Finnish researchers have developed the world’s first “sand cell” that can preserve green energy for months.
Experts state that this can provide a solution to the problem of using green energy throughout the year.
Using low-density sand, the device is charged with cheap energy from the sun and wind.
Sand maintains heat at around 500 degrees and it is said that it can be used to heat homes in the winter when energy is expensive.
Finland gets most of its gas from Russia. Due to the war in Ukraine, the country started to focus more on green energy.
Russia stopped selling gas and electricity to Finland after Finland’s decision to join NATO.
Finland has a 1300 kilometer border with Russia .
The supply of energy for heating and lighting ahead of the country’s harsh winter is a source of concern for all Finns.
But this system, which was put into operation at a power plant in the west of the country, has the potential to alleviate concerns.
The device uses up to 100 tons of sand. Despite its simple appearance, this system emerges as a cost-effective solution for storing energy to be used when it is most needed.
Investments in renewable energy production are also increasing due to climate change and the rapid rise in the prices of fossil fuels.
Energy from new solar and wind turbines can be immediately incorporated into the grid. But these additional resources have their challenges. The most important issue is continuity. How will you turn on your lights if there is no sun outside and the wind is not blowing?
Also, when you supply renewable energy to power lines, you have to power other energy sources to balance the grid. Because too little or too much energy can cause the system to crash.
The most obvious solution seems to be to build very large-scale batteries to store energy and stabilize demand as the grid becomes more green.
Lithium is currently used in most batteries. These batteries are expensive and have a lot of carbon footprint. In addition, these batteries can remove excess energy to a limited extent.
However, in the town of Kankaanpaa, a group of young engineers completed the first commercial assembly of their sand batteries. They believe they can solve storage problems with this low-cost and low-effective method.
“We want to be able to immediately switch to storage when green energy is plentiful,” says Markku Ylönen, one of the two founders of Polar Night Energy and one of the team that developed the battery.
The sand cell was installed in a section of the Vatajankoski power station. Houses in the region are heated from this power plant.
Low-cost electricity heats the sand up to 500 degrees. The hot air is circulated in the sand with the help of a heat exchanger.
Sand is very conducive to the storage of heat. It causes very little heat loss. The developers of the device say that the sand can stay at 500 degrees for months.
When energy is more expensive, the battery delivers hot air to the district’s water heating system. Hot air heats the water. This water is then pumped into surrounding homes, businesses and even swimming pools.
The sand mixer was developed in a former paper mill in the city of Tampere. The municipality provided funds to entrepreneurs as well as space.
“A power plant that will run for a few hours when the weather is very cold would be prohibitively expensive. But if we have such a solution that provides flexibility of use and heat storage, it will reduce costs,” says energy and climate expert Elina Seppanen.