In the heart of Poland, a groundbreaking concept is taking shape, one that could revolutionize how we store and utilize renewable energy. Kamil Szewerda, a researcher at the KOMAG Institute of Mining Technology in Gliwice, is leading a pioneering effort to transform abandoned underground mine workings into high-temperature sand thermal energy storage systems. This innovative approach, detailed in a recent study published in the journal Applied Sciences, could address some of the most pressing challenges in the energy sector, from balancing the grid to reducing greenhouse gas emissions.
The idea is deceptively simple: use the vast, empty spaces left behind by decommissioned mines to store thermal energy generated by solar panels and wind turbines. During the summer, when renewable energy sources often produce more power than the grid can handle, this excess energy would be used to heat sand stored in the underground excavations. Come winter, when energy demand spikes and renewable sources are less productive, the stored heat could be released to warm homes, public buildings, and even industrial processes.
“Post-industrial areas, often located near city centers, are ideal for large-scale heat storage facilities,” Szewerda explains. “By repurposing these abandoned mines, we can create a sustainable solution that not only reduces heating costs but also decreases greenhouse gas emissions and helps balance the power grid.”
The concept is not just theoretical. Szewerda and his team have developed three variants of the thermal energy storage system, ranging from small-scale demonstrators to large facilities capable of meeting the needs of entire cities or counties. The key to the system’s efficiency lies in the properties of sand, which can store heat at high temperatures for extended periods.
The potential commercial impacts of this research are significant. As Europe pushes towards decarbonization and the goals of the Green Deal, the need for effective energy storage solutions is becoming increasingly urgent. Traditional energy storage methods, such as batteries, have their limitations, particularly in terms of scale and cost. Sand-based thermal energy storage, on the other hand, offers a scalable, cost-effective alternative that can be integrated into existing infrastructure.
Moreover, the use of underground mine workings presents a unique opportunity to repurpose industrial heritage sites, creating new economic opportunities for regions that have historically relied on mining. “This approach not only addresses energy storage challenges but also contributes to the revitalization of post-industrial areas,” Szewerda notes.
The research builds on successful pilot projects, such as the world’s first commercial “sand battery” in Finland, which has demonstrated the feasibility of using sand as a heat storage medium. However, Szewerda’s concept takes this a step further by proposing the use of underground mine workings, which offer natural insulation and the potential for large-scale storage.
As the energy sector continues to evolve, the need for innovative storage solutions will only grow. Szewerda’s work, published in Applied Sciences, titled “Concept of Adapting the Liquidated Underground Mine Workings into High-Temperature Sand Thermal Energy Storage,” offers a compelling vision for the future of energy storage. By repurposing abandoned mines and leveraging the unique properties of sand, this research could pave the way for a more sustainable, efficient, and resilient energy system. The potential benefits are vast, from reducing carbon emissions to creating new economic opportunities in post-industrial regions. As the world seeks to transition to a greener future, concepts like this one will be crucial in shaping the energy landscape of tomorrow.
