Potential of low-temperature aquifer thermal energy storage (LT-ATES) in Germany

Abstract

More than 30% of Germany’s final energy consumption currently results from thermal energy for heating and cooling in the building sector. One possibility to achieve significant greenhouse gas emission savings in space heating and cooling is the application of aquifer thermal energy storage (ATES) systems. Hence, this study maps the spatial technical potential of shallow low-temperature ATES systems in Germany. Important criteria for efficient ATES operation considered in this assessment encompass suitable hydrogeological conditions, such as aquifer productivity and groundwater flow velocity, and balanced space heating and cooling demands. The latter is approximated by the ratio of heating and cooling degree days, which is incorporated as a time-dependent criterion to also evaluate the impact of climate change on the ATES potential. The hydrogeological and climatic criteria are combined within a spatial analysis revealing that, regarding the upcoming decades, about 54% of the investigated German area are very well or well suitable for ATES applications, largely concentrating on three regions: the North German Basin, the Upper Rhine Graben and the South German Molasse Basin. Considering time-dependent climatic conditions, the very well or well suitable areas will increase by 13% for the time period 2071–2100. This is mostly caused by a large relative area increase of the very well suitable regions due to an increasing cooling demand in the future. The sensitivity of the very well and well suitable regions to the criteria weightings is relatively low. Accounting for existing water protection zones shows a reduction of the country-wide share of very well or well suitable areas by around 11%. Nevertheless, the newly created potential map reveals a huge potential for shallow low-temperature ATES systems in Germany.

Indicator of suitability for evaluating the aquifer thermal energy storage using the GIS-based MCDA technique in the Halabja-Khurmal sub-basin

“…The weighting of each criterion is determined based on pairwise one-on-one comparisons between classes of individual criterion through the degree of importance of each class over the others following AHP from the MCDA approach to generate a hierarchical order from one to nine from expert decision-making (Stemmle et al 2022 andSaaty 1980) by using ArcGIS-spatial MCDA-AHP. In this study, the pairwise comparison of the six criteria based on their priority is shown in Table 3.…”

“…However, a suitable aquifer must be carefully chosen for constructing the ATES system. Determination of the suitability of aquifers as thermal energy storage is through assessment of the characterizations of the aquifer (Lee 2013 andStemmle et al 2022), such as climate, geology, physical properties, flow properties, and water quality.…”

“…Multi-spatial data from different sources can be processed by using ArcGIS; as a result, interconnecting MCDA and ArcGIS have a tremendous benefit for creating an ATES suitability map (Chen et al 2010). Analytic hierarchy process (AHP) counts as one of the most common methods of the MCDA used by many authors (Saaty 1977(Saaty , 1980Carver 1991;Saaty and Vargas 1991;Wu 1998;Malczewski 1999aMalczewski ,b, 2000Makropoulos et al 2003;Coyle 2004;Marinoni 2004;Malczewski 2007;Ohta et al 2007;Marinoni et al 2009;Drobne and Lisec 2009;Ferretti 2011;Kara and Doratli 2012;Chabuk, et al 2017;Lu et al 2019b;Alkaradaghi et al 2020;Eddouibi et al 2021;Stemmle et al 2022).…”

Resilience strategies for energy adequacy, between energy storage and conscious behaviours

“…In Europa sono diffusi i sistemi ATES (Aquifer Energy Thermal Storage) (Stemmle et al, 2022), basati sullo stoccaggio e recupero di energia termica dal sottosuolo per il riscaldamento e raffreddamento degli edifici (Bu et al, 2022). Sono sistemi bidirezionale a circuito aperto (Fig.…”