Guido Slangen, Esmée Boter
Witteveen+Bos, The Netherlands
The municipality of The Hague wants to achieve carbon neutrality by 2030, and seasonal storage of thermal energy is an important challenge in this energy transition. Currently, geothermal projects are under development within the city with the aim of providing domestic heat on a large scale. Additionally, a pipeline network connecting The Hague to residual heat from the Rotterdam harbor area is under construction. These developments provide opportunities for the application of High Temperature Aquifer Thermal Energy Storage (HT-ATES) in The Hague.
A study of the implementation of a HT-ATES system nearby the Combined Cycle Gas Turbine feeding the heating network of the city center of The Hague was carried out. Special attention was given to the possible subsurface risks and mitigation measures. Also, dynamic modelling was carried out in SEAWAT/MODFLOW to test the impact of different well configurations on the storage efficiency.
The subsurface of The Hague contains several suitable aquifers for the implementation of HT-ATES. The most shallow suitable aquifers are situated in the Maassluis formation at depths of around 200 meters below surface. A point of attention is the use of this aquifer for heat-cold storage systems. Sufficient distance is needed between different systems such that none are negatively affected. The current knowledge of the Maassluis formation is that there is a large lateral variation in net thickness and permeability. Therefore, additional test drilling is recommended to assess the applicability of HT-ATES.
The three different well configuration tested are the doublet, clusters of hot and cold wells and the star-shaped configuration. The doublet system has the lowest storage efficiency as due to its limited size there is relatively large amount of heat loss. The other two configuration have a higher storage efficiency and there is only a minor increased storage efficiency of the star-shaped configuration compared to the clustering of hot and cold wells. For a densely populated area with limited available surface area the cluster configuration is therefore preferred because wells are drilled from two surface locations only.
The study concludes that The Hague is a suitable location for the development of HT-ATES. The subsurface risks of HT-ATES can be sufficiently monitored and mitigated. The drilling of test wells is recommended in order to increase the knowledge of the local subsurface and to investigate the applicability of HT-ATES
presentation here