Hiekkasäiliömenetelmä

Hiekkasäiliömenetelmä, known in English as the sand-filled container method or sand battery, is a thermal energy storage technology. It utilizes a large insulated container filled with sand as the storage medium for heat. The primary principle involves heating the sand to high temperatures, often through electricity or other heat sources, and storing this thermal energy within the sand mass.

The heat is typically transferred into and out of the sand using a heat exchanger system. This can involve circulating a heat transfer fluid, such as air or oil, through pipes embedded within the sand. When heat is needed, the stored thermal energy in the sand is transferred to the fluid, which can then be used for heating purposes, such as in buildings or industrial processes.

Sand batteries offer several advantages. Sand is an abundant, inexpensive, and non-toxic material. The technology can store heat at high temperatures, allowing for efficient energy transfer and potentially enabling applications like district heating. Furthermore, sand is non-flammable and stable, contributing to the safety of the system. The insulation of the container is crucial for minimizing heat loss over time, allowing the stored energy to be retained for extended periods. This method is being explored as a way to manage intermittent renewable energy sources by storing excess heat generated during periods of high production for later use.