General review on energy and energy storage requirements. Basicconcepts in energy storage, situation in the world, market and energystorage methods. Electrical energy storage and techniques. Electrical energy storage applications. Batteries (redox, Pb-acid, NiMH, Li-io LiS NaS, Na-ion, solid state batteries etc.), from cell to battery grid scale energy storage. Business models of grid scale energy storage Energy storage legislation and its implementation. Thermal energy storage and applications.