The world's first sand battery
Renewable energy -
When it comes to renewable energy, we have made significant progress over the last two decades.
There are many countries that have renewable energy contributing to more than 20% of their total energy supply.
Key challenges - One of the biggest challenges is how we can provide a year-round, steady supply of energy from renewable sources.
Hope for the future -
There are four young engineers in Finland, however, who believe they may have found the solution. Enter the world’s first commercial-scale sand battery.
Introducing the sand battery -
Within the Vatajankoski power plant (about a three-hours' drive northwest of Helsinki) stands a 23 ft (7 m) steel container.
How it works -
The sand becomes a battery when it is heated to 600°C, using electricity generated by wind turbines and solar panels in Finland.
How it works -
The battery stores around 8 MWh of thermal energy when it's full, and it is surrounded by thick insulation, which keeps the sand hot even when it is freezing outside.
Discharging heat -
When the demand for heat rises, the battery discharges around 200 kW of power through its heat exchange pipes.
That is enough to heat and provide hot water for around 100 homes and a public swimming pool, supplementing power from the grid.
Charging the battery -
The battery is then charged overnight when the cost of electricity is lower.
Sustainable sand -
This means that it does not contribute to the global shortage of high-quality river sand, which is used in very large quantities for construction.
Long-term solution -
Sand is very effective at retaining heat over a long period of time, and it can store power for months on end.
Lithium-ion comparison -
In terms of comparison with lithium-ion batteries (as the most commonly used alternative), the sand battery has a number of advantages.
CO2 emissions -
Then there’s the environmental impact to consider: lithium is much worse than sand in terms of CO2 emissions.
Electricity generation -
They also need to consider how they will use the battery to generate significant amounts of electricity in addition to heat.
Getting close -
According to engineer and team member Tommi Eronen, they will have a working system to do that in the next two years.
Global plans -
Currently the sand battery is a uniquely Nordic solution to renewable energy storage. In theory, however, it could have applications all over the world.
The mission -
According to Eronen, the aim is to become "a truly global company, constructing sand batteries all over the world" by 2023.