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There is a growing need for the analysis of energy systems not only on the bases of their operational life, but also on the basis of considerations for the manufacturing and recycling phases. Environmental and to a lesser extent resource scarcity factors sould also be taken into consideration. A general unified thermodynamic approach based on exergy was recently proposed [1,2,3] and is briefly summarized. The main idea of this approach is to minimize the cumulated exergetic losses of operation, manufacture and recycling distributing the exergy of manufactrue (the so-called gray exergy) and recycling over the life time of the system. Additional levels of analysis consist of introducing pollution and resource scarcity factors and using these to artificially penalize the above mentioned exergy terms. In this paper, the first level of analysis (exergy analysis with gray exergy) is applied to four domestic heat pumps operating with different evaporators (direct expansion horizontal ground coil, brine horizontal ground coil, brine geothermal U tubes and air-source).