The ENERGEOTER 2013 project’s research activities initially focused on more purely geological topics, starting with a census of the geothermal fields present in Italy and the study of some particularly promising areas, the development of a geothermal database, and the verification of the possibilities of using sophisticated geophysical technologies such as 4D time-lapse seismics and its potential as a monitoring tool.
With regard to seismicity in geothermal fields, research activities examined European and non-European experience with the injection and/or extraction of endogenous fluids and the testing of EGS-enhanced geothermal systems.
On the modeling front, work continued on modifying and updating the GeoSIAM modeling analysis system to make it capable of representing the complex geological and structural realities of geothermal reservoirs and the complex fluid dynamic phenomena as a function of thermodynamic conditions, fluid characteristics and their phases. The improvements made to GeoSIAM were tested and validated by carrying out specific full-scale domain and multi-borehole configuration tests.
From a plant engineering point of view, the state of the art of ORC cycles was evaluated, which, thanks to special working fluids, are able to exploit significantly lower temperatures than traditional water-steam cycles. These systems represent a reliable technology already applied in various sectors such as biomass and heat recovery, but which must be adapted to the individual characteristics of each geothermal system in order to optimize its performance. Activities focused on medium enthalpy geothermal applications at temperatures in the order of 140-150°C.