CE05 - Une énergie durable, propre, sûre et efficace

UPscaling and heat simulations for improving the efficiency of deep GEOthermal energy – UPGEO

UPscaling and heat simulations for improving the efficiency of deep GEOthermal energy - UPGEO

In France, heating networks are largely dependent on fossil fuels (42%), and deep geothermal energy represents less than 5% of the energy mix of heating networks. Deployment of geothermal energy in large cities is limited by a geological risk, difficult to predict. UPGEO will work to develop a predictive numerical tool to perform thermo-hydro-mechanical simulations and assess the performance at a given location in Ile-de-France on its geothermal potential.

Geological risk management, prediction of the efficiency and durability of geothermal doublets in sedimentary environments

Geothermal energy, namely the mobilization of the subsurface heat at very low, low or high temperatures, is one of the methods to achieve the energy transition. There is a real risk that an installation may not reach a geothermal resource with sufficient flow and temperature characteristics to ensure the cost-effectiveness of the project during its life time. These risks consist of t low water flow / thin thickness of reservoir (meter-scale), the risk of interference between geothermal systems in high density of well infrastructures or the risk of early thermal breakthrough. These risks constitute real obstacles for the future development of geothermal energy in Ile-de-France. This projet consists to work on innovation by proposing solutions that optimize and explore the development of new reservoirs. The optimization of the use of deep geothermal energy is a major challenge for the Région Ile-de-France, which has a population of nearly 12 million inhabitants and still growing. This optimization of geothermal production of aquifers requires (1) precise knowledge of the reservoir heterogeneity in terms of sedimentary geometries, porosity/permeability, reservoir connectivity and (2) reliable numerical simulations of flows and temperature evolution in the underground 30 years or even 100 years after production starts. <br /> <br />The main objectives are to successfully perform the upscaling pore- scale laboratory measurements and kilometre-scale sedimentary connectivity of reservoir bodies in order to better predict the resource. The homogenization will give the equations valid at every point of the domain, for both fluid and solid constituents, and in the same time the effective coefficients such as porosities, permeabilities, mechanical deformation (Gassman’tensor and Biot’s coefficient) and effective heat dispersivity. Their determination from the geological data will be the main challenge of this project coupling geological and mathematical concepts.

To sum up, the main methods of UPGEO will be:
- Use well-logs, especially NMR, and cuttings/plugs for µCT scan to characterize facies, microstructure and petrophysic.
- Use of statistics to populate facies and stratigraphic geometries of carbonate and clastic reservoirs.
- Integrate data from outcrop analogues by drone photogrammetry acquisition into 3D reservoir models.
- Propose new concepts of reservoir connectivity, from geostatistical models, to increase reliability of flow simulations.
- Propose new equations for the upscaling (THM equations which include the quasi-static Biot equations) for flow simulation in non-fractured sands/sandstones and fractured carbonate reservoirs.
- Implement simulation codes integrating the upscaling in specific plug-ins on platform such as softwares Eclipse, PumaFlow, OpenGeoSys or DuMuX
- Develop predictive models for flow simulation in carbonate and clastic geothermal sedimentary system.
- Propose an application of the new method to a specific installation to estimate the geological risk for deep geothermal exploration in the Paris Basin, and thus assist in decision-making for a municipality or agglomeration that wants to build a geothermal doublet.
- Provide innovative workflow for simulation applicable to other sedimentary basins.

UPGEO focuses on investigating the fine architecture of the two main geothermal reservoirs (Middle Jurassic limestones and Early Cretaceous sandstones) in the Région Ile-de-France.
The developed geological model will be used to simulate the flow, mechanical and thermal evolution of a geothermal system through time with new mathematical codes for flow simulation including THM and new connectivity indicators in non-fractured sands/sandstones and non-fractured and fractured carbonate reservoirs. It will also provide innovative information to other large cities/regions interested in hydrodynamic simulation of deep geothermal systems in France (e.g. Bordeaux, Lille) or Europe (e.g. Geneva basin, Baviera), or elsewhere in the world. The geological data (logs, facies, petrophysics) will be geolocated in 3D in the Petrel geomodeller. The simulation code integrating the upscaling by THM equations will be integrated as a plug-in on an existing platform such as DuMux (Heidelberg-Stuttgart) in which a thermal part exists but only for thermal flows through rigid porous media, i.e. it does not propose a complete THM solver. The code can be released publically and integrated into other simulation softwares (e.g. non-free TOUGH, Eclipse, PumaFlow, MARTHE softwares). The data acquired in the integrative UPGEO project will allow developing a predictive model of deep geothermal aquifers assisting in decision-making on potentially low-risk areas for future development. Geological model data and simulations can be used for non-commercial purposes by public decision-makers to estimate the geological risk of failure by distinguishing areas with low and high geothermal potential. The model will be evolutive and can be updated with new geological well data (new logs).

