Finnish companies Polar Night Energy and Vatajankoski have built the first commercially operating sand battery which is essentially an insulated silo that is filled with sand.
The sand is used as an energy storing medium, where renewable electricity is converted to heat and then stored. The sand battery has the capacity to store heat at high temperatures for months. This method of storing renewable energy for heating could be a great solution in contrast to some the limitations and expenses of using lithium battery.
The great thing about the construction of the sand battery is that it that the materials can be sourced from anywhere and the quality of sand can be low-grade meaning it doesn’t need to conflict with the building and construction industry where there is a huge demand for high quality sand.
Energy storage is a key issue in the transition to green power, this reliable and effective way of storing excess renewable energy as heat to be used when it is needed most is a fascinating step forwards in this rapidly evolving energy landscape.
(Source: https://polarnightenergy.fi/technology)