Within a year, a gigantic world sand battery will be put into operation in Finland. It will be the largest device of its kind in the world.
After the storage of energy in stone, this time it is in Scandinavia that a revolutionary project is in full development. In the small village of Pornainen, in the south of Finland, the construction of a sand battery with an impressive storage capacity of 100 MWh of thermal energy is being prepared. This will allow residents to reduce their dependence on fossil fuels for heating, particularly oil, and reduce their greenhouse gas emissions by around 70%. Further proof that our northern neighbors are ahead in terms of renewable energy.
A promising innovation
This technology is developed by the company Polar Night Energy. Liisa Naskali, COO of the company, expresses her enthusiasm for the project: “ It is exciting to build a large-scale thermal energy storage system, which will also serve as a primary production plant in the Pornainen district heating network “. This alternative solution to conventional energy storage methods will allow the storage of vast quantities of wind and solar energy.
How does a sand battery work? In reality, it’s quite simple, but the principle is effective: resistive heating. The sand is stored in a tower; an electric current passes through it, and therefore heat, from excess energy from solar or wind sources. When current passes through the sand grains (which are not superconductors), it generates heat through friction. Once heated (up to 500°C), the sand is capable of retaining heat for several months. This can then be returned when needed, and can be used to heat water in the district heating network.
A device of the same type already exists in Kankaanpää, a town in the southwest of Finland and the technology has already proven its effectiveness in heating offices or homes. The Polar Night Energy teams will only need to adjust its charging algorithms to develop a similar, albeit much larger, infrastructure in Pornainen.
Materials and ecological impact
So that the use of sand in this technology does not disrupt the ecosystems from which it is taken; which is the case for construction sand, generally extracted from rivers and lakes; Polar Night Energy turned to another solution. The sand used will be crushed soapstone, a by-product of a local company from the manufacture of heat storage fireplaces. By opting for revaluation, the environmental consequences are much more measured.
Polar Night Energy is thinking big because it would like to adopt its solution beyond the country’s borders and for the entire planet to benefit from their advances. A technology that is simple to implement and which could perhaps one day serve as a model to follow in the rest of the world.
Source : Euronews
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