A closer look at Water Quality
One of the most critical technical challenges in developing sustainable thermal energy storage systems lies beneath the surface—quite literally. One of the enabling technologies the Push-It project is developing is understanding and addressing water quality issues that could impact the long-term viability of these systems. The quality of the water involved plays a vital role in ensuring system performance and longevity.
Our Goal
Rather than simply reacting to issues discovered during pilot site operations, our ambition is to proactively investigate and provide guidance. By doing so, we aim to help future thermal energy storage projects avoid common pitfalls related to water chemistry and microbial activity. We provide recommendations to anticipate and deal with water quality issues for future sites.
Our Research in Action
Our work involves both field monitoring and lab-based experimentation, carried out in collaboration across several research institutions:
- At the Delft and Berlin sites, we contribute through comprehensive water quality monitoring, focusing on both geochemistry and microbiology. We also work with geochemical modelling at those sites.
- In the laboratories of BRGM (the French geological survey), we simulate subsurface conditions to study how microbial communities evolve when exposed to temperature and pressure cycles.
- At GFZ (Geological research center Potsdam), corrosion experiments are underway to better understand how materials interact with varied water chemistries over time.
Tools and Techniques
To carry out this research, we rely on a range of advanced techniques and data sources:
- Water sampling and in-situ measurements to assess chemical and biological parameters
- DNA extraction and sequencing to analyze microbial populations
- Specialized sensors and lab setups that replicate subsurface conditions
Challenges on the Path Ahead
The biggest challenge lies in the complex interplay of physical, chemical, and biological processes in the subsurface environment. Understanding how thermal shifts influence hydrology, geochemistry, and microbiology is a daunting task.
Moreover, microbial sampling and characterization in these contexts are still relatively new frontiers. There’s a pressing need to develop methodologies that can accurately represent subsurface microbial dynamics and integrate them into predictive models.
Where We Stand
Progress is well underway. We are actively engaged in monitoring, modelling, and refining our protocols. A number of experiments are running, and improvements are being made to our monitoring approaches. However, the full picture is still forming. We are currently gathering and analyzing data, and it will take a bit more time before we can confidently share conclusive findings.
PUSH-IT is a project funded by the European Union’s Horizon Europe research and innovation programme under grant agreement No 101096566.
Funded by the European Union. Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union. Neither the European Union nor the granting authority can be held responsible for them.
