Finland is once again setting a global benchmark in energy storage with the development of a new generation of sand-based thermal batteries, a technology that fundamentally changes the way heat is stored and released for industrial use.
After previous models based on static storage media, such as fixed sand or ramming sand, the new system introduces a completely different principle: the storage material is no longer immobile, but circulates permanently between two tanks, according to the new system. Playtech.
This approach transforms the thermal battery into a dynamic system, capable not only of storing huge amounts of energy as heat, but also of transferring it much faster to industrial processes.
The new technology is already being deployed in a factory in Finland, where it will directly provide industrial steam for technological processes, completely eliminating the need to burn gas or other fossil fuels.
Unlike traditional systems, where sand or other mineral materials are used as static storage mass, the new thermal battery is built on an active circuit.
The system includes two large tanks: one for hot sand and one for cooled sand. In the loading phase, the cold sand is transported through pipes to a heating zone, where it is subjected to electrical resistance and heat exchange, reaching extreme temperatures, currently around 800°C, with a target of 1,000°C in future development stages.
After heating, the sand is directed to the fully insulated thermal storage tank, designed on the principle of an industrial thermos, with insulated walls and an internal vacuum to reduce heat loss.
The models developed by Finnish engineers range from smaller systems with 1 MW of power and 20 MWh of storage to massive industrial installations of 20 MW and 500 MWh.

