Are sand batteries the future of clean energy storage?

The article discusses the emerging role of sand batteries as a promising solution for large-scale, long-duration thermal energy storage, particularly in the context of increasing reliance on intermittent renewable energy sources like wind and solar. Heat accounts for over half of global final energy consumption, especially in industrial processes and building heating, yet efficient thermal storage remains a significant challenge due to heat dissipation and the bulkiness or cost of existing systems. Sand batteries leverage sand’s high specific heat capacity, low thermal conductivity, environmental friendliness, and stability at high temperatures to store thermal energy safely and efficiently without the risks associated with chemical batteries. Sand batteries operate by using surplus renewable electricity to heat air via resistive heaters, which then circulates through insulated steel silos filled with sand, raising its temperature up to around 600–1,000 °C. The sand retains this heat for extended periods with minimal loss, enabling stored thermal energy to be used later for industrial or building heating needs. This approach offers a low-maintenance, scalable,