Update of heat flow data in the geothermal areas of Tuscany, Italy

Tuscany is the region of Italy where geothermal energy production started, first in the world, in the early years of 20th century. With an installed capacity of 915 MW, today the totality of Italian geothermal electricity production is concentrated in Tuscany, in the well-known high enthalpy fields of Larderello-Travale and Mount Amiata, owned and managed by ENEL (National Electricity Board). A Legislative Decree of 2010 liberalized the geothermal market, allowing new operators to request exploration leases. As of today, 24 new research permits are active in Tuscany, all of them in the surrounding areas of the two main geothermal fields. The foreseen target of the exploration should be a geothermal resource sufficient at least to allow the construction of binary technology power stations (or better, depending on the quality of the resource). A huge amount of exploration and production data exist in the geothermal areas, and new campaigns have been planned or already started to acquire site-specific information in the new research permits. We present the results of heat flow (HF) measurements carried out in new 200-250 m gradient wells drilled in areas West of Mount Amiata, and regional HF and geothermal gradient maps updated by gathering all well thermal data that became recently available. A comparison with different parameters (e.g. Bouguer gravity anomaly) allows a better definition of the geothermal features of the new areas of exploration.