摘要或動機

As part of the European project GEOTHERMICA - ERA NET and in order to assess the capacity of heat storage in Switzerland, the Centre d'Hydrogéologie et de Géothermie de l'Université de Neuchâtel (CHYN) is taking part in the HEATSTORE project, launched in 2018. The latter is expected to lead to commercial heat storage projects in the near future in Geneva and Bern, in fractured aquifers. The evaluation of the geological characteristics of these aquifers is essential to understand the thermal energy transport processes of fractured aquifers. For this, it is necessary to be able to measure the temperature distribution along boreholes. Thus, the study focuses on the evaluation of a distributed temperature system (DTS) and its optical fiber in order to determine its operation, limits and potential for use in geothermal energy. Laboratory and field tests have been carried out that the water temperature deviation measurements, with a scan time of 30 s, are reliable at less than 0.5°C at +/-5 m over 500 m of fiber. For absolute temperature values, however, a bath and a reference probe must be used to recalculate the absolute temperature to within 0.5°C. The acquired data are essential for a broader understanding of the locations of fractured and karstified aquifers at Concise, allowing the system to be used to better understand the potential for water storage at a depth of 45°C at 35 m.