text: why sodium-sulphur cells can be used to reduce the wastage of electricity? sodium-sulphur cells are rechargeable and are used in power stations to reduce the wastage of electricity generated this type of battery exhibits a high energy density, high efficiency of charge/discharge (89—92%), long cycle life, and is made from inexpensive, non-toxic materials. however, the operating temperature of 300 to 350 °c and the highly corrosive nature of sodium make it suitable only for large-scale non-mobile applications. a suggested application is grid energy storage in the electric grid. a 6mw-hr system has been installed at tsunashima japan.