In Finland, in the city of Kankaanpää, at the Vatajankoski power station, the world's first sand battery was installed, which can store green energy and use it after a few months to heat houses.
This technology was developed by a team of Finnish engineers Polar Night Energy, reports BBC.
The accumulator uses 100 tons of low-grade construction sand, which is heated to a temperature of about 500C in a silo-type tank.
Inexpensive electricity heats the sand using resistive heating, which generates hot air that circulates through the sand using a heat exchanger.
Sand is a very efficient medium for storing heat and loses little of it over time. The device can maintain the temperature of the sand for several months.
So, when energy prices are higher, the battery discharges hot air that heats water for the district heating system, which is then supplied to homes, offices and the local swimming pool.
The article noted that Finland received most of its gas from Russia, but after the country's decision to join NATO, the Russian Federation stopped supplying gas and electricity.
"Concerns over sources of heat and light, especially with the long, cold Finnish winter on the horizon are preoccupying politicians and citizens alike," the message reads.
However, a sand battery can solve some problems. After all, adding more renewables to the electricity grid also means adding more other energy sources to balance the grid. Because too much or too little power can cause failure.
Lithium batteries are usually used to store green energy. However, they are expensive, take up a lot of physical space, and can only handle a limited amount of excess energy.
Long-term storage of green energy as heat is also a huge opportunity for industry, where most of the process heat used in food and beverage, textiles or pharmaceuticals comes from burning fossil fuels.
Other research groups, such as the US National Renewable Energy Laboratory, are actively looking at sand as a viable form of battery for sustainable energy. But the Finns are the first with a working, commercial system that works well so far.
As EcoPolitic reported before, in Germany, near Berlin, a 45-meter tower is being built for storage of 56 million liters of hot water.
