Prospectives for exploiting the geothermal resources of Ikaria, Greece

Abstract

Ikaria is a small Greek island in the NE Aegean sea. Low-temperature hot springs 35-50°C are spread all over the island and especially on the eastern part near the capital Agios Kirikos. At present the springs are used only for medical purposes. According to the LINDAL diagram there is a great variety of possible geothermal applications in Ikaria, but the limited extent of this report restricts us to only two, swimming pool design and district heating simulation. The swimming pool which has been selected for Ikaria is 25×13 m2 in size, has a volume of 455 m3 and a surface area of 325 m2. The design water temperature is 30°C and the turnover period is 4 hours. The total heat demands of the hot saline water, using a titanium plate heat exchanger, is about 628 kW. The amount of geothermal water needed is about 8 kg/s (or 691 m3/day). The NovaSim District Heating Simulator was used for obtaining the most important information for a hypothetical space heating system in Ikaria. The results of this simulation indicate that the amount of geothermal water needed for heating 1000 buildings in Ikaria during the maximum heat demand season is 38 l/s (or 3283 m3/day). Regarding energy needs, the hot springs of the island are able to cover the heat demands of any low enthalpy geothermal application. But feasibility does not depend only on the availability of the energy resource but also on economic factors and market needs.