Lake Blåsjö, Norway.
Hydro storage is basically a renewable battery. Lake Blåsjö (“Blue Lake”) in Norway with a capacity of 7.8 terrawatthours (TWh) has become a symbol of Norway’s potential to become a “Blue Battery” for Northern Europe. To put the number in perspective 7.8 TWh would cover the electric consumption of over 750 000 residential homes. To accumulate the same amount of energy with lithium ion batteries it would take over 200 years of full production at Tesla’s planned Gigafactory.