The prevailing view in the scientific community is that large amounts of carbon dioxide (CO₂) from the atmosphere and highly radioactive waste must be disposed of safely. In that regard, studies on natural processes that extend over thousands of years help to assess the long-term behaviour of deep geological repositories. From a purely scientific point of view, CO₂ storage and final disposal of highly radioactive waste are feasible.

This article presents the map and dataset of critical raw materials (CRM) deposits in Europe produced within the GSEU (Geological Service for Europe) project. The map displays over 800 deposits in 33 countries. The article describes the methodology for compiling and harmonizing data, as well as a global assessment of CRM potential in Europe. It also discusses barriers of compiling and harmonizing CRM data at continental scale, and the limitations of the map and its dataset.

The division on Energy, Resources, and the Environment (ERE) of the European Geosciences Union (EGU) follows an interdisciplinary approach. This volume of Advances in Geosciences presents papers covering key themes from recent developments, beside others, in geothermal systems, critical raw materials, carbon cycle dynamics and renewable energy integration, emphasizing the role of interdisciplinary research in overcoming technical, economic, and societal challenges.

To accelerate the heat transition in Germany the ArtemIS project focuses on the geothermal assessment of medium-depth reservoirs on a region-wide basis, covering all geological play types based on structural and numerical reservoir models. The results are incorporated into the GeotIS internet platform to create interactive “heat transition profiles”, which provide all necessary technical and subsurface data for each play type to perform preliminary geothermal assessment studies.

The world needs a shift from fossil fuels, and geothermal energy is a clean energy source. Aquifer thermal energy storage (ATES) system is an example of a shallow geothermal resource. This study estimates the porosity of the Permo-Triassic Sherwood Sandstone Group for ATES system using borehole nuclear magnetic resonance (BNMR) and Petrophysical models. This study confirms storage capacities in the lower Sherwood Sandstone Group of Northern Ireland that make it suitable for ATES systems.

This study explores how rock salt reacts to hydrogen, aiming to support safe underground storage of renewable energy. Lab tests on samples from a potential salt cavern-type site in Spain showed that hydrogen caused no major changes to the rock. Minor effects were limited and did not impact overall stability. These findings help confirm that storing hydrogen in salt formations is a safe and reliable option for future energy systems.

The effect of spatial variability on uranium diffusion in Opalinus Clay over a million years was assessed by 2D reactive transport simulations. Different rock types and porosity impacted results, with variability's influence growing with longer correlation lengths of geostatistical simulations (up to 12.9 %). This highlights that 1D models may underestimate uncertainty in long-term radionuclide transport at repository sites, and spatial variability must be considered.

In natural hydrogen exploration, locating deep gas seepage is often done by measuring soil gas content. For that purpose, we developed a long-term hydrogen concentration monitoring instrument named MONHyTOR. Our laboratory test demonstrates its accuracy, and field data indicate that hydrogen circulation in the soil depend on soil type, water circulation in the soil, air pressure, and air temperature. MONHyTOR can prove to be a promising tool in the natural hydrogen exploration scene.

We introduce a novel coupling of GOLEM, a thermal-hydraulic-mechanical simulator, with the PHREEQC geochemical solver. The code is validated via benchmarks against reference 1D models and its functionalities demonstrated on a 2D geochemical heterogeneous domain. This open-source  software enables the simulation of complex subsurface processes for the development of geothermal resources.

On 7–9 January 2005 Storm Erwin passed across northern Europe, causing damage from Ireland to Russia, including power outages. Southern Sweden had the worst impacts with two nuclear stations shut-down and widespread destruction of transmission lines. For offshore wind energy in the North Sea, the storm was important to understand extreme environmental conditions for turbine operation. This work presents an analysis of North Sea tide gauge and wave data to assess extreme wave and surge levels.

The safe disposal of nuclear waste requires consideration of future developments in nature on the repository, like for instance glacifications. We show an approach by using a sophisticated database for a systematic consideration of such developments and their possible interactions.

To make better use of underground heat storage, we need to understand how water flows through deep rock layers. Normally, this is tested after drilling is finished, but we tried doing it during an earlier stage to save time and effort. At a site in Berlin, we tested a new way to measure how water moves through rock while the borehole was still being developed. The method worked well and gives quicker, reliable insights into underground conditions.

Waiwera in New Zealand is a small coastal village with a geothermal reservoir underneath. Hydrogeological models support water management by providing insights into sustainable extraction from the system. It is artesian and the geothermal water is of meteoric origin percolating down to sufficient depth getting heated. It rises through a fault zone into the shallow and leaky aquifer. Most recently the springs have restarted discharging geothermal water on the beach.

We mapped pore networks in carbonate scanning-electron-microscope (SEM) images to aid safe CO₂ storage and radioactive-waste isolation. An open 29 000 × 23 000-pixel mosaic was split into 100 fully hand-labelled tiles. Eight classic computer-vision pipelines were benchmarked: Watershed gave the best recall–precision balance, and a simple Hybrid-Voting of three filters halved false alarms. The data, masks and code offer an immediate reference set for training and testing future 3-D deep-learning models.

In cities, large thermal plumes often limit groundwater-based heating and cooling. Unidirectional ATES reverses the well arrangement so heat and cold are transported by natural groundwater flow and reused seasonally. At Graz South Hospital, modeling shows efficient energy recovery, strongly reduced off-site impacts, and high potential for climate-friendly energy supply in space-constrained urban areas.

We studied how the chemical composition of water in rocks affects the movement of uranium, which is important for the safety of nuclear waste disposal sites. Using computer models, we found that water chemistry inside the host rock for the waste is more decisive for the transport of uranium than groundwater chemistry in adjacent rocks. These findings help improve site selection for a disposal site by indicating which conditions are suitable and less suitable to safely isolate radioactive waste.

Climate change has negative effects on water resources. It creates conflicts among stakeholders at Lake Velence. This region is undegoing rapid urbanization and economic expansion, while includes significant wetland areas, some are under protection. It has high density of solar panel installations. Our research proposes a water transfer system, using renewable energy potential to reduce water shortages. Besides the recipient area, we also consider the protection of ecosystems at the donor area.