A new integrated reservoir study based on recently acquired data from the Oranjeoord-01 (ORO-01) exploratory well provides critical new insight into the potential of low-temperature direct use geothermal energy in southwest Netherlands. The study was carried out by Sproule ERCE and Witteveen+Bos, commissioned by Energie Beheer Nederland (EBN) and the Provinces of Zuid-Holland, Noord-Brabant, and Zeeland.
The project focuses on two key goals: improving understanding of the geothermal reservoir and translating that knowledge into realistic, economically viable heat projects.
From an Unknown Reservoir to Reliable Data
Until recently, there was still a limited understanding of the geothermal potential of the Brussels Sand Member. Existing models were based on sparse subsurface data, which led to conservative assumptions about flow rates, permeability and economic viability.
To close this knowledge gap, EBN drilled the SCAN Oranjeoord-01 research well and collected extensive new datasets, including routine core analysis, well logs, geomechanical data, and temperature measurements. These unique data made it possible to directly analyze the reservoir for geothermal use.
Sproule ERCE combined the new core data with seismic information and existing regional datasets to build a fully integrated static subsurface model. This workflow refined existing knowledge and significantly improved understanding of:
- The relationship between permeability and depth
- Facies distribution and its impact on permeability
- Geomechanical behavior of the reservoir under injection-related pressure differentials
As a result, uncertainty around the Brussels Sand reservoir has been substantially reduced.
From Geology to Geothermal Heat Projects
The second focus of the project was turning geological knowledge into practical geothermal outcomes.
Using the new subsurface model, Sproule ERCE calculated:
- Technical flow rates: what the reservoir can physically deliver
- Economic flow rates: what can be produced cost-effectively
This distinction is crucial. Only economically realistic flow rates were used to assess feasibility, ensuring the results are directly relevant for real-world geothermal development.
The study shows that the Brussels Sand is suitable for low-temperature geothermal applications, with production temperatures reaching up to approximately 40 °C and flow rates around 150 m³/hr resulting in single doublet capacities of up to 5 MWth. These temperatures are ideal for direct-use heat projects, such as:
- District heating networks
- Public and commercial buildings
- Greenhouse horticulture
No electricity generation is required, making these systems efficient and locally deployable.
What the Results Mean
The study demonstrates that:
- The permeability of the lower zones in the Brussels Sand Member is relatively lower than previously expected, somewhat reducing the potential geological potential of the reservoir
- The geomechanical properties of the reservoir support higher injection pressures than previously thought, elevating economically feasible flow rates
- Low temperature geothermal energy can support direct heat supply
- Economic feasibility depends on an integrated understanding of the full geothermal system, including subsurface properties, geothermal concept selection, well design and geometry (including deviated wells), production engineering, and the availability of surface heat offtake such as greenhouses and existing or planned heat networks
By coupling detailed geology with economic thresholds and an understanding of evolving heat demand at surface, the SCAN ORO-01 study provides a realistic assessment of where geothermal heat can succeed.
Supporting the Heat Transition
This research plays a key role in the Dutch heat transition. By replacing uncertainty with data-driven insights, the study gives municipalities, geothermal developers and heat network operators a solid foundation on which to explore geothermal solutions.
The results also underline the importance of continued subsurface research as a catalyst for sustainable energy development.
Discover the full results and implications of this SCAN study by reading the complete report on the EBN website:
SCAN Aardwarmte - Implicatiestudie Zeeland, West-Brabant en Zuid-Holland Zuid - EBN
