Geothermal potential of Poland and the possibility of adapting the UNFC-2009 international classification of geothermal resources

The paper presents the state of knowledge on geothermal resources in Poland, which is as the result of systematic research work carried out for over the last 30 years, at the Department of Fossil Fuels (formerly the Institute of Fossil Fuels) of the AGH University of Science and Technology. The paper describes the principles of classification and methodology of regional geothermal resources assessment used in Poland, which is based on the McKelvey's diagram. The classification of geothermal resources used so far in Poland takes into account two basic factors: the degree of geological recognition and environmental, technical and economic issues concerning exploitation of geothermal water - together. The results of geothermal resources estimation are presented, taking into account particular classes of the resources: accessible, static, static-recoverable, disposable and exploitable, determining the use of geothermal waters for different purposes: heating, recreation, balneotherapy etc. The paper also presents a description of the concept of a new classification of geothermal resources (UNFC-2009), developed in 2016, within the framework of joint activity of the specialists of the European Economic Commission (UNECE) and the International Geothermal Association (IGA). The above classification is based on a three-dimensional resource classification model, where in addition to the criterion of economic viability and geological recognition, the criterion related to the project feasibility and its development is also considered. The introduction of consistent rules within the UNFC-2009 classification and the unification of the reporting method, taking into account market and economic criteria, will improve the exchange of information and may facilitate international cooperation in the field of global geothermal energy resources assessment. Guidelines for the use of UNFC-2009 were approved by the European Commission during its 22nd session in November 2013 and are available as a publication of the European Economic Commission (UNECE) (ECE Energy No. 42). The article presents three representative, operating geothermal installations in Poland, in: Podhale, Stargard and Poddebice, for which the principles of UNFC-2009 classification could be used and a case study for these selected geothermal fields could be developed.