Expected findings from this project will contribute to a better understanding of the deep geothermal systems in a large metropole (Paris). It will help us to refine our knowledge on flow simulation including heat evolution of groundwater. UPGEO will make it possible to optimize the implementation of new geothermal doublets and thus develop the use of network heating, which produces only small quantities of greenhouse gas emissions. UPGEO meets the challenges of the energy transition for green growth set by the law of 18 August 2015. The fundamental work performed in the UPGEO project should help to develop new methodologies to significantly reduce the cost of assessment of the geothermal potential around Paris for public authorities (commune, city agglomeration, Grand Paris metropole…), quantifying and reducing risks. Simulations will minimize the potential conflicts of use on the water resource (drink water versus heat or storage). The expertise acquired on sandstone and carbonate aquifers in Ile-de-France can be exported elsewhere in France and internationally (e.g., Bordeaux, Lille, Lyon, Geneva Basin, Baviera, Amsterdam…).

-

Geothermal energy, namely the mobilization of the subsurface heat at very low, low or high temperatures, is one of the methods to achieve the energy transition. The energy-climate strategy plans to increase deep geothermal heat produced in Ile-de-France in 2030 by a 3.5 factor compared to 2015. The current average development rate will not allow this objective to be achieved, it would be necessary to reach a 6 to 10 times higher rate, so the new multiannual renewable geothermal energy programming is being revised downwards in France. Feedback on recent operations in Ile-de-France has raised technical and/or scientific locks to be removed for an efficient and sustainable operation of geothermal doublets, such as the high but unquantified risk of low water flow / thin thickness of reservoir (meter-scale), the risk of interference between geothermal systems in high density of well infrastructures or the risk of early thermal breakthrough. There is a real risk that an installation may not reach a geothermal resource with sufficient flow and temperature characteristics to ensure the cost-effectiveness of the project during its life time. This risk constitutes a real obstacle for the future development of geothermal energy in Ile-de-France. It is clearly established in the energy-climate strategy to work on innovation by proposing solutions that optimize and explore the development of new reservoirs. The optimization of the use of deep geothermal energy is a major challenge for the Région Ile-de-France, which has a population of nearly 12 million inhabitants and still growing. This optimization of geothermal production of aquifers requires (1) precise knowledge of the reservoir heterogeneity in terms of sedimentary geometries, porosity/permeability, reservoir connectivity and (2) reliable numerical simulations of flows and temperature evolution in the underground 30 years or even 100 years after production starts. The main objectives are to successfully perform the upscaling pore-scale laboratory measurements and kilometre-scale sedimentary connectivity of reservoir bodies in order to better predict the resource. The homogenization will give the equations valid at every point of the domain, for both fluid and solid constituents, and in the same time the effective coefficients such as porosities, permeabilities, mechanical deformation (Gassman’tensor and Biot’s coefficient) and effective heat dispersivity. Their determination from the geological data will be the main challenge of this project coupling geological and mathematical concepts.

Project coordinator

Monsieur Benjamin Brigaud (Géosciences Paris-Sud)

The author of this summary is the project coordinator, who is responsible for the content of this summary. The ANR declines any responsibility as for its contents.

Partner

LSCE Laboratoire des Sciences du Climat et de l'Environnement
LMO Laboratoire de mathématiques d'Orsay
ICJ Institut Camille Jordan
G&E GEORESSOURCES & ENVIRONNEMENT
IFPEN Direction Géosciences
GPC-IP GPC INSTRUMENTATION PROCESS / R&D
GEOPS Géosciences Paris-Sud
BRGM BUREAU DE RECHERCHES GEOLOGIQUES ET MINIERES

Help of the ANR 689,391 euros
Beginning and duration of the scientific project: January 2020 - 48 Months

Useful links

Sign up for the latest news:
Subscribe to our newsletter