On sustainable PV-solar exploitation: an emergy analysis

Emergy analysis (EMA) is a thermodynamic-based method used for the assessment of systemic sustainability, based on the upstream energy investment necessary for creating a product or a service. Emergy, defined as the available energy used up directly or indirectly to make the product or service at issue, is the common quantity in which all the resource flows are converted. The EMA is carried out through the determination of a systemic diagram, for which all the stocks and flows are quantified by means of an exhaustive resource inventory, including human labor and services. A set of emergy-based indicators may be then calculated to assess the various aspects of the sustainability of the system. In this contribution, the principles of EMA are introduced, and its application is outlined in the case of photovoltaic technology.