Direct uses of geothermal energy in Italy 2005-2009: update report and perspectives

Italy is widely known for the strong expertise in field of geothermal electricity production. Despite the presence of such industrial know how, previous analysis reveal a huge untapped potential in geothermal direct uses. This paper, based on qualitative and quantitative information and expert evaluations, aims at giving an overview of market achievements in the last five years. The situation of direct uses of geothermal heat in Italy, compared with the situation of 2005, appears widely evolved and is rapidly moving to reach significant targets set for 2010. The global growth of direct use of geothermal heat at the end of 2009 in Italy is expected to reach an amount of 1.2 times more than the values of the previous update: 850 MWth and 10,000 TJ compared to UGI-2006 values of 650 MWth and 8000 TJ. This larger contribution, in terms of installed power, is mainly due to the wide development, principally in northern areas of Italy, of geothermal district heating (5-15 MWth unit power) and, in terms of numbers of installations, to single household applications, which are widely applying heating & cooling equipment with geothermal source of small unit power. Analyzing the heating and cooling systems in civil buildings, and in particular the ones that use middle depth or shallow geothermal resources, a relevant impulse to the growth of geothermal industry has certainly been obtained by the large increase of geothermal heat pumps systems, fed by ground heat with horizontal or vertical exchanger, or by hot water extracted with shallow depth wells both in open or closed loops. At the moment, the number of companies which provide HPGS in Italy is growing very fast and thus, in the near future, a continuous growth of the geothermal direct uses is foreseen. The market development is driven by challenging applications as the ones, characterized by a high level of technology integration, in progress in Grado (Udine) and Milan. In the past five years, the geothermal direct uses reached a greater interest than in the past also from the designers' community. Hence, as a consequence of the market dynamics, the unitary cost of the geothermal installations is decreasing and, at the same time, the need of new and specific regulations, both regarding performance and environmental preservation, is increasing. The lack of shared databases of authorized plants and of shared rules for their classification represents the main barrier for further research. For this reason, new investigation and acquisition of detailed multidisciplinary information are required so as to support the development of public policies and private strategies.