The PUSH-IT project: Geothermal energy storage demonstration and advances for different storage technologies and geological settings.

The PUSH-IT project, started in 2023, aims to decarbonize Europe's heating systems, which rely heavily on fossil fuels and constitutes about half of the continent's energy demand. This project focuses on high-temperature (up to 90°C) underground heat storage in geothermal reservoirs to address the seasonal mismatch between heat demand and sustainable heat generation. PUSH-IT develops and showcases 3 UTES technologies at six pilot sites across 4 countries: Aquifer Thermal Energy Storage (ATES) in the Netherlands and Germany, Mine Thermal Energy Storage (MTES) in Germany and the UK, and Borehole Thermal Energy Storage (BTES) in Germany and the Czech Republic. These sites represent diverse geological and demand conditions across Europe. The project encompasses technological advancements in drilling, district heating grids, system monitoring and optimization, and water quality monitoring. It also integrates the technological progress into a frame of enhanced societal engagement, contributions to regulatory frameworks, and economic feasibility, and environmental impact assessments of UTES technologies based on real case data. Geoscientific topics focus on efforts to measure and model heat distribution and perturbations. This includes the application of deep heat exchangers for BTES, insulated parts of ATES wells and BTES boreholes to minimize heating of shallow reservoirs, and extensive temperature sensing in target depths for BTES and ATES systems. Development in drilling and completion technologies is also underway, aimed at optimizing access to storage reservoirs and addressing water quality impact and control at ATES and MTES sites. A significant aspect of PUSH-IT is comparing the effectiveness and viability of ATES, BTES, and MTES across various technological and geological settings. For this contribution, an overview of planned activities, key innovations/technologies will be presented together with some first results from the ATES monitoring well drilling, BTES borehole tests. In summary, the PUSH-IT project represents a comprehensive and innovative approach to enhancing the sustainability and efficiency of heat storage and distribution, potentially setting a new standard in the field of renewable energy and environmental impact reduction for heating and cooling supply. Next to paramount legal, economic and heating system integration topics, the following geosciences topics are being addressed across various sites: Applying 750m deep heat exchangers for BTES systems Using insulated top sections of ATES wells and BTES boreholes to limit the environmental impact (heating) of shallow reservoirs Extensive distributed temperature sensing in target depths of BTES and ATES systems Reservoir performance testing via bespoke tests for BTES and ATES/MTES sites, respectively Expanded diameter gravel well for reducing clogging and increasing flow rates for ATES systems Directional drilling for targeting specific points in abandoned flooded mines for optimal injection/extraction in/from mine galleries Water quality impact and control for ATES and MTES sites Pump monitoring to improve system reliability Acknowledgements: Funded by the European Union under grant agreement 1011096566 (PUSH-IT project). Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or CINEA. Neither the European Union nor CINEA can be held responsible for them.