1 Feasibility study (I stage) of CO 2 geological storage by ECBM techniques in the Sulcis coal province (SW Sardinia, Italy) Fedora Quattrocchi 1 , Roberto Bencini 2 , Carlo Amorino 3 , Roberto Basili 1 Giorgio Caddeo 4 , Barbara Cantucci 1 , Raffaele Cara 3 , Giorgio Cauli 4 Daniele Cinti 1 , Cristina Deidda 4 , Giuseppe Deriu 4 , Aurelio Fadda 4 , Marco Fadda 4 , Fandiño 2 , Stefano Faranzena 4 , Angelo Giannelli 2 , Gianfranco Galli 1 , Marco Mazzotti 5 , Stefan Ottiger 5 , Luca Pizzino 1 , Ronny Pini 5 , Giorgio Sardu 4 , Giuseppe Storti 5 , Nunzia Voltattorni 1 1 Istituto Nazionale Geofisica e Vulcanologia (INGV), Via V. Murata 605, Roma 00143, Italy, quattrocchi@inv.it 2 Independent Energy Solutions, S.r.l., Rome, Italy 3 Sotacarbo S.r.l., Carbonia, (Ca), Italy 4 Carbosulcis S.r.l., Gonnesa (Ca), Italy 5 ETH Swiss Federal Institute of Technology, Zurich, Switzerland Abstract An ECBM feasibility study started for the Sulcis Coal Province (SW Sardinia, Italy): available geochemical, structural-geology, stratigraphic and reservoir engineering considerations as well as the newly gathered experimental data are discussed, including fluid geochemistry (major and minor elements, dissolved gases, C and He isotopic ratios) of different strata/reservoir, coal composition and experimental data on CO 2 /CH 4 adsorption on coal. A MapInfo GIS structure was built up including stratigraphic, geo-structural, hydro-geochemical, coal-compositional and environmental-impact information as well as the CO 2 sources location and typology. Though preliminary, these data highlight both the positive and negative features of the Sulcis Coal Province with respect to the exploitation of the ECBM technique. CO 2 geological storage and CH 4 production potentials in Sulcis have been roughly evaluated as a whole, in the frame of the Sardinia region CO 2 sources, including the coal-fired power plants, both existent and foreseen (hundreds of millions of tonnes of CO 2 are possible to be stored underground in the next decades). The most important objective of this phase I of the project is the selection of the best Sulcis ECBM test-pilot site, which will be followed by the choice of a site for scale up (Phase II-2007) and possibly by future full scale implementation within a network type of project (Phase III-2008). Keywords: ECBM potential, Sulcis Coal Province, fluid geochemistry, coal composition Introduction The potential storage of CO 2 in Italy has never been fully evaluated [1,2,3,4] but we are convinced that a general Italian survey could be supported by running in parallel specific feasibility studies in “operative” test sites addressed to ECBM, EOR or EGR exploitation. Soon after the first encouraging scientific results (i.e. Allison Unit, USA, [5,6,7,8]) some pilot-test projects and feasibility studies have been initiated worldwide [5 and references therein]. In Italy, significant coal reserves are not present with the exception of the Sulcis Coal Province (Sardinia), which is not yet exhausted. The Sulcis region occupies the South-Western end of Sardinia. The project about which we report has the main objective to evaluate the ECBM technique exploitation throughout the Sulcis Coal Province as a whole (more than 1400 Km 2 wide totally divided in 725 Km 2 in-shore and 730 Km 2 off-shore), starting from the