An abandoned mine in Finland is set to be transformed into a giant battery to store renewable energy during periods of excess production.
The Pyhäsalmi Mine, roughly 450 kilometres north of Helsinki, is Europe’s deepest zinc and copper mine and holds the potential to store up to 2 MW of energy within its 1,400-metre-deep shafts.
The disused mine will be fitted with a gravity battery, which uses excess energy from renewable sources like solar and wind in order to lift a heavy weight. During periods of low production, the weight is released and used to power a turbine as it drops.
Not if the energy would go to waste. This is a mechanical battery to store surplus power generation from things like wind and solar.
That’s the whole point of grid energy storage. Even if there are losses, it’s acceptable considering that otherwise you would need to burn fossil fuels in a peaker plant to keep the grid balanced. You aren’t supposed to recharge a battery like this with fossil fuels.
It wouldn’t go to waste if we were to use “gravity batteries” that have existed for centuries: hydropower