climatology.
