Geothermal Heat and Abandoned Gas Reservoirs in the Netherlands

Abstract

Sustainable energy in the Netherlands is delivered with success from shallow sub-surface systems, but from depths greater than a few hundreds of metres this is still uncertain. A serious effort to exploit thermal energy from depths where temperatures are sufficiently high for energy companies (>75 oC) was performed at the Vinex (new town extension) location Barendrecht near Rotterdam. A gas field to be abandoned in a few years, could serve as a recipient of the water produced from a selected "hot spot" from the IJsselmonde sandstone at a depth of nearly 2000 m with temperatures of 75-80 oC. A conventional gas reservoir study including interpretation of 3-D seismic data (horizon determination), facies modelling of a complex fluvial-marine environment, petrophysical interpretation of logs of approximately ten wells, hydrochemistry, drilling engineering, reservoir modelling including thermal modelling and geomechanical modelling was performed to delineate the hydraulic, thermal and mechanical behaviour of the reservoir. Probabilistic geological models, generated with state of the art modeling software, were imported in an industry standard black oil simulator. The distance between producer and injector was carefully selected to prevent thermal breakthrough, while maximising the temperature of the produced water. Meanwhile the amount of produced water should fulfil a minimum requirement of 3.2 MW thermal energy with acceptable pressure differences in the wells.