| Abstract |
Underground Thermal Energy Storage (UTES) technologies have not been widely utilized so far as it should be optimal. An important cause of this backlog is that UTES usually is not yet an independent technologic challenge or project, we regard it as part of the heat production and/or energy management. Therefore it is well worth - seeing the technology linking between UTES and the fairly developed geothermal technologies with wide experience, and also - reviewing the latest results in innovation and the development opportunities. This process can generate new way of thinking in field mamagement and we can recommend new opportunities to enlarge the utilization of this type of energy storage. The presentation follows this process and sets up middle-term UTES projection in Hungary. The first approach in the status review of UTES is the development of the evaluation of geological background. Geological exploration have developed significantly in the latest decade, it provides better opportunities for underground heat storage than before. The national and international databases, as well as new geological concepts help to evaluate precisely the heat storage potential of the different formations. The second approach is the systematization of the available technological solutions of producing and reinjection of fluids, as well as the creation of underground heat exchangers. The shallow (with maximum 300 meter deep wells) and deep storage (with over 300 meter deep wells) are to be evaluated separately, because of the different technologic challenges. Shallow utilization have experience with ground source heat pumps, but deep UTES needs a lot of research and further deep demonstration projects are to be planned. The third approach is focusing on the heat market on the surface. Different technology and energy solutions are needed in every project. UTES projects wish to exploit synergies of energy and geothermal industry, as well as make renewable energy projects more competitive. Moreover, hybrid solutions increase the renewable energy capacities efficiently and improve the flexibility of the utilization of renewable energies. The geothermal energy industry already has more and more experience so UTES has to find it long term positions. The presentation reviews all the three approaches (geological exploration, available technologies and heat market issues), makes a distinction between shallow and deep UTES opportunities and provides recommendation to widen the utilization of UTES in the geothermal sector. A middle term projection is presented with taking into consideration the real Hungarian geological, legal, economic and technological background. |