Can builder's sand save energy?

Around 100 tonnes of builder's sand, piled high inside a dull grey silo. These rough and ready grains may well represent a simple, cost-effective way of storing power for when it's needed most. Because of climate change and now thanks to the rapidly rising price of fossil fuels, there's a surge of investment in new renewable energy production.

Can a sand battery save energy?

"A sand battery stores five to 10 times less energy [per unit volume] than traditional chemical batteries," says Dan Gladwin from the department of electronic and electrical engineering at the University of Sheffield in the UK. The Polar Night Energy team acknowledges this but argues that a sand battery is a far more cost-effective solution.

Could sand be a viable battery for green power?

Other research groups, such as the US National Renewable Energy Laboratory are actively looking at sand as a viable form of battery for green power. But the Finns are the first with a working, commercial system, that so far is performing well, according to the man who's invested in the system.

Can a sand battery solve a storage problem?

But in the town of Kankaanpää, a team of young Finnish engineers have completed the first commercial installation of a battery made from sand that they believe can solve the storage problem in a low-cost, low impact way.

How does sand become a battery?

The sand becomes a battery after it is heated up to 600C using electricity generated by wind turbines and solar panels in Finland, brought by Vatajankoski, the owners of the power plant. The renewable energy powers a resistance heater which heats up the air inside the sand.

How does a solar sand battery work?

The renewable energy powers a resistance heater which heats up the air inside the sand. Inside the battery, this hot air is circulated by a fan around the sand through heat exchange pipes. Thick insulation surrounds the sand, keeping the temperature inside the battery at 600C (1,112F), even when it is freezing outside.