Objetivo The use of geothermal energy to heat about 40 glasshouses sites from a 15 km distribution network. The reservoir formation to be tapped is situated at a depth of 1,800 m in a karst limestone dated Visean (upper paleozoic). The expected hydrogeological characteristics (85 C and 200 m3/h) will make it possible to supply 87,000 MWh to the network and an energy saving of 2,000 TOE/yr is expected. As the geothermal fluid is highly saline (100 g/l) and in order to maintain the reservoir pressure a reinjection well will have to be drilled. The first tests will conform to the surface network design to optimize the use of geothermal water.A wrong interpretation of seismic recordings done in 1978 led to a bad estimate of the Visean limestones depth.A new seismic profile performed during Hoogstraten well drilling operations (see contract CEE - DG XII EGA 1001 B) indicated that the top limestone should be found between 3,600 and 3,800 m.Information from this borehole should allow geologists to delineate the carbonaceous reservoir with better accuracy.An initial borehole drilled at the beginning of 1980 had to be abandoned at a depth of 700 m because the deviation was too great and one casing fractured. A second borehole was begun a few metres away from the first. At a depth of some 2,000 m many technical problems were encountered owing to the weakness of the borehole walls; after two side trackings a drilling depth of 2,517 m was reached in March 1981, still within the impermeable shale of Westphalian - Namurian covering the Limestone reservoir formation. The borehole walls were of such a nature that a 7" casing had to be sunk to the 2,000 mark (instead of the expected 2,500 m). Further drilling at 6" encountered many difficulties due to resistance of the walls. The decision to abandon drilling was taken in April 1981. Following further drilling (because the Westphalian was proving to be deeper than expected) and after a review of the original seismic studies and new seismic profiles in January 1981 - the depth of the reservoir was re-estimated several times. It is now estimated that the limestone rocks - if there are any - will be found at a depth between 3,600 and 3,800 m, i.e.; at least 2,000 m deeper than originally expected, owing to a considerable increase in the depth of the Westphalian-Namurian formation (Carboniferous shales). Since, under such drilling conditions, it was impossible within reasonable economic limits to carry on drilling to a sufficient depth to tap the reservoir, the well was stopped. Programa(s) ENG-ENALT 1C - Programme (EEC) of financial support for projects to exploit alternative energy sources, 1979-1984 Tema(s) 2.2 - HEATING Convocatoria de propuestas Data not available Régimen de financiación DEM - Demonstration contracts Coordinador GEWESTELIJKE ONTWIKKELINGSMAATSCHAPPIJ ANTWERPEN Aportación de la UE Sin datos Dirección DESGUINLEI 102 BUS 13 2018 Antwerpen Bélgica Ver en el mapa Coste total Sin datos
